Search results
Search for "carbon dioxide" in Full Text gives 127 result(s) in Beilstein Journal of Organic Chemistry.
Direct electrochemical generation of organic carbonates by dehydrogenative coupling
- Tile Gieshoff,
- Vinh Trieu,
- Jan Heijl and
- Siegfried R. Waldvogel
Beilstein J. Org. Chem. 2018, 14, 1578–1582, doi:10.3762/bjoc.14.135
- (Figure 1) [4][5][6]. However, both alternatives do not compete with the phosgene approach, since catalyst, excessive amounts of reagents, or harsh reaction conditions are necessary and provide rather low yields. Contemporary research also focuses on the incorporation of carbon dioxide by catalytic
- . Therefore, tetrabutylammonium methyl carbonate was employed. The solubility in acetonitrile is attributed to the tetrabutylammonium counterion. Its preparation is very simple by direct treatment of carbon dioxide with the methoxide alkylammonium salt (Scheme 1) [32]. Since this carbonate source is blocked
- installation of oxygen functionalization onto aromatic substrates. Current non-phosgene approaches to organic carbonates. Influence of the electrode distance; a 1H NMR yield; bisolated yield. Preparation of tetrabutylammonium methyl carbonate by direct carbon dioxide incorporation. Direct generation of mesityl
Graphical Abstract
Figure 1: Current non-phosgene approaches to organic carbonates.
Scheme 1: Preparation of tetrabutylammonium methyl carbonate by direct carbon dioxide incorporation.
Scheme 2: Direct generation of mesityl methyl carbonate by dehydrogenative functionalization.
Figure 2: Influence of the electrode distance; a 1H NMR yield; bisolated yield.
[3 + 2]-Cycloaddition reaction of sydnones with alkynes
- Veronika Hladíková,
- Jiří Váňa and
- Jiří Hanusek
Beilstein J. Org. Chem. 2018, 14, 1317–1348, doi:10.3762/bjoc.14.113
- supercritical carbon dioxide [41] in which 65 and 83% yields of dimethyl (or diethyl) 1-phenylpyrazole-3,4-dicarboxylates were achieved. Only in two cases involving 3-(2,4,6-trisubstituted phenyl)-4-iodosydnones (R1: 2-Br-4,6-diMe-Ph, 2,4-diBr-6-Me-Ph; R2: I) and DMAD (or its diethyl analogue) did the
Graphical Abstract
Scheme 1: Thermal reaction of sydnones with symmetrical alkynes.
Scheme 2: Reaction of sydnones with strained cycloalkynes.
Scheme 3: Reaction of sydnones with didehydrobenzenes.
Scheme 4: Formation of isomeric pyrazole dicarboxylates.
Scheme 5: Mechanism of thermal cycloaddition between sydnones and alkynes.
Scheme 6: Mechanism of photochemical reaction of sydnones with symmetrical alkynes.
Scheme 7: HOMO–LUMO diagram for thermal [3 + 2]-cycloaddition of sydnones with alkynes.
Scheme 8: Synthetic strategy leading to 1,2-disubstituted pyrazoles.
Scheme 9: Unsuccessful reaction with phenylpropiolic acid.
Scheme 10: Synthetic strategy leading to 1,4,5-trisubstituted pyrazoles.
Scheme 11: Reaction of sydnones carrying in position 4- six-membered 2-N-heterocyclic ring.
Scheme 12: Strain-promoted sydnone alkyne cycloaddition (SPSAC).
Scheme 13: Synthesis of a key intermediate of niraparib.
Scheme 14: Reaction of sydnones with 1,3-/1,4-benzdiyne equivalents.
Scheme 15: Reaction of sydnones with heterocyclic strained cycloalkynes.
Scheme 16: Mono-copper catalyzed cycloaddition reaction.
Scheme 17: Di-copper catalyzed cycloaddition reaction.
One hundred years of benzotropone chemistry
- Arif Dastan,
- Haydar Kilic and
- Nurullah Saracoglu
Beilstein J. Org. Chem. 2018, 14, 1120–1180, doi:10.3762/bjoc.14.98
Graphical Abstract
Scheme 1: Tropone (1), tropolone (2) and their resonance structures.
Figure 1: Natural products containing a tropone nucleus.
Figure 2: Possible isomers 11–13 of benzotropone.
Scheme 2: Synthesis of benzotropones 11 and 12.
Scheme 3: Oxidation products of benzotropylium fluoroborate (16).
Scheme 4: Oxidation of 7-bromo-5H-benzo[7]annulene (22).
Scheme 5: Synthesis of 4,5-benzotropone (11) using o-phthalaldehyde (27).
Scheme 6: Synthesis of 4,5-benzotropone (11) starting from oxobenzonorbornadiene 31.
Scheme 7: Acid-catalyzed cleavage of oxo-bridge of 34.
Scheme 8: Synthesis of 4,5-benzotropone (11) from o-xylylene dibromide (38).
Scheme 9: Synthesis of 4,5-benzotropone (11) via the carbene adduct 41.
Scheme 10: Heck coupling strategy for the synthesis of 11.
Scheme 11: Synthesis of benzofulvalenes via carbonyl group of 4,5-benzotropone (11).
Figure 3: Some cycloheptatrienylium cations.
Scheme 12: Synthesis of condensation product 63 and its subsequent oxidative cyclization products.
Figure 4: A novel series of benzo[7]annulenes prepared from 4,5-benzotropone (11).
Scheme 13: Preparation of substituted benzo[7]annulene 72 using the Mukaiyama-Michael reaction.
Figure 5: Possible benzo[7]annulenylidenes 73–75.
Scheme 14: Thermal and photochemical decomposition of 7-diazo-7H-benzo[7]annulene (76) and the trapping of int...
Scheme 15: Synthesis of benzoheptafulvalene 86.
Scheme 16: Synthesis of 7-(diphenylmethylene)-7H-benzo[7]annulene (89).
Scheme 17: Reaction of 4,5-benzotropone (11) with dimethyl diazomethane.
Scheme 18: Synthesis of dihydrobenzomethoxyazocine 103.
Scheme 19: Synthesis and reducibility of benzo-homo-2-methoxyazocines.
Scheme 20: Synthesis of 4,5-benzohomotropones 104 and 115 from 4,5-benzotropones 11 and 113.
Scheme 21: A catalytic deuterogenation of 4,5-benzotropone (11) and synthesis of 5-monosubstituted benzo[7]ann...
Scheme 22: Synthesis of methyl benzo[7]annulenes 131 and 132.
Scheme 23: Ambident reactivity of halobenzo[7]annulenylium cations 133a/b.
Scheme 24: Preparation of benzo[7]annulenylidene–iron complexes 147.
Scheme 25: Synthesis of 1-ethynylbenzotropone (150) and the etheric compound 152 from 4,5-benzotropone (11) wi...
Scheme 26: Thermal decomposition of 4,5-benzotropone (11).
Scheme 27: Reaction of 4,5-benzotropone (11) with 1,2-ethanediol and 1,2-ethanedithiol.
Scheme 28: Conversions of 1-benzosuberone (162) to 2,3-benzotropone (12).
Scheme 29: Synthesis strategies for 2,3-bezotropone (12) using 1-benzosuberones.
Scheme 30: Oxidation-based synthesis of 2,3-benzotropone (12) via 1-benzosuberone (162).
Scheme 31: Synthesis of 2,3-benzotropone (12) from α-tetralone (171) via ring-expansion.
Scheme 32: Preparation of 2,3-benzotropone (12) by using of benzotropolone 174.
Figure 6: Benzoheptafulvenes as condensation products of 2,3-benzotropone (12).
Scheme 33: Conversion of 2,3-benzotropone (12) to tosylhydrazone salt 182 and gem-dichloride 187.
Figure 7: Benzohomoazocines 191–193 and benzoazocines 194–197.
Scheme 34: From 2,3-benzotropone (12) to carbonium ions 198–201.
Scheme 35: Cycloaddition reactions of 2,3-benzotropone (12).
Scheme 36: Reaction of 2,3-benzotropone (12) with various reagents and compounds.
Figure 8: 3,4-Benzotropone (13) and its resonance structure.
Scheme 37: Synthesis of 6,7-benzobicyclo[3.2.0]hepta-3,6-dien-2-one (230).
Figure 9: Photolysis and thermolysis products of 230.
Figure 10: Benzotropolones and their tautomeric structures.
Scheme 38: Synthesis strategies of 4,5-benzotropolone (238).
Scheme 39: Synthesis protocol for 2-hydroxy-4,5-benzotropone (238) using oxazole-benzo[7]annulene 247.
Figure 11: Some quinoxaline and pyrazine derivatives 254–256 prepared from 4,5-benzotropolone (238).
Scheme 40: Nitration product of 4,5-benzotropolone (238) and its isomerization to 1-nitro-naphthoic acid (259)....
Scheme 41: Synthesis protocol for 6-hydroxy-2,3-benzotropone (239) from benzosuberone (162).
Scheme 42: Various reactions via 6-hydroxy-2,3-benzotropone (239).
Scheme 43: Photoreaction of 6-hydroxy-2,3-benzotropone (239).
Scheme 44: Synthesis of 7-hydroxy-2,3-benzotropone (241) from benzosuberone (162).
Scheme 45: Synthesis strategy for 7-hydroxy-2,3-benzotropone (241) from ketone 276.
Scheme 46: Synthesis of 7-hydroxy-2,3-benzotropone (241) from β-naphthoquinone (280).
Scheme 47: Synthesis of 7-hydroxy-2,3-benzotropone (241) from bicyclic endoperoxide 213.
Scheme 48: Synthesis of 7-hydroxy-2,3-benzotropone (241) by ring-closing metathesis.
Figure 12: Various monosubstitution products 289–291 of 7-hydroxy-2,3-benzotropone (241).
Scheme 49: Reaction of 7-hydroxy-2,3-benzotropone (241) with various reagents.
Scheme 50: Synthesis of 4-hydroxy-2,3-benzotropones 174 and 304 from diketones 300/301.
Scheme 51: Catalytic hydrogenation of diketones 300 and 174.
Scheme 52: Synthesis of halo-benzotropones from alkoxy-naphthalenes 306, 307 and 310.
Figure 13: Unexpected byproducts 313–315 during synthesis of chlorobenzotropone 309.
