Search for "functionality" in Full Text gives 613 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Beilstein J. Org. Chem. 2024, 20, 3069–3076, doi:10.3762/bjoc.20.255
Graphical Abstract
Scheme 1: Metallotropic rearrangement and regioselectivity issues.
Scheme 2: Asymmetric catalytic allenylation of aldehydes.
Scheme 3: Selective preparation of propargyltrichlorosilane.
Scheme 4: Evaluation of C2-symmetric catalysts with benzaldehyde (1a) as a model aldehyde. Reaction condition...
Scheme 5: Evaluation of the extent to which (S)-8 catalyzed the allenylation reaction. Reaction conditions: a...
Figure 1: A potential energy surface (PES) for the proposed mechanism for (a) isomerization of propargyltrich...
Beilstein J. Org. Chem. 2024, 20, 2959–3006, doi:10.3762/bjoc.20.249
Graphical Abstract
Scheme 1: Organic peroxide initiators in polymer chemistry.
Scheme 2: Synthesis of organic peroxides.
Scheme 3: Richness of radical cascades with species formed from hydroperoxides in redox conditions.
Scheme 4: Co-catalyzed allylic peroxidation of alkenes 1 and 3 by TBHP.
Scheme 5: Allylic peroxidation of alkenes 6 by Pd(II)TBHP.
Scheme 6: Cu(I)-catalyzed allylic peroxidation.
Scheme 7: Enantioselective peroxidation of alkenes 10 with TBHP in the presence of copper(I) compounds.
Scheme 8: Oxidation of α-pinene (12) by the Cu(I)/TBHP system.
Scheme 9: Introduction of the tert-butylperoxy fragment into the α-position of cyclic ketones 15 and 17.
Scheme 10: α-Peroxidation of β-dicarbonyl compounds 19 using the Cu(II)/TBHP system.
Scheme 11: Co-catalyzed peroxidation of cyclic compounds 21 with TBHP.
Scheme 12: Co-, Mn- and Fe-catalyzed peroxidation of 2-oxoindoles 23, barbituric acids 25, and 4-hydroxycoumar...
Scheme 13: Cu-catalyzed and metal-free peroxidation of barbituric acid derivatives 31 and 3,4-dihydro-1,4-benz...
Scheme 14: Electrochemical peroxidation of 1,3-dicarbonyl compounds 35.
Scheme 15: Peroxidation of β-dicarbonyl compounds, cyanoacetic esters and malonic esters 37 by the TBAI/TBHP s...
Scheme 16: Cu-catalyzed peroxidation of malonodinitriles and cyanoacetic esters 39 with TBHP.
Scheme 17: Mn-catalyzed remote peroxidation via trifluromethylation of double bond.
Scheme 18: Cu-catalyzed remote peroxidation via trifluromethylthiolation of double bond.
Scheme 19: Fe-, Mn-, and Ru-catalyzed peroxidation of alkylaromatics 45, 47, 49, and 51 with TBHP.
Scheme 20: Cu-catalyzed peroxidation of diphenylacetonitrile (53) with TBHP.
Scheme 21: Cu-catalyzed peroxidation of benzyl cyanides 60 with TBHP.
Scheme 22: Synthesis of tert-butylperoxy esters 63 from benzyl alcohols 62 using the TBAI/TBHP system.
Scheme 23: Enantioselective peroxidation of 2-phenylbutane (64) with TBHP and chiral Cu(I) complex.
Scheme 24: Photochemical synthesis of peroxides 67 from carboxylic acids 66.
Scheme 25: Photochemical peroxidation of benzylic C(sp3)–H.
Scheme 26: Cu- and Ru-catalyzed peroxidation of alkylamines with TBHP.
Scheme 27: Peroxidation of amides 76 with the TBAI/TBHP system.
Scheme 28: Fe-catalyzed functionalization of ethers 78 with TBHP.