Figure 14: Some halobenzotropones and their cycloadducts.
Scheme 53: Multisep synthesis of 2-chlorobenzotropone 309.
Scheme 54: A multistep synthesis of 2-bromo-benzotropone 26.
Scheme 55: A multistep synthesis of bromo-2,3-benzotropones 311 and 316.
Scheme 56: Oxidation reactions of 8-bromo-5H-benzo[7]annulene (329) with some oxidants.
Scheme 57: Synthesis of 2-bromo-4,5-benzotropone (26).
Scheme 58: Synthesis of 6-chloro-2,3-benzotropone (335) using LiCl and proposed intermediate 336.
Scheme 59: Reaction of 7-bromo-2,3-benzotropone (316) with methylamine.
Scheme 60: Reactions of bromo-2,3-benzotropones 26 and 311 with dimethylamine.
Scheme 61: Reactions of bromobenzotropones 311 and 26 with NaOMe.
Scheme 62: Reactions of bromobenzotropones 26 and 312 with t-BuOK in the presence of DPIBF.
Scheme 63: Cobalt-catalyzed reductive cross-couplings of 7-bromo-2,3-benzotropone (316) with cyclic α-bromo en...
Figure 15: Cycloadduct 357 and its di-π-methane rearrangement product 358.
Scheme 64: Catalytic hydrogenation of 2-chloro-4,5-benzotropone (311).
Scheme 65: Synthesis of dibromo-benzotropones from benzotropones.
Scheme 66: Bromination/dehydrobromination of benzosuberone (162).
Scheme 67: Some transformations of isomeric dibromo-benzotropones 261A/B.
Scheme 68: Transformations of benzotropolone 239B to halobenzotropolones 369–371.
Figure 16: Bromobenzotropolones 372–376 and 290 prepared via bromination/dehydrobromination strategy.
Scheme 69: Synthesis of some halobenzotropolones 289, 377 and 378.
Figure 17: Bromo-chloro-derivatives 379–381 prepared via chlorination.
Scheme 70: Synthesis of 7-iodo-3,4-benzotropolone (382).
Scheme 71: Hydrogenation of bromobenzotropolones 369 and 370.
Scheme 72: Debromination reactions of mono- and dibromides 290 and 375.
Figure 18: Nitratation and oxidation products of some halobenzotropolenes.
Scheme 73: Azo-coupling reactions of some halobenzotropolones 294, 375 and 378.
Figure 19: Four possible isomers of dibenzotropones 396–399.
Figure 20: Resonance structures of tribenzotropone (400).
Scheme 74: Two synthetic pathways for tribenzotropone (400).
Scheme 75: Synthesis of tribenzotropone (400) from dibenzotropone 399.
Scheme 76: Synthesis of tribenzotropone (400) from 9,10-phenanthraquinone (406).
Scheme 77: Synthesis of tribenzotropone (400) from trifluoromethyl-substituted arene 411.
Figure 21: Dibenzosuberone (414).
Figure 22: Reduction products 415 and 416 of tribenzotropone (400).
Figure 23: Structures of tribenzotropone dimethyl ketal 417 and 4-phenylfluorenone (412) and proposed intermed...
Figure 24: Structures of benzylidene- and methylene-9H-tribenzo[a,c,e][7]annulenes 419 and 420 and chiral phos...
Figure 25: Structures of tetracyclic alcohol 422, p-quinone methide 423 and cation 424.
Figure 26: Structures of host molecules 425–427.
Scheme 78: Synthesis of non-helical overcrowded derivatives syn/anti-431.
Figure 27: Hexabenzooctalene 432.
Figure 28: Structures of possible eight isomers 433–440 of naphthotropone.
Scheme 79: Synthesis of naphthotropone 437 starting from 1-phenylcycloheptene (441).
Scheme 80: Synthesis of 10-hydroxy-11H-cyclohepta[a]naphthalen-11-one (448) from diester 445.
Scheme 81: Synthesis of naphthotropone 433.
Scheme 82: Synthesis of naphthotropones 433 and 434 via cycloaddition reaction.
Scheme 83: Synthesis of naphthotropone 434 starting from 452.
Figure 29: Structures of tricarbonyl(tropone)irons 458, and possible cycloadducts 459.
Scheme 84: Synthesis of naphthotropone 436.
Scheme 85: Synthesis of precursor 465 for naphthotropone 435.
Scheme 86: Generation of naphthotropone 435 from 465.
Figure 30: Structures of tropylium cations 469 and 470.
Figure 31: Structures of tropylium ions 471+.BF4−, 472+.BF4−, and 473+.BF4−.
Scheme 87: Synthesis of tropylium ions 471+.BF4− and 479+.ClO4−.
Scheme 88: Synthesis of 1- and 2-methylanthracene (481 and 482) via carbene–carbene rearrangement.
Figure 32: Trapping products 488–490.
Scheme 89: Generation and chemistry of a naphthoannelated cycloheptatrienylidene-cycloheptatetraene intermedia...
Scheme 90: Proposed intermediates and reaction pathways for adduct 498.
Scheme 91: Exited-state intramolecular proton transfer of 505.
Figure 33: Benzoditropones 506 and 507.
Scheme 92: Synthesis of benzoditropone 506e.
Scheme 93: Synthetic approaches for dibenzotropone 507 via tropone (1).
Scheme 94: Formation mechanisms of benzoditropone 507 and 516 via 515.
Scheme 95: Synthesis of benzoditropones 525 and 526 from pyromellitic dianhydride (527).
Figure 34: Possible three benzocyclobutatropones 534–536.
Scheme 96: Synthesis of benzocyclobutatropones 534 and 539.
Scheme 97: Synthesis attempts for benzocyclobutatropone 545.
Scheme 98: Generation and trapping of symmetric benzocyclobutatropone 536.
Scheme 99: Synthesis of chloro-benzocyclobutatropone 552 and proposed mechanism of fluorenone derivatives.
Scheme 100: Synthesis of tropolone analogue 559.
Scheme 101: Synthesis of tropolones 561 and 562.
Figure 35: o/p-Tropoquinone rings (563 and 564) and benzotropoquinones (565–567).
Scheme 102: Synthesis of benzotropoquinone 566.
Scheme 103: Synthesis of benzotropoquinone 567 via a Diels–Alder reaction.
Figure 36: Products 575–577 through 1,2,3-benzotropoquinone hydrate 569.
Scheme 104: Structures 578–582 prepared from tropoquinone 567.
Figure 37: Two possible structures 583 and 584 for dibenzotropoquinone, and precursor compound 585 for 583.
Scheme 105: Synthesis of saddle-shaped ketone 592 using dibenzotropoquinone 584.
Polysubstituted ferrocenes as tunable redox mediators
- Sven D. Waniek,
- Jan Klett,
- Christoph Förster and
- Katja Heinze
Beilstein J. Org. Chem. 2018, 14, 1004–1015, doi:10.3762/bjoc.14.86
- application as redox mediator (Scheme 2) [55][56]. Ferrocenyl esters 1–4 are synthetically accessible via the acids of 1 [45][46], 2 [57], 3 and 4 [54] in a direct selective metalation of ferrocene [54][57][58][59][60], quenching with carbon dioxide, followed by esterification [45][46][47][48][54]. The 1,1
Graphical Abstract
Scheme 1: Selected transformations with ferrocene/ferrocenium as SET reagents (a) [27], catalyzed (b,c) [29-31] and medi...
Scheme 2: Methyl esters of ferrocene carboxylic acids 1 [45,46], 2 [47-49], 2a [50], 2b [51,52], 3, 4 [54] and pseudo octahedral high-spin...
Figure 1: Normalized cyclic voltammograms for anodic sweeps of 1–4 in CH2Cl2/[n-Bu4N][B(C6F5)4] (scan rate 10...
Figure 2: Electrochemical potentials E1/2 (vs FcH/FcH+) of esters 1–4 versus sum of Hammett values ∑σp/m with...
Figure 3: a) Partial ATR IR spectra (transmission normalized, C=O stretching vibration region) of solids 1–4....
Figure 4: IR spectroelectrochemical oxidation of 3 to 3+ in CH2Cl2/[n-Bu4N][B(C6F5)4] (C=O stretching vibrati...
Figure 5: a) Normalized UV–vis spectra of 1–4 in CH2Cl2. b) Normalized UV–vis absorptions of 1+–4+ in CH2Cl2/[...
Figure 6: Absorption energy E of ferrocene bands of 1–4 (a) and energies of the low energy absorption maxima ...
Figure 7: UV–vis spectroelectrochemical oxidation of 3 in CH2Cl2/[n-Bu4N][B(C6F5)4] (0–1.1 V vs Ag pseudo ref...
Figure 8: 1H NMR oxidation titration of 3 in CD2Cl2 with [N(2,4-C6H3Br2)3]+ as oxidant. a[N(2,4-C6H3Br2)3]. b...
Crystal structure of the inclusion complex of cholesterol in β-cyclodextrin and molecular dynamics studies
- Elias Christoforides,
- Andreas Papaioannou and
- Kostas Bethanis
Beilstein J. Org. Chem. 2018, 14, 838–848, doi:10.3762/bjoc.14.69
- organic solvents, supercritical carbon dioxide extraction or cholesterol degradation by cholesterol oxidases. But these methods are not selective as other components are also removed and they require expensive equipment and high operational cost [21]. In the past, many studies have been published on the
Graphical Abstract
Figure 1: Schematic representation of (a) the cholesterol molecule; (b) the β-cyclodextrin molecule.
Figure 2: (a) Crystal structure of the inclusion compound of cholesterol in β-CD dimer. Water molecules are o...
Figure 3: RMSD over time for all CHL (green) and β-CD (blue) atoms (a) at 300 K and (b) at 340 K.
Figure 4: Representative snapshots of the CHL/β-CD inclusion complex at 0 (a, c) and 11 ns (b, d) in timescal...
Figure 5: (a) Distance between the O1 atom (CHL) and the centroid DK of the O4n atoms of host A at 300 (green...
Photocatalytic formation of carbon–sulfur bonds
- Alexander Wimmer and
- Burkhard König
Beilstein J. Org. Chem. 2018, 14, 54–83, doi:10.3762/bjoc.14.4
- available difluorobromoacetic acid. The respective carbon-centred radical intermediate is then oxidized by the [Ir] catalyst to close the catalytic cycle and form a reactive difluorocarbene intermediate by releasing carbon dioxide. At the same time, the aryl thiol is deprotonated by Cs2CO3. Finally, the
Graphical Abstract
Scheme 1: General overview over the sulfur-based substrates and reactive intermediates that are discussed in ...
Scheme 2: Photoredox-catalyzed radical thiol–ene reaction, applying [Ru(bpz)3](PF6)2 as photocatalyst.
Scheme 3: Photoredox-catalyzed thiol–ene reaction of aliphatic thiols with alkenes enabled by aniline derivat...
Scheme 4: Photoredox-catalyzed radical thiol–ene reaction for the postfunctionalization of polymers (a) and n...
Scheme 5: Photoredox-catalyzed thiol–ene reaction enabled by bromotrichloromethane as redox additive.
Scheme 6: Photoredox-catalyzed preparation of β-ketosulfoxides with Eosin Y as organic dye as photoredox cata...
Scheme 7: Greaney’s photocatalytic radical thiol–ene reaction, applying TiO2 nanoparticles as photocatalyst.
Scheme 8: Fadeyi’s photocatalytic radical thiol–ene reaction, applying Bi2O3 as photocatalyst.
Scheme 9: Ananikov’s photocatalytic radical thiol-yne reaction, applying Eosin Y as photocatalyst.
Scheme 10: Organocatalytic visible-light photoinitiated thiol–ene coupling, applying phenylglyoxylic acid as o...
Scheme 11: Xia’s photoredox-catalyzed synthesis of 2,3-disubstituted benzothiophenes, applying 9-mesityl-10-me...
Scheme 12: Wang’s metal-free photoredox-catalyzed radical thiol–ene reaction, applying 9-mesityl-10-methylacri...
Scheme 13: Visible-light benzophenone-catalyzed metal- and oxidant-free radical thiol–ene reaction.
Scheme 14: Visible-light catalyzed C-3 sulfenylation of indole derivatives using Rose Bengal as organic dye.
Scheme 15: Photocatalyzed radical thiol–ene reaction and subsequent aerobic sulfide-oxidation with Rose Bengal...
Scheme 16: Photoredox-catalyzed synthesis of diaryl sulfides.
Scheme 17: Photocatalytic cross-coupling of aryl thiols with aryl diazonium salts, using Eosin Y as photoredox...
Scheme 18: Photocatalyzed cross-coupling of aryl diazonium salts with cysteines in batch and in a microphotore...
Scheme 19: Fu’s [Ir]-catalyzed photoredox arylation of aryl thiols with aryl halides.
Scheme 20: Fu’s photoredox-catalyzed difluoromethylation of aryl thiols.
Scheme 21: C–S cross-coupling of thiols with aryl iodides via [Ir]-photoredox and [Ni]-dual-catalysis.
Scheme 22: C–S cross-coupling of thiols with aryl bromides, applying 3,7-bis-(biphenyl-4-yl)-10-(1-naphthyl)ph...
Scheme 23: Collin’s photochemical dual-catalytic cross-coupling of thiols with bromoalkynes.
Scheme 24: Visible-light-promoted C–S cross-coupling via intermolecular electron donor–acceptor complex format...
Scheme 25: Li’s visible-light photoredox-catalyzed thiocyanation of indole derivatives with Rose Bengal as pho...
Scheme 26: Hajra’s visible-light photoredox-catalyzed thiocyanation of imidazoheterocycles with Eosin Y as pho...
Scheme 27: Wang’s photoredox-catalyzed thiocyanation reaction of indoles, applying heterogeneous TiO2/MoS2 nan...
Scheme 28: Yadav’s photoredox-catalyzed α-C(sp3)–H thiocyanation reaction for tertiary amines, applying Eosin ...
Scheme 29: Yadav’s photoredox-catalyzed synthesis of 5-aryl-2-imino-1,3-oxathiolanes.
Scheme 30: Yadav’s photoredox-catalyzed synthesis of 1,3-oxathiolane-2-thiones.
Scheme 31: Li’s photoredox catalysis for the preparation of 2-substituted benzothiazoles, applying [Ru(bpy)3](...
Scheme 32: Lei’s external oxidant-free synthesis of 2-substituted benzothiazoles by merging photoredox and tra...
Scheme 33: Metal-free photocatalyzed synthesis of 2-aminobenzothiazoles, applying Eosin Y as photocatalyst.
Scheme 34: Metal-free photocatalyzed synthesis of 1,3,4-thiadiazoles, using Eosin Y as photocatalyst.
Scheme 35: Visible-light photoredox-catalyzed preparation of benzothiophenes with Eosin Y.
Scheme 36: Visible-light-induced KOH/DMSO superbase-promoted preparation of benzothiophenes.
Scheme 37: Jacobi von Wangelin’s photocatalytic approach for the synthesis of aryl sulfides, applying Eosin Y ...
Scheme 38: Visible-light photosensitized α-C(sp3)–H thiolation of aliphatic ethers.
Scheme 39: Visible-light photocatalyzed cross-coupling of alkyl and aryl thiosulfates with aryl diazonium salt...
Scheme 40: Visible-light photocatalyzed, controllable sulfenylation and sulfoxidation with organic thiosulfate...
Scheme 41: Rastogi’s photoredox-catalyzed methylsulfoxidation of aryl diazonium salts, using [Ru(bpy)3]Cl2 as ...
Scheme 42: a) Visible-light metal-free Eosin Y-catalyzed procedure for the preparation of vinyl sulfones from ...
Scheme 43: Visible-light photocatalyzed cross-coupling of sodium sulfinates with secondary enamides.
Scheme 44: Wang’s photocatalyzed oxidative cyclization of phenyl propiolates with sulfinic acids, applying Eos...
Scheme 45: Lei’s sacrificial oxidant-free synthesis of allyl sulfones by merging photoredox and transition met...
Scheme 46: Photocatalyzed Markovnikov-selective radical/radical cross-coupling of aryl sulfinic acids and term...
Scheme 47: Visible-light Eosin Y induced cross-coupling of aryl sulfinic acids and styrene derivatives, afford...
Scheme 48: Photoredox-catalyzed bicyclization of 1,7-enynes with sulfinic acids, applying Eosin Y as photocata...
Scheme 49: Visible-light-accelerated C–H-sulfinylation of arenes and heteroarenes.
Scheme 50: Visible-light photoredox-catalyzed β-selenosulfonylation of electron-rich olefins, applying [Ru(bpy)...
Scheme 51: Photocatalyzed preparation of β-chlorosulfones from the respective olefins and p-toluenesulfonyl ch...
Scheme 52: a) Photocatalyzed preparation of β-amidovinyl sulfones from sulfonyl chlorides. b) Preparation of β...
Scheme 53: Visible-light photocatalyzed sulfonylation of aliphatic tertiary amines, applying [Ru(bpy)3](PF6)2 ...
Scheme 54: Reiser’s visible-light photoredox-catalyzed preparation of β-hydroxysulfones from sulfonyl chloride...
Scheme 55: a) Sun’s visible-light-catalyzed approach for the preparation of isoquinolinonediones, applying [fac...
Scheme 56: Visible-light photocatalyzed sulfonylation/cyclization of vinyl azides, applying [Ru(bpy)3]Cl2 as p...
Scheme 57: Visible-light photocatalyzed procedure for the formation of β-ketosulfones from aryl sulfonyl chlor...
Scheme 58: Zheng’s method for the sulfenylation of indole derivatives, applying sulfonyl chlorides via visible...
Scheme 59: Cai’s visible-light induced synthesis of β-ketosulfones from sulfonyl hydrazines and alkynes.
Scheme 60: Photoredox-catalyzed approach for the preparation of vinyl sulfones from sulfonyl hydrazines and ci...
Scheme 61: Jacobi von Wangelin’s visible-light photocatalyzed chlorosulfonylation of anilines.
Scheme 62: Three-component photoredox-catalyzed synthesis of N-amino sulfonamides, applying PDI as organic dye....
Scheme 63: Visible-light induced preparation of complex sulfones from oximes, silyl enol ethers and SO2.
Synthesis and application of trifluoroethoxy-substituted phthalocyanines and subphthalocyanines
- Satoru Mori and
- Norio Shibata
Beilstein J. Org. Chem. 2017, 13, 2273–2296, doi:10.3762/bjoc.13.224
- phthalocyanines. TFEO-Pc is soluble not only in general organic solvents but also in liquid carbon dioxide (CO2) and supercritical CO2 [55]. These forms of CO2 have attracted attention as solvents which do not discharge volatile organic compounds (VOCs), and are expected to replace organic solvents as a
Graphical Abstract
Scheme 1: Synthesis of trifluoroethoxy-substituted phthalocyanine.
Scheme 2: Synthesis of trifluoroethoxy-substituted binuclear phthalocyanine 5 in Solkane® 365 mfc.
Scheme 3: Synthesis of trifluoroethoxy-substituted unsymmetrical phthalocyanines.
Scheme 4: Synthesis of trifluoroethoxy-substituted phthalocyanine dimers linked at the β-position.
Figure 1: Structure of trifluoroethoxy-substituted phthalocyanine dimers linked at the α-position.
Figure 2: Structure of trifluoroethoxy-substituted dimer via a diacetylene linker.
Figure 3: UV–vis spectra of 9 (A) and 5 (B).
Figure 4: Structure of binuclear phthalocyanines linked by a triazole linker.
Figure 5: Structure of trinuclear phthalocyanines linked by a triazole linker, and windmill-like molecular st...
Scheme 5: Synthesis of trifluoroethoxy-substituted phthalocyanines conjugated with peptides.
Scheme 6: Synthesis of trifluoroethoxy-substituted phthalocyanines conjugated with deoxyribonucleosides.
Scheme 7: Synthesis of trifluoroethoxy-substituted phthalocyanines conjugated with cyclodextrin.
Figure 6: Direction of energy transfer of phthalocyanine–fullerene conjugates.
Scheme 8: Synthesis of fluoropolymer-bearing phthalocyanine side groups.
Scheme 9: Synthesis of trifluoroethoxy-substituted double-decker type phthalocyanines.
Scheme 10: Synthesis of trifluoroethoxy-substituted subphthalocyanine.