Scheme 29: Synthesis of 4-(tert-butylperoxy)-5-phenyloxazol-2(3H)-ones 82 from benzyl alcohols 80 and isocyana...
Scheme 30: Fe- and Co-catalyzed peroxidation of alkanes with TBHP.
Scheme 31: Rh-catalyzed tert-butylperoxy dienone synthesis with TBHP.
Scheme 32: Rh- and Cu-catalyzed phenolic oxidation with TBHP.
Scheme 33: Metal-free peroxidation of phenols 94.
Scheme 34: Cu-catalyzed alkylation–peroxidation of acrylonitrile.
Scheme 35: Cu-catalyzed cycloalkylation–peroxidation of coumarins 99.
Scheme 36: Metal-free cycloalkylation–peroxidation of coumarins 102.
Scheme 37: Difunctionalization of indene 104 with tert-butylperoxy and alkyl groups.
Scheme 38: Acid-catalyzed radical addition of ketones (108, 111) and TBHP to alkenes 107 and acrylates 110.
Scheme 39: Cu-catalyzed alkylation–peroxidation of alkenes 113 with TBHP and diazo compounds 114.
Scheme 40: Cobalt(II)-catalyzed addition of TBHP and 1,3-dicarbonyl compound 116 to alkenes 117.
Scheme 41: Cu(0)- or Co(II)-catalyzed addition of TBHP and alcohols 120 to alkenes 119.
Scheme 42: Fe-catalyzed functionalization of allenes 122 with TBHP.
Scheme 43: Fe-catalyzed alkylation–peroxidation of alkenes 125 and 127.
Scheme 44: Fe- and Co-catalyzed alkylation–peroxidation of alkenes 130, 133 and 134 with TBHP and aldehydes as...
Scheme 45: Carbonylation–peroxidation of alkenes 137, 140, 143 with hydroperoxides and aldehydes.
Scheme 46: Carbamoylation–peroxidation of alkenes 146 with formamides and TBHP.
Scheme 47: TBAB-catalyzed carbonylation–peroxidation of alkenes.
Scheme 48: VOCl2-catalyzed carbonylation–peroxidation of alkenes 152.
Scheme 49: Acylation–peroxidation of alkenes 155 with aldehydes 156 and TBHP using photocatalysis.
Scheme 50: Cu-catalyzed peroxidation of styrenes 158.
Scheme 51: Fe-catalyzed acylation-peroxidation of alkenes 161 with carbazates 160 and TBHP.
Scheme 52: Difunctionalization of alkenes 163, 166 with TBHP and (per)fluoroalkyl halides.
Scheme 53: Difunctionalization of alkenes 169 and 172 with hydroperoxides and sodium (per)fluoromethyl sulfina...
Scheme 54: Trifluoromethylation–peroxidation of styrenes 175 using MOF Cu3(BTC)2 as a catalyst.
Scheme 55: Difunctionalization of alkenes 178 with tert-butylperoxy and dihalomethyl fragments.
Scheme 56: Difunctionalization of alkenes 180 with the tert-butylperoxy and dihalomethyl moieties.
Scheme 57: The nitration–peroxidation of alkenes 182 with t-BuONO and TBHP.
Scheme 58: Azidation–peroxidation of alkenes 184 with TMSN3 and TBHP.
Scheme 59: Co-catalyzed bisperoxidation of butadiene 186.
Scheme 60: Bisperoxidation of styrene (189) and acrylonitrile (192) with TBHP by Minisci.
Scheme 61: Mn-catalyzed synthesis of bis(tert-butyl)peroxides 195 from styrenes 194.
Scheme 62: Bisperoxidation of arylidene-9H-fluorenes 196 and 3-arylidene-2-oxoindoles 198 with TBHP under Mn-c...
Scheme 63: Synthesis of bisperoxides from styrenes 200 and 203 using the Ru and Rh catalysis.