Figure 7: Structure of axial ligand substituted subphthalocyanine hybrid dyes.
Scheme 11: Synthesis of subphthalocyanine homodimers.
Scheme 12: Synthesis of subphthalocyanine heterodimers.
Figure 8: Energy transfer between subphthalocyanine units.
Figure 9: Structure of phthalocyanine and subphthalocyanine benzene-fused homodimers.
Scheme 13: Synthesis of a phthalocyanine and subphthalocyanine benzene-fused heterodimer.
Figure 10: X-ray crystallography of Pc-subPc (left) and UV–vis spectra of benzene-fused dimers.
Phosphonic acid: preparation and applications
- Charlotte M. Sevrain,
- Mathieu Berchel,
- Hélène Couthon and
- Paul-Alain Jaffrès
Beilstein J. Org. Chem. 2017, 13, 2186–2213, doi:10.3762/bjoc.13.219
- ] pointing out the importance of such type of compounds in natural biochemical processes [36]. Phosphonic acid mimics the phosphate group, which is omnipresent in nature, but also the tetrahedral transition-state intermediate encountered for instance during the hydratation of carbon dioxide by carbonic
Graphical Abstract
Figure 1: Summary of the synthetic routes to prepare phosphonic acids detailed in this review. The numbers in...
Figure 2: Chemical structure of dialkyl phosphonate, phosphonic acid and illustration of the simplest phospho...
Figure 3: Illustration of some phosphonic acid exhibiting bioactive properties. A) Phosphonic acids for biome...
Figure 4: Illustration of the use of phosphonic acids for their coordination properties and their ability to ...
Figure 5: Hydrolysis of dialkyl phosphonate to phosphonic acid under acidic conditions.
Figure 6: Examples of phosphonic acids prepared by hydrolysis of dialkylphosphonate with HCl 35% at reflux (16...
Figure 7: A) and B) Observation of P–C bond breaking during the hydrolysis of phosphonate with concentrated H...
Figure 8: Mechanism of the hydrolysis of dialkyl phosphonate with HCl in water.
Figure 9: Hydrolysis of bis-tert-butyl phosphonate 28 into phosphonic acid 29 [137].
Figure 10: A) Hydrolysis of diphenyl phosphonate into phosphonic acid in acidic media. B) Examples of phosphon...
Figure 11: Suggested mechanism occurring for the first step of the hydrolysis of diphenyl phosphonate into pho...
Figure 12: A) Hydrogenolysis of dibenzyl phosphonate to phosphonic acid. B) Compounds 33, 34 and 35 were prepa...
Figure 13: A) Preparation of phosphonic acid from diphenyl phosphonate with the Adam’s catalyst. B) Compounds ...
Figure 14: Suggested mechanism for the preparation of phosphonic acid from dialkyl phosphonate using bromotrim...
Figure 15: A) Reaction of the phosphonate-thiophosphonate 37 with iodotrimethylsilane followed by methanolysis...
Figure 16: Synthesis of hydroxymethylenebisphosphonic acid by reaction of tris(trimethylsilyl) phosphite with ...
Figure 17: Synthesis of the phosphonic acid disodium salt 48 by reaction of mono-hydrolysed phosphonate 47 wit...
Figure 18: Phosphonic acid synthesized by the sequence 1) bromotrimethylsilane 2) methanolysis or hydrolysis. ...
Figure 19: Polyphosphonic acids and macromolecular compounds prepared by the hydrolysis of dialkyl phosphonate...
Figure 20: Examples of organometallic complexes functionalized with phosphonic acids that were prepared by the...
Figure 21: Side reaction observed during the hydrolysis of methacrylate monomer functionalized with phosphonic...
Figure 22: Influence of the reaction time during the hydrolysis of compound 76.
Figure 23: Dealkylation of dialkyl phosphonates with boron tribromide.
Figure 24: Dealkylation of diethylphosphonate 81 with TMS-OTf.
Figure 25: Synthesis of substituted phenylphosphonic acid 85 from the phenyldichlorophosphine 83.
Figure 26: Hydrolysis of substituted phenyldichlorophosphine oxide 86 under basic conditions.
Figure 27: A) Illustration of the synthesis of chiral phosphonic acids from phosphonodiamides. B) Examples of ...
Figure 28: A) Illustration of the synthesis of the phosphonic acid 98 from phosphonodiamide 97. B) Use of cycl...
Figure 29: Synthesis of tris(phosphonophenyl)phosphine 109.
Figure 30: Moedritzer–Irani reaction starting from A) primary amine or B) secondary amine. C) Examples of phos...
Figure 31: Phosphonic acid-functionalized polymers prepared by Moedritzer–Irani reaction.
Figure 32: Reaction of phosphorous acid with imine in the absence of solvent.
Figure 33: A) Reaction of phosphorous acid with nitrile and examples of aminomethylene bis-phosphonic acids. B...
Figure 34: Reaction of carboxylic acid with phosphorous acid and examples of compounds prepared by this way.
Figure 35: Synthesis of phosphonic acid by oxidation of phosphinic acid (also identified as phosphonous acid).
Figure 36: Selection of reaction conditions to prepare phosphonic acids from phosphinic acids.
Figure 37: Synthesis of phosphonic acid from carboxylic acid and white phosphorus.
Figure 38: Synthesis of benzylphosphonic acid 136 from benzaldehyde and red phosphorus.
Figure 39: Synthesis of graphene phosphonic acid 137 from graphite and red phosphorus.
Novel approach to hydroxy-group-containing porous organic polymers from bisphenol A
- Tao Wang,
- Yan-Chao Zhao,
- Li-Min Zhang,
- Yi Cui,
- Chang-Shan Zhang and
- Bao-Hang Han
Beilstein J. Org. Chem. 2017, 13, 2131–2137, doi:10.3762/bjoc.13.211
- exhibit a highest carbon dioxide uptake (up to 15.0 wt % (273 K) and 8.8 wt % (298 K) at 1.0 bar), and possess moderate hydrogen storage capacities ranging from 1.28 to 1.04 wt % (77 K) at 1.0 bar. Moreover, the highest uptake of methane for the PPOPs is measured as 4.3 wt % (273 K) at 1.0 bar. Keywords
- : bisphenol A; carbon dioxide uptake; hydrogen storage; OH-containing; porous organic polymers; Introduction Porous organic polymers standing out from kinds of porous materials such as zeolite, activated carbon, metal-organic frameworks [1][2], and covalent organic frameworks [3][4], with their prominent
- p-toluenesulfonic acid (TSA) as catalyst that has been proved to be a non-metallic acidic catalyst with high efficiency [26][27]. The materials exhibit Brunauer–Emmet–Teller (BET) specific surface area values ranging from 720 to 920 m2 g–1, and the highest carbon dioxide uptake is up to 15.0 wt % at
Graphical Abstract
Scheme 1: Schematic representation of the possible structures of bisphenol-A-based porous organic polymers.
Figure 1: FTIR spectra of terephthalic aldehyde (M1), BPA, and PPOP-1.
Figure 2: Solid-state 13C CP/MAS NMR spectrum of PPOP-1 recorded at the MAS rate of 5 kHz.
Figure 3: (a) Nitrogen adsorption–desorption isotherms of PPOP-1 (downtriangle), PPOP-2 (circle), and PPOP-3 ...
Figure 4: Gravimetric gas adsorption isotherms for PPOP-1 (downtriangle), PPOP-2 (circle), and PPOP-3 (square...
Figure 5: Variation of isosteric heat of adsorption with amount of adsorbed CO2 in PPOP-1, PPOP-2, and PPOP-3....
Detection of therapeutic radiation in three-dimensions
- John A. Adamovics
Beilstein J. Org. Chem. 2017, 13, 1325–1331, doi:10.3762/bjoc.13.129
- reactants, introducing the resulting solution into a mold; then allowing the polymer to cure at ambient temperature (>20 °C) in a pressure tank (30–60 psi). Performance of the reaction under pressure eliminates formation bubbles of carbon dioxide which is formed as a byproduct of the reaction of
Graphical Abstract
Scheme 1: Ionizing radiation reactions in the Fricke dosimeter.
Figure 1: Structure of xylenol orange.
Scheme 2: Sulfuric acid/urea promoted synthesis of LMG.
Figure 2: Aliphatic diisocyantes HMDI, HDI, IPDI.
Figure 3: Absorption spectrum of irradiated leucomalachite green.
Figure 4: 3D dosimeters fabricated in our lab for a variety of radiation therapies. Top left a head dosimeter...
Figure 5: OCT scanner used in our lab to create 3D images.
Sugar-based micro/mesoporous hypercross-linked polymers with in situ embedded silver nanoparticles for catalytic reduction
- Qing Yin,
- Qi Chen,
- Li-Can Lu and
- Bao-Hang Han
Beilstein J. Org. Chem. 2017, 13, 1212–1221, doi:10.3762/bjoc.13.120
- to tune the porosity. These obtained polymers exhibit microporous and mesoporous features. The highest Brunauer–Emmett–Teller specific surface area for the resulting polymers was found to be 1220 m2 g−1, and the related carbon dioxide storage capacity was found to be 14.4 wt % at 1.0 bar and 273 K
- microporous HCPs based on carbohydrates for carbon dioxide capture and storage by hydrogen bonding and dipole–quadrupole interactions [17]. The reported pore-size distribution (PSD) and related porosity tuning are in the range of micropore size. Considering that the polyhydroxylated and chiral structure
- (Supporting Information File 1). The polymer SugPOP-1 having a higher SSA and pore volume also exhibits a higher CO2 adsorption capacity (14.4 wt %) than SugPOP-2 (12.8 wt %) and SugPOP-3 (10.5 wt %). Additionally, the hydroxy-group-bearing SugPOP-1 can form hydrogen bonds with carbon dioxide, which may
Graphical Abstract
Scheme 1: Preparation of polymers SugPOP-1–3 (FDA: formaldehyde dimethyl acetal).
Figure 1: 13C CP/MAS NMR spectrum of SugPOP-3.
Figure 2: (a) Nitrogen adsorption–desorption isotherms of SugPOP-1–3 measured at 77 K. For clarity, the isoth...
Scheme 2: The preparation of AgNPs/SugPOP-1 composite by the in situ production of AgNPs.