Scheme 64: Iodine-catalyzed bisperoxidation of styrenes 206.
Scheme 65: Synthesis of di-tert-butylperoxyoxoindoles 210 from acrylic acid anilides 209 using a Pd(II)/TBHP o...
Scheme 66: Pinolation/peroxidation of styrenes 211 catalyzed by Cu(I).
Scheme 67: TBAI-catalyzed acyloxylation–peroxidation of alkenes 214 with carboxylic acids and TBHP.
Scheme 68: Difunctionalization of alkenes 217 with TBHP and water or alcohols.
Scheme 69: TBAI-catalyzed hydroxyperoxidation of 1,3-dienes 220.
Scheme 70: Hydroxyperoxidation of 1,3-dienes 220.
Scheme 71: Iodination/peroxidation of alkenes 223 with I2 and hydroperoxides.
Scheme 72: The reactions of cyclic enol ethers 226 and 228 with I2/ROOH system.
Scheme 73: Synthesis of 1-(tert-butylperoxy)-2-iodoethanes 231.
Scheme 74: Synthesis of 1-iodo-2-(tert-butylperoxy)ethanes 233.
Scheme 75: Cu-catalyzed phosphorylation–peroxidation of alkenes 234.
Scheme 76: Co-catalyzed phosphorylation–peroxidation of alkenes 237.
Scheme 77: Ag-catalyzed sulfonylation–peroxidation of alkenes 241.
Scheme 78: Co-catalyzed sulfonylation–peroxidation of alkenes 244.
Scheme 79: Synthesis of α/β-peroxysulfides 248 and 249 from styrenes 247.
Scheme 80: Cu-catalyzed trifluoromethylthiolation–peroxidation of alkenes 250 and allenes 252.
Scheme 81: Photocatalytic sulfonyl peroxidation of alkenes 254 via deamination of N-sulfonyl ketimines 255.
Scheme 82: Photoredox-catalyzed 1,4-peroxidation–sulfonylation of enynones 257.
Scheme 83: Cu-catalyzed silylperoxidation of α,β-unsaturated compounds 260 and enynes 261.
Scheme 84: Fe-catalyzed silyl peroxidation of alkenes.
Scheme 85: Cu-catalyzed germyl peroxidation of alkenes 267.
Scheme 86: TBAI-catalyzed intramolecular cyclization of diazo compounds 269 with further peroxidation.
Scheme 87: Co-catalyzed three-component coupling of benzamides 271, diazo compounds 272 and TBHP.
Scheme 88: Co-catalyzed esterification-peroxidation of diazo compounds 274 with TBHP and carboxylic acids 275.
Scheme 89: Cu-catalyzed alkylation–peroxidation of α-carbonylimines 277 or ketones 280.
Scheme 90: Mn-catalyzed ring-opening peroxidation of cyclobutanols 282 with TBHP.
Scheme 91: Peroxycyclization of tryptamines 284 with TBHP.
Scheme 92: Radical cyclization–peroxidation of homotryptamines 287.
Scheme 93: Iodine-catalyzed oxidative coupling of indoles 288, cyanoacetic esters and TBHP.
Scheme 94: Summary of metal-catalyzed peroxidation processes.
Beilstein J. Org. Chem. 2024, 20, 2931–2939, doi:10.3762/bjoc.20.245
Graphical Abstract
Figure 1: Structure and stability of hypervalent iodine compounds.
Figure 2: Phosphorus-iodonium ylids investigated in this study: Yields (for synthetic procedures, see Supporting Information File 1), stru...
Figure 3: (a) Selected TGA thermograms of phosphorus-iodonium ylids at 10 °C min−1 in N2 (full dataset in Supporting Information File 1). ...
Figure 4: (a) Proposed decomposition mechanism based on ex situ analysis (1H, 31P NMR, ESI-MS) following abor...