Figure 3: TEM images of the AgNPs/SugPOP-1 composite taken at different reaction times: (a) 0 h, (b) 8 h; (c)...
Figure 4: Nitrogen sorption isotherm at 77 K and the pore size distribution profile calculated by NLDFT analy...
Figure 5: Catalytic performance of the AgNPs/SugPOP-1 composite. Time-dependent UV–vis spectral changes (a) a...
From chemical metabolism to life: the origin of the genetic coding process
- Antoine Danchin
Beilstein J. Org. Chem. 2017, 13, 1119–1135, doi:10.3762/bjoc.13.111
- scenarios. To be sure, trying to understand the origins of life should be based on what we know of current chemistry in the solar system and beyond. There, amino acids and very small compounds such as carbon dioxide, dihydrogen or dinitrogen and their immediate derivatives are ubiquitous. Surface-based
- aromatic heterocycles) is based on the incorporation of amino acids in the core of nucleotide precursors. Pyrimidine nucleotide biosynthesis uses aspartate and combines together ubiquitous molecules, water, carbon dioxide, ammonium and phosphate (forming carbamoyl phosphate, also a precursor of arginine
Graphical Abstract
Figure 1: Selective surface metabolism. Prebiotic carbon-based molecules accumulated in a neutral or slightly...
Figure 2: Building up membranes, peptides and co-enzymes. Thioester-based metabolism resulted in the synthesi...
Figure 3: The RNA metabolism world. Among molecules built up by a swinging-arm thioester are pyrimidines coup...
The effect of cyclodextrin complexation on the solubility and photostability of nerolidol as pure compound and as main constituent of cabreuva essential oil
- Joyce Azzi,
- Pierre-Edouard Danjou,
- David Landy,
- Steven Ruellan,
- Lizette Auezova,
- Hélène Greige-Gerges and
- Sophie Fourmentin
Beilstein J. Org. Chem. 2017, 13, 835–844, doi:10.3762/bjoc.13.84
- investigated by TOC analysis using a Shimadzu TOC-VCSH analyzer. It is based on the production of carbon dioxide (CO2) following oxidation of organic compounds. CO2 is then detected using a high-sensitivity infrared gas analyzer (NDIR). First, TOC was measured for the CD solution (TOCCD). Then, the amount of
Graphical Abstract
Figure 1: Chemical structure of β-CD (a) and β-CD derivatives (b).
Figure 2: Phase solubility diagrams of CD/trans-Ner inclusion complexes.
Figure 3: Phase solubility profile of cabreuva EO obtained by the TOC method.
Figure 4: a) 2D ROESY spectrum of β-CD/trans-Ner inclusion complex in D2O and b) representation of the most s...
Figure 5: Photodegradation kinetics of cis-Ner (a), trans-Ner (b), the isomer mixture Ner (c) in the absence ...
Conjecture and hypothesis: The importance of reality checks
- David Deamer
Beilstein J. Org. Chem. 2017, 13, 620–624, doi:10.3762/bjoc.13.60
- chimney structures. The hydrogen gas dissolved in the alkaline vent fluid is a potential source of reducing power. Certain microorganisms already use hydrogen for this purpose, so the hydrothermal vent hypothesis proposes that on the prebiotic Earth hydrogen could potentially reduce carbon dioxide to
- vent conditions by injecting a solution of potassium phosphate, sodium silicate and sodium sulfide (pH 11) into a second solution of ferrous chloride, sodium bicarbonate and nickel chloride (pH 5). The aim was to determine whether carbon dioxide (present as 10 mM sodium bicarbonate) can be reduced
Adsorption of RNA on mineral surfaces and mineral precipitates
- Elisa Biondi,
- Yoshihiro Furukawa,
- Jun Kawai and
- Steven A. Benner
Beilstein J. Org. Chem. 2017, 13, 393–404, doi:10.3762/bjoc.13.42
- . These are interesting not only because carbon dioxide is likely to have been an abundant component of an early Earth atmosphere, but also because alkaline earths form a well-known set of binary carbonates that include insoluble magnesium, calcium, strontium, and barium carbonates (magnesite, calcite
Graphical Abstract
Figure 1: Adsorption of RNA on natural carbonate mineral samples.
Figure 2: Co-precipitation experiments on carbonate minerals for RNA-binding competition. The precipitated co...
Figure 3: RNA-induced calcium carbonate polymorphism. A: Feigl’s stain of CaCO3 precipitate formed by double ...
Figure 4: RNA adsorbed on aragonite is resistant to thermal degradation in aqueous solution. 18% denaturing P...
Decarboxylative and dehydrative coupling of dienoic acids and pentadienyl alcohols to form 1,3,6,8-tetraenes
- Ghina’a I. Abu Deiab,
- Mohammed H. Al-Huniti,
- I. F. Dempsey Hyatt,
- Emma E. Nagy,
- Kristen E. Gettys,
- Sommayah S. Sayed,
- Christine M. Joliat,
- Paige E. Daniel,
- Rupa M. Vummalaneni,
- Andrew T. Morehead Jr,
- Andrew L. Sargent and
- Mitchell P. Croatt
Beilstein J. Org. Chem. 2017, 13, 384–392, doi:10.3762/bjoc.13.41
- accessible alcohol for a leaving group. This reaction was advanced to be possible in a two-component fashion, allowing for the conversion of dienoic acids and pentadienyl alcohols into 1,3,6,8-tetraenes with the only stoichiometric byproducts being water and carbon dioxide. These reactions currently require
Graphical Abstract
Scheme 1: Prior and current decarboxylative couplings.
Scheme 2: Esters examined in the decarboxylation reaction.
Scheme 3: Possible mechanistic pathways.
Figure 1: Calculated HOMO of transition state between E and F.
Continuous N-alkylation reactions of amino alcohols using γ-Al2O3 and supercritical CO2: unexpected formation of cyclic ureas and urethanes by reaction with CO2
- Emilia S. Streng,
- Darren S. Lee,
- Michael W. George and
- Martyn Poliakoff
Beilstein J. Org. Chem. 2017, 13, 329–337, doi:10.3762/bjoc.13.36
- toxic solvents; furthermore post-reaction separation is simplified as the gas/liquid phases separate upon cooling. The use of supercritical methanol (scMeOH) for N-alkylation reactions has been reported before [29][30]. Our own investigations with heterogeneous catalysis in supercritical carbon dioxide
Graphical Abstract
Scheme 1: Target reaction – intramolecular cyclisation of 1 followed by N-methylation with methanol to yield ...
Figure 1: Simplified schematic demonstrating a self-optimising reactor [34,35,37,44]. The reagents are pumped into the sys...
Figure 2: Result of the SNOBFIT optimisation for N-methylpiperidine (2b) with and without CO2 showing yields ...
Scheme 2: Cyclisation and N-alkylation of 1,4- and 1,6-amino alcohols.
Scheme 3: a) Reactions highlighting the incorporation of CO2 in to 16. b) High temperature reaction of 15 yie...
Scheme 4: Summary of products obtained from the reactions of amino alcohols over γ-Al2O3 in scCO2.
Figure 3: Diagram of the high pressure equipment used in the experiments.
Diastereoselective anodic hetero- and homo-coupling of menthol-, 8-methylmenthol- and 8-phenylmenthol-2-alkylmalonates
- Matthias C. Letzel,
- Hans J. Schäfer and
- Roland Fröhlich
Beilstein J. Org. Chem. 2017, 13, 33–42, doi:10.3762/bjoc.13.5
- the benzyl ester 19 with lithium diisopropylamide and quenching the enolate with carbon dioxide (Scheme 2a). Benzyl 2-tert-butylmalonate (6) was prepared in good yield using a method of Krapcho et al. [18], by double deprotonation of 3,3-dimethylbutyric acid (20) with LDA and quenching the dianion
Graphical Abstract
Figure 1: Menthol auxiliaries 1–4 used in the following anodic coupling reactions.
Scheme 1: Synthesis of carboxylic acids 13a/b–18a/b.
Scheme 2: (a) Preparation of benzyl 2-isopropylmalonate (5) and (b) preparation of benzyl 2-tert-butylmalonat...
Scheme 3: Coelectrolysis (hetero-coupling) of carboxylic acids 13–17 with 3,3-dimethylbutyric acid (20).
Figure 2: Crystal structure of the minor diastereomer 23b.
Figure 3: Cyclic voltammograms of the malonic derivatives 15a/b, 16a/b and 18a/b (scan rate: 500 mA/s, solven...
Scheme 4: Homo-coupling of carboxylic acids 13a/b–16a/b to diesters 26a/b/c–29a/b/c (n.d.: not determined).
Figure 4: Crystal structure of major diastereomer 28a.
Figure 5: Crystal structure of major diastereomer 29a.
Figure 6: Discrimination of diastereomeric faces in the menthol substituted radical A and in the 8-phenylment...
Scheme 5: Reductive cleavage of 30a–c to 8-phenylmenthol (3) and 31a–c.
Catalytic Wittig and aza-Wittig reactions
- Zhiqi Lao and
- Patrick H. Toy
Beilstein J. Org. Chem. 2016, 12, 2577–2587, doi:10.3762/bjoc.12.253
- carbon dioxide (2 equivalents). While this reaction was described as being catalytic, the mass of the catalyst used was not explicitly reported, so it is impossible to determine the number of catalyst turnovers that were involved in generating the 20% isolated yield of 43. The authors only reported that
- ]. In this work, biaryl isocyanates 45 could be converted into phenanthridines 46, and aryl isocyanates 47 could be transformed into benzoxazoles 48 directly in refluxing toluene together with the simultaneous release of carbon dioxide. Presumably these reactions proceeded via iminophosphorane
Graphical Abstract
Scheme 1: Prototypical Wittig reaction involving in situ phosphonium salt and phosphonium ylide formation.
Scheme 2: Bu3As-catalyzed Wittig-type reactions.
Scheme 3: Ph3As-catalyzed Wittig-type reactions using Fe(TCP)Cl and ethyl diazoacetate for arsonium ylide gen...
Figure 1: Recyclable polymer-supported arsine for catalytic Wittig-type reactions.
Scheme 4: Bu2Te-catalyzed Wittig-type reactions.
Scheme 5: Polymer-supported telluride catalyst cycling.
Scheme 6: Stable and odourless telluronium salt pre-catalyst for Wittig-type reactions.