Beilstein J. Org. Chem. 2024, 20, 2921–2930, doi:10.3762/bjoc.20.244
Graphical Abstract
Figure 1: Chemical structures of violanthrone and dihydroxyviolanthrone.
Figure 2: Chemical structures of 2b and 3b.
Scheme 1: Synthesis of compounds 2a–c and 3a–c.
Figure 3: Optimised ground state geometries of compounds 2 and 3 calculated using B3LYP/6-311G(d,p) in the ga...
Figure 4: Views of the crystal structure of 3b (left, shows displacement ellipsoids drawn at 50% probability ...
Figure 5: Absorption spectra of 3a–c measured in dichloromethane solution (1 × 10−5 M).
Figure 6: SWV (left) and CV (right) of compound 3a–c (in dichloromethane 1 × 10−3 M) (V vs Fc/Fc+).
Beilstein J. Org. Chem. 2024, 20, 2818–2826, doi:10.3762/bjoc.20.237
Graphical Abstract
Figure 1: Previously reported lanthanide complexes [12,16,17].
Scheme 1: Synthesis of Tb.1.
Figure 2: Absorption (red line), excitation (yellow line, λem = 615 nm), and emission (green line, λex = 250 ...
Figure 3: (a) Changes in the luminescence emission spectrum of 5 µM [Tb.1·3Cu]3+ upon the addition of Na2S (0...
Figure 4: (a) Changes in the luminescence emission spectrum of 5 µM [Tb.1·3Cu]3+ upon the addition of Na2S (0...
Figure 5: Luminescence intensity of 5 μM Tb.1 in 10 mM Tris-HCl buffer, pH 7.4, containing 5% DMSO upon the a...
Figure 6: Changes in luminescent intensity of [Tb.1·3Cu]3+ (5 µM) detected at 545 nm in the presence of vario...
Figure 7: Chemical structure and mode of action of [Tb(DPA-N3)3]3− for detection of H2S(g) [11].
Beilstein J. Org. Chem. 2024, 20, 2608–2634, doi:10.3762/bjoc.20.220
Graphical Abstract
Figure 1: Hierarchical assembly occurring across length scales. Molecular interactions result in fibres which...
Figure 2: Three-dimensional CLSM image of a multicomponent supramolecular structure. The three-dimensional CL...
Figure 3: AFM images of air-dried aqueous Fmoc-FF, Fmoc-S, and 1:1 Fmoc-FF:Fmoc-S solutions. Figure 3 was reprinted f...
Figure 4: (a) 3D CLSM images of macroscopically a self-sorting gel network, where all fibres were stained gre...
Figure 5: (a) 3D AFM topographic image of dried elastin fibre. (b) Indicative height and diameter profile plo...
Figure 6: The nano-to-micro imaging range of SEM and TEM [30]. Cartoons represent the nanoparticles, pores, nanow...
Figure 7: Cartoon of artifacts caused by blotting and thinning. a) Alignment of threadlike micelles (left) [32] a...
Figure 8: (a) Chemical structures of monomer compounds and a schematic of the resulting chiral helical struct...
Figure 9: Commonly observed entanglements of urea-based supramolecular helices. (a) Double helix, (b) quadrup...
Figure 10: (a) SEM image of a single three-stranded braid showing a defect in which the braid separates into s...
Figure 11: Visualization of individual atoms at 1.25 Å resolution. Three apoferritin residues are shown at hig...
Figure 12: Cartoon of a general small-angle scattering setup.
Figure 13: (a) SAXS data and fits for solution in H2O (open symbols) and D2O (closed symbols). Cryo-TEM data f...
Figure 14: (a) A cartoon illustrating the orientation phases caused by shear alignment of WLMs. (b) Rheologica...
Figure 15: (a) Chemical structure of 2NapFF and (b) a cartoon cross-section of the hollow cylinder structure f...
Figure 16: Length scales of scattering and imaging techniques [16,54,55].