Scheme 7: Phosphine-catalyzed Wittig reactions.
Figure 2: Various phosphine oxides used as pre-catalysts.
Scheme 8: Enantioselective catalytic Wittig reaction reported by Werner.
Scheme 9: Base-free catalytic Wittig reactions reported by Werner.
Scheme 10: Catalytic Wittig reactions reported by Lin.
Scheme 11: Catalytic Wittig reactions reported by Plietker.
Scheme 12: Prototypical aza-Wittig reaction involving in situ iminophosphorane formation.
Scheme 13: First catalytic aza-Wittig reaction reported by Campbell.
Scheme 14: Intramolecular catalytic aza-Wittig reactions reported by Marsden.
Scheme 15: Catalytic aza-Wittig reactions in 1,4-benzodiazepin-5-one synthesis.
Scheme 16: Catalytic aza-Wittig reactions in benzimidazole synthesis.
Scheme 17: Phosphine-catalyzed Staudinger and aza-Wittig reactions.
Scheme 18: Catalytic aza-Wittig reactions in 4(3H)-quinazolinone synthesis.
Scheme 19: Catalytic aza-Wittig reactions of in situ generated carboxylic acid anhydrides.
Scheme 20: Phosphine-catalyzed diaza-Wittig reactions.
A new paradigm for designing ring construction strategies for green organic synthesis: implications for the discovery of multicomponent reactions to build molecules containing a single ring
- John Andraos
Beilstein J. Org. Chem. 2016, 12, 2420–2442, doi:10.3762/bjoc.12.236
- either of carbon monoxide [141][142][143], carbon dioxide [144], dichloromethoxymethane [145][146], or methyl methylthiomethyl sulfoxide [147][148][149] as one-carbon fragments. The only literature example of a [4 + 2] strategy applied to cyclohexanone derivatives involved reaction of but-3-en-2-one with
Graphical Abstract
Figure 1: Possible two-component couplings for various monocyclic rings frequently encountered in organic mol...
Figure 2: Possible three-component couplings for various monocyclic rings frequently encountered in organic m...
Figure 3: Possible four-component couplings for various monocyclic rings frequently encountered in organic mo...
Figure 4: Permutations of two-component coupling patterns for synthesizing the cyclohexanone ring. Synthesis ...
Figure 5: Permutations of two-component coupling patterns for synthesizing the cyclohexanone ring overlayed w...
Scheme 1: Conjectured syntheses of cyclohexanone via [5 + 1] strategies.
Scheme 2: Conjectured syntheses of cyclohexanone via [4 + 2] strategies.
Scheme 3: Conjectured syntheses of cyclohexanone via [3 + 3] strategies.
Figure 6: Permutations of three-component coupling patterns for synthesizing the cyclohexanone ring. Synthesi...
Figure 7: Permutations of three-component coupling patterns for synthesizing the pyrazole ring via [2 + 2 + 1...
Scheme 4: Literature method for constructing the pyrazole ring via the A4 [2 + 2 + 1] strategy.
Scheme 5: Literature methods for constructing the pyrazole ring via the A5 [2 + 2 + 1] strategy.
Scheme 6: Literature methods for constructing the pyrazole ring via the A1 [2 + 2 + 1] strategy.
Scheme 7: Literature methods for constructing the pyrazole ring via the B4 [3 + 1 + 1] strategy.
Figure 8: Intrinsic green performance of documented pyrazole syntheses according to [2 + 2 + 1] and [3 + 1 + ...
Scheme 8: Conjectured reactions for constructing the pyrazole ring via the A2 and A3 [2 + 2 + 1] strategies.
Scheme 9: Conjectured reactions for constructing the pyrazole ring via the B1, B2, B3, and B4 [3 + 1 + 1] str...
Figure 9: Permutations of three-component coupling patterns for synthesizing the Biginelli ring adduct. Synth...
Scheme 10: Reported syntheses of the Biginelli adduct via the traditional [3 + 2 + 1] mapping strategy.
Scheme 11: Reported syntheses of the Biginelli adduct via new [3 + 2 + 1] mapping strategies.
Scheme 12: Reported syntheses of the Biginelli adduct via a new [2 + 2 + 1 + 1] mapping strategy.
Scheme 13: Conjectured syntheses of the Biginelli adduct via new [2 + 2 + 2] mapping strategies.
Scheme 14: Conjectured syntheses of the Biginelli adduct via new [3 + 2 + 1] mapping strategies.
Figure 10: Intrinsic green performance of documented Biginelli adduct syntheses according to [3 + 2 + 1] three...
Figure 11: Intrinsic green performance of newly conjectured Biginelli adduct syntheses according to [4 + 1 + 1...
Robust C–C bonded porous networks with chemically designed functionalities for improved CO2 capture from flue gas
- Damien Thirion,
- Joo S. Lee,
- Ercan Özdemir and
- Cafer T. Yavuz
Beilstein J. Org. Chem. 2016, 12, 2274–2279, doi:10.3762/bjoc.12.220
- Technology (KAIST), Guseong Dong, Yuseong Gu, Daejeon 305–701, Korea 10.3762/bjoc.12.220 Abstract Effective carbon dioxide (CO2) capture requires solid, porous sorbents with chemically and thermally stable frameworks. Herein, we report two new carbon–carbon bonded porous networks that were synthesized
Graphical Abstract
Scheme 1: Synthesis route for COP-156 and COP-157, and the post-modification of COP-156.
Figure 1: FTIR spectra of COP-156 (black), COP-156-amine (blue) and COP-156-amidoxime (red). The dotted lines...
Figure 2: Gas adsorption (filled dots)-desorption (empty dots) isotherms and pore size distribution of COP-15...
Figure 3: CO2 uptake under moist conditions at 40 °C of COP-156 (black) and COP-156-amine (blue).
Hydroxy-functionalized hyper-cross-linked ultra-microporous organic polymers for selective CO2 capture at room temperature
- Partha Samanta,
- Priyanshu Chandra and
- Sujit K. Ghosh
Beilstein J. Org. Chem. 2016, 12, 1981–1986, doi:10.3762/bjoc.12.185
- 10.3762/bjoc.12.185 Abstract Two hydroxy-functionalized hyper-cross-linked ultra-microporous compounds have been synthesized by Friedel–Crafts alkylation reaction and characterised with different spectroscopic techniques. Both compounds exhibit an efficient carbon dioxide uptake over other gases like N2
- , H2 and O2 at room temperature. A high isosteric heat of adsorption (Qst) has been obtained for both materials because of strong interactions between polar –OH groups and CO2 molecules. Keywords: carbon dioxide capture; hyper-cross-linked polymer; metal-organic framework; microporous organic polymer
- of hundred years in contrast to other greenhouse gases which leave the atmosphere with relatively smaller time scale [1]. The CO2 long life in the atmosphere provides the clearest possible rationale for carbon dioxide capture and storage. Previously, different types of amine solvents were employed to
Graphical Abstract
Scheme 1: Schematic representation of selective CO2 capture in a porous material.
Figure 1: a) General synthesis scheme for hyper-cross-linked polymers (HCPs) and b) synthesis schemes for HCP...
Figure 2: a) Infra-red spectra of HCP-91 (dark yellow) and HCP-94 (purple); b) N2 adsorption isotherms for HC...
Figure 3: a) CO2 adsorption isotherms for HCP-91 (purple) and HCP-94 (green) at 195 K; b) adsorption isotherm...
Ionic liquids as transesterification catalysts: applications for the synthesis of linear and cyclic organic carbonates
- Maurizio Selva,
- Alvise Perosa,
- Sandro Guidi and
- Lisa Cattelan
Beilstein J. Org. Chem. 2016, 12, 1911–1924, doi:10.3762/bjoc.12.181
- of oxygen and a palladium catalyst (Scheme 6, middle). Though safer than the phosgenation of methanol, these synthetic routes still involved poisonous carbon monoxide and methyl nitrite, and chlorine-based catalysts. Carbon dioxide is the natural green alternative carbonyl source to these undesirable
- feedstocks, in particular to CO, except that its thermodynamic stability poses severe challenges. This potential limitation was overcome by the Asahi Kasei Corp. that recently industrialized a catalytic polycarbonate production process based on the use of carbon dioxide (CO2) for the synthesis of DMC as an
Graphical Abstract
Scheme 1: The transesterification of diethyl oxalate (DEO) with phenol catalyzed by MoO3/SiO2.
Scheme 2: Transesterification of a triglyceride (TG) with DMC for biodiesel production using KOH as the base ...
Scheme 3: Top: Green methylation of phosphines and amines by dimethyl carbonate (Q = N, P). Bottom: anion met...
Figure 1: Structures of some representative SILs and PILs systems. MCF is a silica-based mesostructured mater...
Scheme 4: Synthesis of the acid polymeric IL. EGDMA: ethylene glycol dimethacrylate.
Scheme 5: The transesterification of sec-butyl acetate with MeOH catalyzed by some acidic imidazolium ILs.
Figure 2: Representative examples of ionic liquids for biodiesel production.
Scheme 6: Top: phosgenation of methanol; middle: EniChem and Ube processes; bottom: Asahi process for the pro...
Scheme 7: The transesterification in the synthesis of organic carbonates.
Scheme 8: The transesterification of DMC with alcohols and diols.
Scheme 9: Transesterification of glycerol with DMC in the presence of 1-n-butyl-3-methylimidazolium-2-carboxy...
Scheme 10: Synthesis of the BMIM-2-CO2 catalyst from butylimidazole and DMC.
Scheme 11: Plausible cooperative (nucleophilic–electrophilic) mechanism for the transesterification of glycero...
Scheme 12: Synthesis of diazabicyclo[5.4.0]undec-7-ene-based ionic liquids.
Scheme 13: Synthesis of the DABCO–DMC ionic liquid.
Scheme 14: Cooperative mechanism of ionic liquid-catalyzed glycidol production.
Scheme 15: [TMA][OH]-catalyzed synthesis of glycidol (GD) from glycerol and dimethyl carbonate [46].
Scheme 16: [BMIM]OH-catalyzed synthesis of DPC from DMC and 1-pentanol.
Figure 3: Representative examples of ionic liquids for biodiesel production.
Figure 4: Acyclic non-symmetrical organic carbonates synthetized with 1-(trimethoxysilyl)propyl-3-methylimida...