Figure 17: A schematic of a hydrogel network showing the significance of various parameters extracted from SAN...
Figure 18: The morphologies of a co-assembled complex dependent on the solvent composition. Figure 18 is from [89] and was ...
Figure 19: Allowed and forbidden crossings of entangled helices. Figure 19 is from [44] and was adapted by permission from ...
Figure 20: (a) Cryo-TEM density map of self-assembled (ʟ,ʟ)-2NapFF. (b) Computational model fit to cryo-TEM ma...
Figure 21: Map showing an incomplete list of global scientific centres providing access to (a) cryo-EM in red ...
Figure 22: SANS at a range of times. Solid lines are fits to a hollow cylinder model (T = 114 min and T = 202 ...
Figure 23: SAXS data of 5 mg/mL alanine-functionalised perylene bisimide (PBI-A) in 20 v/v % MeOH at pH (a) 2;...
Figure 24: Cryo-TEM sample prepared using plunge freezing in liquid nitrogen slush and sublimed for 30 minutes...
Beilstein J. Org. Chem. 2024, 20, 2349–2377, doi:10.3762/bjoc.20.201
Graphical Abstract
Scheme 1: The position of homoallylic amines in the landscape of alkaloid and nitrogen compounds syntheses.
Scheme 2: 3,3’-Diaryl-BINOL-catalysed asymmetric organocatalytic allylation of acylimines [24].
Scheme 3: Aminophenol-catalysed reaction between N-phosphinoylimines and pinacol allylboronic ester. Imine sc...
Scheme 4: Asymmetric geranylation and prenylation of indoles catalysed by (R)- or (S)-3,3’-dibromo-BINOL [25]. aA...
Scheme 5: (R)-3,3’-Di(3,5-di(trifluoromethyl)phenyl-BINOL-catalysed asymmetric geranylation and prenylation o...
Scheme 6: Microwave-induced one-pot asymmetric allylation of in situ-formed arylimines, catalysed by (R)-3,3’...
Scheme 7: Microwave-induced one-pot asymmetric allylation of in situ-formed arylimines, catalysed by (R)-3,3’...
Scheme 8: Kinetic resolution of chiral secondary allylboronates [15,30].
Scheme 9: (E)-Stereospecific asymmetric α-trifluoromethylallylation of cyclic imines and hydrazones [31].
Scheme 10: Hosomi–Sakurai-type allylation of in situ-formed N-Fmoc aldimines [32].
Figure 1: Two different pathways for the Hosomi–Sakurai reaction of allyltrimethylsilane with N-Fmoc aldimine...
Scheme 11: Chiral squaramide-catalysed hydrogen bond-assisted chloride abstraction–allylation of N-carbamoyl α...
Figure 2: The pyrrolidine unit gem-methyl group conformational control in the squaramide-based catalyst [34].
Figure 3: The energetic difference between the transition states of the two proposed modes of the reaction (SN...
Scheme 12: One-pot preparation procedure for oxazaborolidinium ion (COBI) 63 [37].
Scheme 13: Chiral oxazaborolidinium ion (COBI)-catalysed allylation of N-(2-hydroxy)phenylimines with allyltri...
Scheme 14: The two-step N-(2-hydroxy)phenyl group deprotection procedure [37].
Scheme 15: Low-temperature (−40 °C) NMR experiments evidencing the reversible formation of the active COBI–imi...
Figure 4: Two computed reaction pathways for the COBI-catalysed Strecker reaction (TS1 identical to allylatio...
Scheme 16: Highly chemoselective and stereospecific synthesis of γ- and γ,δ-substituted homoallylic amines by ...
Scheme 17: Catalytic cycle for the three-component allylation with HBD/πAr–Ar catalyst [39].
Scheme 18: Reactivity of model electrophiles [39].
Scheme 19: HBD/πAr–Ar catalyst rational design and optimisation [39].
Scheme 20: Scope of the three-component HBD/πAr–Ar-catalysed reaction [39].
Scheme 21: Limitations of the HBD/πAr–Ar-catalysed reaction [39].
Scheme 22: Asymmetric chloride-directed dearomative allylation of in situ-generated N-acylquinolinium ions, ca...
Scheme 23: Chiral phosphoric acid-catalysed aza-Cope rearrangement of in situ-formed N-α,α’-diphenyl-(α’’-ally...
Scheme 24: Tandem (R)-VANOL-triborate-catalysed asymmetric aza-Cope rearrangement of in situ-formed aldimines ...
Scheme 25: (S)-TRIP-catalysed enantioconvergent aza-Cope rearrangement of β-formyl amides, substrate scope [43]. a...
Scheme 26: (S)-TRIP-catalysed enantioconvergent aza-Cope rearrangement of β-formyl amides 16–19, amide and all...
Scheme 27: Synthetic applications of homoallylic N-benzophenone imine products 131 [43].
Scheme 28: Chiral organocatalysed addition of 2,2,2-trifluoroethyl ketimines to isatin-derived Morita–Baylis–H...
Scheme 29: Chiral chinchona-derived amine-catalysed reaction between isatin-based Morita–Baylis–Hilman carbona...
Scheme 30: (R)-VAPOL-catalysed hydrogen atom transfer deracemisation [45].
Scheme 31: Chiral PA-catalysed [1,3]-rearrangement of ene-aldimines [46].
Beilstein J. Org. Chem. 2024, 20, 2342–2348, doi:10.3762/bjoc.20.200
Graphical Abstract
Figure 1: Examples of bioactive compounds containing the 1,2,3-triazin-4-one core.
Scheme 1: Tandem diazotization/azo coupling reactions of (1,2,5-oxadiazolyl)carboxamides containing an amino ...
Scheme 2: Synthesis of target furoxanotriazinones 1a–h.
Scheme 3: The synthesis of furazanotriazinones 7a–h.
Figure 2: The X-ray structure of compound 1b (CCDC 2363621) and 7h (CCDC 2363622).
Scheme 4: Control experiment with Na15NO2.
Figure 3: NO release data.
Beilstein J. Org. Chem. 2024, 20, 2208–2216, doi:10.3762/bjoc.20.188
Graphical Abstract
Figure 1: The meta-hetarylaniline motif in bioactive molecules.
Scheme 1: Strategies to access meta-substituted anilines.
Figure 2: The model series of synthesized 1,3-diketones and corresponding calculated Hammett constants of het...
Scheme 2: Synthesis of meta-substituted anilines from 1,2,4-oxadiazol-5-yl substituted 1,3-diketone 1a. Condi...
Scheme 3: Synthesis of meta-substituted anilines from 1,3,4-oxadiazol-substituted 1,3-diketone 1b. Conditions...
Scheme 4: Synthesis of meta-substituted anilines from benzothiazol-2-yl and oxazol-2-yl-substituted 1,3-diket...
Scheme 5: Synthesis of meta-substituted aniline from isoxazol-3-yl-substituted 1,3-diketone 1e. Conditions B: ...
Figure 3: Scope of functionalized amines in three-component condensation. Conditions A: 1a,b,h,i (0.2–0.5 mmo...
Scheme 6: Proposed mechanism for the formation of meta-substituted anilines 3 via three-component benzannulat...
Beilstein J. Org. Chem. 2024, 20, 2084–2107, doi:10.3762/bjoc.20.180
Graphical Abstract
Figure 1: Carbohydrate conformational variability. a) Illustration of Φ, Ψ and ω dihedral angles for a repres...
Figure 2: Monosaccharides diversity in eukaryotes and bacteria. a) Eukaryotic monosaccharides. b) Examples of...
Figure 3: Different glycan representations. The 3’-sialyllactosamine is depicted according to the a) IUPAC no...