Scheme 17: A simplified reaction mechanism for DMC production.
Scheme 18: [P8881][MeOCO2] metathesis with acetic acid and phenol.
Figure 5: Examples of carbonates obtained through transesterification using phosphonium salts as catalysts.
Scheme 19: Examples of carbonates obtained from different bio-based diols using [P8881][CH3OCO2] as catalyst.
Scheme 20: Ambiphilic catalysis for transesterification reactions in the presence of carbonate phosphonium sal...
Rearrangements of organic peroxides and related processes
- Ivan A. Yaremenko,
- Vera A. Vil’,
- Dmitry V. Demchuk and
- Alexander O. Terent’ev
Beilstein J. Org. Chem. 2016, 12, 1647–1748, doi:10.3762/bjoc.12.162
- of luciferin yields the peroxy compound 1,2-dioxetane. This four-membered peroxide cycle is unstable and spontaneously decays to carbon dioxide and excited ketones, which release excess energy through light emission (bioluminescence) [62][63][64][65]. The in vivo oxidation of cholesterol by singlet
Graphical Abstract
Figure 1: The named transformations considered in this review.
Scheme 1: The Baeyer–Villiger oxidation.
Scheme 2: The general mechanism of the peracid-promoted Baeyer–Villiger oxidation.
Scheme 3: General mechanism of the Lewis acid-catalyzed Baeyer–Villiger rearrangement.
Scheme 4: The theoretically studied mechanism of the BV oxidation reaction promoted by H2O2 and the Lewis aci...
Scheme 5: Proton movements in the transition states of the Baeyer–Villiger oxidation.
Scheme 6: The dependence of the course of the Baeyer–Villiger oxidation on the type of O–O-bond cleavage in t...
Scheme 7: The acid-catalyzed Baeyer–Villiger oxidation of cyclic epoxy ketones 22.
Scheme 8: Oxidation of isophorone oxide 29.
Scheme 9: Synthesis of acyl phosphate 32 from acyl phosphonate 31.
Scheme 10: Synthesis of aflatoxin B2 (36).
Scheme 11: The Baeyer–Villiger rearrangement of ketones 37 to lactones 38.
Scheme 12: Synthesis of 3,4-dimethoxybenzoic acid (40) via Baeyer–Villiger oxidation.
Scheme 13: Oxone transforms α,β-unsaturated ketones 43 into vinyl acetates 44.
Scheme 14: The Baeyer–Villiger oxidation of ketones 45 using diaryl diselenide and hydrogen peroxide.
Scheme 15: Baeyer–Villiger oxidation of (E)-2-methylenecyclobutanones.
Scheme 16: Oxidation of β-ionone (56) by H2O2/(BnSe)2 with formation of (E)-2-(2,6,6-trimethylcyclohex-1-en-1-...
Scheme 17: The mechanism of oxidation of ketones 58a–f by hydrogen peroxide in the presence of arsonated polys...
Scheme 18: Oxidation of ketone (58b) by H2O2 to 6-methylcaprolactone (59b) catalyzed by Pt complex 66·BF4.
Scheme 19: Oxidation of ketones 67 with H2O2 in the presence of [(dppb}Pt(µ-OH)]22+.
Scheme 20: The mechanism of oxidation of ketones 67 in the presence of [(dppb}Pt(µ-OH)]22+ and H2O2.
Scheme 21: Oxidation of benzaldehydes 69 in the presence of the H2O2/MeReO3 system.
Scheme 22: Oxidation of acetophenones 72 in the presence of the H2O2/MeReO3 system.
Scheme 23: Baeyer–Villiger oxidation of 2-adamantanone (45c) in the presence of Sn-containing mesoporous silic...
Scheme 24: Aerobic Baeyer–Villiger oxidation of ketones 76 using metal-free carbon.
Scheme 25: A regioselective Baeyer-Villiger oxidation of functionalized cyclohexenones 78 into a dihydrooxepin...
Scheme 26: The oxidation of aldehydes and ketones 80 by H2O2 catalyzed by Co4HP2Mo15V3O62.
Scheme 27: The cleavage of ketones 82 with hydrogen peroxide in alkaline solution.
Scheme 28: Oxidation of ketones 85 to esters 86 with H2O2–urea in the presence of KHCO3.
Scheme 29: Mechanism of the asymmetric oxidation of cyclopentane-1,2-dione 87a with the Ti(OiPr)4/(+)DET/t-BuO...
Scheme 30: The oxidation of cis-4-tert-butyl-2-fluorocyclohexanone (93) with m-chloroperbenzoic acid.
Scheme 31: The mechanism of the asymmetric oxidation of 3-substituted cyclobutanone 96a in the presence of chi...
Scheme 32: Enantioselective Baeyer–Villiger oxidation of cyclic ketones 98.
Scheme 33: Regio- and enantioselective Baeyer–Villiger oxidation of cyclic ketones 101.
Scheme 34: The proposed mechanism of the Baeyer–Villiger oxidation of acetal 105f.
Scheme 35: Synthesis of hydroxy-10H-acridin-9-one 117 from tetramethoxyanthracene 114.
Scheme 36: The Baeyer–Villiger oxidation of the fully substituted pyrrole 120.
Scheme 37: The Criegee rearrangement.
Scheme 38: The mechanism of the Criegee reaction of a peracid with a tertiary alcohol 122.
Scheme 39: Criegee rearrangement of decaline ethylperoxoate 127 into ketal 128.
Scheme 40: The ionic cleavage of 2-methoxy-2-propyl perester 129.
Scheme 41: The Criegee rearrangement of α-methoxy hydroperoxide 136.
Scheme 42: Synthesis of enol esters and acetals via the Criegee rearrangement.
Scheme 43: Proposed mechanism of the transformation of 1-hydroperoxy-2-oxabicycloalkanones 147a–d.
Scheme 44: Transformation of 3-hydroxy-1,2-dioxolanes 151 into diketone derivatives 152.
Scheme 45: Criegee rearrangement of peroxide 153 with the mono-, di-, and tri-O-insertion.
Scheme 46: The sequential Criegee rearrangements of adamantanes 157a,b.
Scheme 47: Synthesis of diaryl carbonates 160a–d from triarylmethanols 159a–d through successive oxygen insert...
Scheme 48: The synthesis of sesquiterpenes 162 from ketone 161 with a Criegee rearrangement as one key step.
Scheme 49: Synthesis of trans-hydrindan derivatives 164, 165.
Scheme 50: The Hock rearrangement.
Scheme 51: The general scheme of the cumene process.
Scheme 52: The Hock rearrangement of aliphatic hydroperoxides.
Scheme 53: The mechanism of solvolysis of brosylates 174a–c and spiro cyclopropyl carbinols 175a–c in THF/H2O2....
Scheme 54: The fragmentation mechanism of hydroperoxy acetals 178 to esters 179.
Scheme 55: The acid-catalyzed rearrangement of phenylcyclopentyl hydroperoxide 181.
Scheme 56: The peroxidation of tertiary alcohols in the presence of a catalytic amount of acid.
Scheme 57: The acid-catalyzed reaction of bicyclic secondary alcohols 192 with hydrogen peroxide.
Scheme 58: The photooxidation of 5,6-disubstituted 3,4-dihydro-2H-pyrans 196.
Scheme 59: The oxidation of tertiary alcohols 200a–g, 203a,b, and 206.
Scheme 60: Transformation of functional peroxide 209 leading to 2,3-disubstitued furans 210 in one step.
Scheme 61: The synthesis of carbazoles 213 via peroxide rearrangement.
Scheme 62: The construction of C–N bonds using the Hock rearrangement.
Scheme 63: The synthesis of moiety 218 from 217 which is a structural motif in the antitumor–antibiotic of CC-...
Scheme 64: The in vivo oxidation steps of cholesterol (219) by singlet oxygen.
Scheme 65: The proposed mechanism of the rearrangement of cholesterol-5α-OOH 220.
Scheme 66: Photochemical route to artemisinin via Hock rearrangement of 223.
Scheme 67: The Kornblum–DeLaMare rearrangement.
Scheme 68: Kornblum–DeLaMare transformation of 1-phenylethyl tert-butyl peroxide (225).
Scheme 69: The synthesis 4-hydroxyenones 230 from peroxide 229.
Scheme 70: The Kornblum–DeLaMare rearrangement of peroxide 232.
Scheme 71: The reduction of peroxide 234.
Scheme 72: The Kornblum–DeLaMare rearrangement of endoperoxide 236.
Scheme 73: The rearrangement of peroxide 238 under Kornblum–DeLaMare conditions.
Scheme 74: The proposed mechanism of rearrangement of peroxide 238.
Scheme 75: The Kornblum–DeLaMare rearrangement of peroxides 242a,b.
Scheme 76: The base-catalyzed rearrangements of bicyclic endoperoxides having electron-withdrawing substituent...
Scheme 77: The base-catalyzed rearrangements of bicyclic endoperoxides 249a,b having electron-donating substit...
Scheme 78: The base-catalyzed rearrangements of bridge-head substituted bicyclic endoperoxides 251a,b.
Scheme 79: The Kornblum–DeLaMare rearrangement of hydroperoxide 253.
Scheme 80: Synthesis of β-hydroxy hydroperoxide 254 from endoperoxide 253.
Scheme 81: The amine-catalyzed rearrangement of bicyclic endoperoxide 263.
Scheme 82: The base-catalyzed rearrangement of meso-endoperoxide 268 into 269.
Scheme 83: The photooxidation of 271 and subsequent Kornblum–DeLaMare reaction.
Scheme 84: The Kornblum–DeLaMare rearrangement as one step in the oxidation reaction of enamines.
Scheme 85: The Kornblum–DeLaMare rearrangement of 3,5-dihydro-1,2-dioxenes 284, 1,2-dioxanes 286, and tert-but...
Scheme 86: The Kornblum–DeLaMare rearrangement of epoxy dioxanes 290a–d.
Scheme 87: Rearrangement of prostaglandin H2 292.
Scheme 88: The synthesis of epicoccin G (297).
Scheme 89: The Kornblum–DeLaMare rearrangement used in the synthesis of phomactin A.
Scheme 90: The Kornblum–DeLaMare rearrangement in the synthesis of 3H-quinazolin-4-one 303.
Scheme 91: The Kornblum–DeLaMare rearrangement in the synthesis of dolabriferol (308).
Scheme 92: Sequential transformation of 3-substituted 2-pyridones 309 into 3-hydroxypyridine-2,6-diones 311 in...
Scheme 93: The Kornblum–DeLaMare rearrangement of peroxide 312 into hydroxy enone 313.
Scheme 94: The Kornblum–DeLaMare rearrangement in the synthesis of polyfunctionalized carbonyl compounds 317.
Scheme 95: The Kornblum–DeLaMare rearrangement in the synthesis of (Z)-β-perfluoroalkylenaminones 320.
Scheme 96: The Kornblum–DeLaMare rearrangement in the synthesis of γ-ketoester 322.
Scheme 97: The Kornblum–DeLaMare rearrangement in the synthesis of diterpenoids 326 and 328.
Scheme 98: The synthesis of natural products hainanolidol (331) and harringtonolide (332) from peroxide 329.
Scheme 99: The synthesis of trans-fused butyrolactones 339 and 340.
Scheme 100: The synthesis of leucosceptroid C (343) and leucosceptroid P (344) via the Kornblum–DeLaMare rearra...
Scheme 101: The Dakin oxidation of arylaldehydes or acetophenones.
Scheme 102: The mechanism of the Dakin oxidation.
Scheme 103: A solvent-free Dakin reaction of aromatic aldehydes 356.
Scheme 104: The organocatalytic Dakin oxidation of electron-rich arylaldehydes 358.
Scheme 105: The Dakin oxidation of electron-rich arylaldehydes 361.
Scheme 106: The Dakin oxidation of arylaldehydes 358 in water extract of banana (WEB).
Scheme 107: A one-pot approach towards indolo[2,1-b]quinazolines 364 from indole-3-carbaldehydes 363 through th...
Scheme 108: The synthesis of phenols 367a–c from benzaldehydes 366a-c via acid-catalyzed Dakin oxidation.
Scheme 109: Possible transformation paths of the highly polarized boric acid coordinated H2O2–aldehyde adduct 3...
Scheme 110: The Elbs oxidation of phenols 375 to hydroquinones.
Scheme 111: The mechanism of the Elbs persulfate oxidation of phenols 375 affording p-hydroquinones 376.
Scheme 112: Oxidation of 2-pyridones 380 under Elbs persulfate oxidation conditions.
Scheme 113: Synthesis of 3-hydroxy-4-pyridone (384) via an Elbs oxidation of 4-pyridone (382).
Scheme 114: The Schenck rearrangement.
Scheme 115: The Smith rearrangement.
Scheme 116: Three main pathways of the Schenck rearrangement.
Scheme 117: The isomerization of hydroperoxides 388 and 389.
Scheme 118: Trapping of dioxacyclopentyl radical 392 by oxygen.
Scheme 119: The hypothetical mechanism of the Schenck rearrangement of peroxide 394.
Scheme 120: The autoxidation of oleic acid (397) with the use of labeled isotope 18O2.
Scheme 121: The rearrangement of 18O-labeled hydroperoxide 400 under an atmosphere of 16O2.
Scheme 122: The rearrangement of the oleate-derived allylic hydroperoxides (S)-421 and (R)-425.
Scheme 123: Mechanisms of Schenck and Smith rearrangements.
Scheme 124: The rearrangement and cyclization of 433.
Scheme 125: The Wieland rearrangement.
Scheme 126: The rearrangement of bis(triphenylsilyl) 439 or bis(triphenylgermyl) 441 peroxides.
Scheme 127: The oxidative transformation of cyclic ketones.
Scheme 128: The hydroxylation of cyclohexene (447) in the presence of tungstic acid.
Scheme 129: The oxidation of cyclohexene (447) under the action of hydrogen peroxide.
Scheme 130: The reaction of butenylacetylacetone 455 with hydrogen peroxide.
Scheme 131: The oxidation of bridged 1,2,4,5-tetraoxanes.
Scheme 132: The proposed mechanism for the oxidation of bridged 1,2,4,5-tetraoxanes.
Scheme 133: The rearrangement of ozonides.
Scheme 134: The acid-catalyzed oxidative rearrangement of malondialdehydes 462 under the action of H2O2.
Scheme 135: Pathways of the Lewis acid-catalyzed cleavage of dialkyl peroxides 465 and ozonides 466.
Scheme 136: The mechanism of the transformation of (tert-butyldioxy)cyclohexanedienones 472.
Scheme 137: The synthesis of Vitamin K3 from 472a.
Scheme 138: Proposed mechanism for the transformation of 478d into silylated endoperoxide 479d.
Scheme 139: The rearrangement of hydroperoxide 485 to form diketone 486.
Scheme 140: The base-catalyzed rearrangement of cyclic peroxides 488a–g.
Scheme 141: Synthesis of chiral epoxides and aldols from peroxy hemiketals 491.
Scheme 142: The multistep transformation of (R)-carvone (494) to endoperoxides 496a–e.
Scheme 143: The decomposition of anthracene endoperoxide 499.
Scheme 144: Synthesis of esters 503 from aldehydes 501 via rearrangement of peroxides 502.
Scheme 145: Two possible paths for the base-promoted decomposition of α-azidoperoxides 502.
Scheme 146: The Story decomposition of cyclic diperoxide 506a.
Scheme 147: The Story decomposition of cyclic triperoxide 506b.
Scheme 148: The thermal rearrangement of endoperoxides A into diepoxides B.
Scheme 149: The transformation of peroxide 510 in the synthesis of stemolide (511).
Scheme 150: The possible mechanism of the rearrangement of endoperoxide 261g.
Scheme 151: The photooxidation of indene 517.
Scheme 152: The isomerization of ascaridole (523).
Scheme 153: The isomerization of peroxide 525.
Scheme 154: The thermal transformation of endoperoxide 355.
Scheme 155: The photooxidation of cyclopentadiene (529) at a temperature higher than 0 °C.
Scheme 156: The thermal rearrangement of endoperoxides 538a,b.
Scheme 157: The transformation of peroxides 541.
Scheme 158: The thermal rearrangements of strained cyclic peroxides.
Scheme 159: The thermal rearrangement of diacyl peroxide 551 in the synthesis of C4-epi-lomaiviticin B core 553....
Scheme 160: The 1O2 oxidation of tryptophan (554) and rearrangement of dioxetane intermediate 555.
Scheme 161: The Fe(II)-promoted cleavage of aryl-substituted bicyclic peroxides.
Scheme 162: The proposed mechanism of the Fe(II)-promoted rearrangement of 557a–c.
Scheme 163: The reaction of dioxolane 563 with Fe(II) sulfate.
Scheme 164: Fe(II)-promoted rearrangement of 1,2-dioxane 565.
Scheme 165: Fe(II) cysteinate-promoted rearrangement of 1,2-dioxolane 568.
Scheme 166: The transformation of 1,2-dioxanes 572a–c under the action of FeCl2.
Scheme 167: Fe(II) cysteinate-promoted transformation of tetraoxane 574.
Scheme 168: The CoTPP-catalyzed transformation of bicyclic endoperoxides 600a–d.
Scheme 169: The CoTPP-catalyzed transformation of epoxy-1,2-dioxanes.
Scheme 170: The Ru(II)-catalyzed reactions of 1,4-endoperoxide 261g.
Scheme 171: The Ru(II)-catalyzed transformation as a key step in the synthesis of elyiapyrone A (610) from 1,4-...
Scheme 172: Peroxides with antimalarial activity.
Scheme 173: The interaction of iron ions with artemisinin (616).
Scheme 174: The interaction of FeCl2 with 1,2-dioxanes 623, 624.
Scheme 175: The mechanism of reaction 623 and 624 with Fe(II)Cl2.
Scheme 176: The reaction of bicyclic natural endoperoxides G3-factors 631–633 with FeSO4.
Scheme 177: The transformation of terpene cardamom peroxide 639.
Scheme 178: The different ways of the cleavage of tetraoxane 643.
Scheme 179: The LC–MS analysis of interaction of tetraoxane 646 with iron(II)heme 647.
Scheme 180: The rearrangement of 3,6-epidioxy-1,10-bisaboladiene (EDBD, 649).
Scheme 181: Easily oxidized substrates.
Scheme 182: Biopathway of synthesis of prostaglandins.
Scheme 183: The reduction and rearrangements of isoprostanes.
Scheme 184: The partial mechanism for linoleate 658 oxidation.
Scheme 185: The transformation of lipid hydroperoxide.
Scheme 186: The acid-catalyzed cleavage of the product from free-radical oxidation of cholesterol (667).
Scheme 187: Two pathways of catechols oxidation.
Scheme 188: Criegee-like or Hock-like rearrangement of the intermediate hydroperoxide 675 in dioxygenase enzyme...
Scheme 189: Carotinoides 679 cleavage by carotenoid cleavage dioxygenases.
Methylpalladium complexes with pyrimidine-functionalized N-heterocyclic carbene ligands
- Dirk Meyer and
- Thomas Strassner
Beilstein J. Org. Chem. 2016, 12, 1557–1565, doi:10.3762/bjoc.12.150
- products while avoiding over-oxidation to carbon dioxide is still one of the most difficult tasks and considered to be one of the “Holy Grails” of chemistry [7]. Early work by Bergman [8][9] and Graham [10][11] showed that the activation of methane is possible, but their systems provided only
Graphical Abstract
Scheme 1: Synthesis of the monomethylpalladium(II) complexes 9–11 (in DCM) and 12 (in CH3CN).
Figure 1: Possible isomers.
Figure 2: ORTEP [39] style plot of complex 9 in the solid state. Thermal ellipsoids are given at the 50% probabil...
Figure 3: ORTEP [39] style plot of complex 12 in the solid state. Thermal ellipsoids are drawn at the 50% probabi...
Scheme 2: Synthesis of complex 13.
Figure 4: ORTEP [39] style plot of complex 13 in the solid state. Thermal ellipsoids are drawn at the 50% probabi...
Scheme 3: Possible pathways of methyl trifluoroacetate formation starting from complex 13.
Scheme 4: Synthesis of complex 14 by conversion of complex 13 with iodobenzene bistrifluoroacetate.
Scheme 5: Synthesis of the [((pym)^(NHC-R))PdII(CH3)2] complex 15.