Figure 4: Visualisation programs. Different representation of a protein–ligand complex by using the most used...
Figure 5: A schematic representation of useful computational methods to study protein–glycan interactions. a)...
Beilstein J. Org. Chem. 2024, 20, 2024–2077, doi:10.3762/bjoc.20.178
Graphical Abstract
Scheme 1: Consecutive three-component synthesis of pyrazoles 1 via in situ-formed 1,3-diketones 2 [44].
Scheme 2: Consecutive three-component synthesis of 4-ethoxycarbonylpyrazoles 5 via SmCl3-catalyzed acylation ...
Scheme 3: Consecutive four-component synthesis of 1-(thiazol-2-yl)pyrazole-3-carboxylates 8 [51].
Scheme 4: Three-component synthesis of thiazolylpyrazoles 17 via in situ formation of acetoacetylcoumarins 18 ...
Scheme 5: Consecutive pseudo-four-component and four-component synthesis of pyrazoles 21 from sodium acetylac...
Scheme 6: Consecutive three-component synthesis of 1-substituted pyrazoles 24 from boronic acids, di(Boc)diim...
Scheme 7: Consecutive three-component synthesis of N-arylpyrazoles 25 via in situ formation of aryl-di(Boc)hy...
Scheme 8: Consecutive three-component synthesis of 1,3,4-substituted pyrazoles 27 and 28 from methylhydrazine...
Scheme 9: Consecutive three-component synthesis of 4-allylpyrazoles 32 via oxidative allylation of 1,3-dicarb...
Scheme 10: Pseudo-five-component synthesis of tris(pyrazolyl)methanes 35 [61].
Scheme 11: Pseudo-three-component synthesis of 5-(indol-3-yl)pyrazoles 39 from 1,3,5-triketones 38 [64].
Scheme 12: Three-component synthesis of thiazolylpyrazoles 43 [65].
Scheme 13: Three-component synthesis of triazolo[3,4-b]-1,3,4-thiadiazin-3-yl substituted 5-aminopyrazoles 47 [67]....
Scheme 14: Consecutive three-component synthesis of 5-aminopyrazoles 49 via formation of β-oxothioamides 50 [68].
Scheme 15: Synthesis of 3,4-biarylpyrazoles 52 from aryl halides, α-bromocinnamaldehyde, and tosylhydrazine vi...
Scheme 16: Consecutive three-component synthesis of 3,4-substituted pyrazoles 57 from iodochromones 55 by Suzu...
Scheme 17: Pseudo-four-component synthesis of pyrazolyl-2-pyrazolines 59 by ring opening/ring closing cyclocon...
Scheme 18: Consecutive three-component synthesis of pyrazoles 61 [77].
Scheme 19: Three-component synthesis of pyrazoles 62 from malononitrile, aldehydes, and hydrazines [78-90].
Scheme 20: Four-component synthesis of pyrano[2,3-c]pyrazoles 63 [91].
Scheme 21: Three-component synthesis of persubstituted pyrazoles 65 from aldehydes, β-ketoesters, and hydrazin...
Scheme 22: Three-component synthesis of pyrazol-4-carbodithioates 67 [100].
Scheme 23: Regioselective three-component synthesis of persubstituted pyrazoles 68 catalyzed by ionic liquid [...
Scheme 24: Consecutive three-component synthesis of 4-halopyrazoles 69 and anellated pyrazoles 70 [102].
Scheme 25: Three-component synthesis of 2,2,2-trifluoroethyl pyrazole-5-carboxylates 72 [103].
Scheme 26: Synthesis of pyrazoles 75 in a one-pot process via carbonylative Heck coupling and subsequent cycli...
Scheme 27: Copper-catalyzed three-component synthesis of 1,3-substituted pyrazoles 76 [105].
Scheme 28: Pseudo-three-component synthesis of bis(pyrazolyl)methanes 78 by ring opening-ring closing cyclocon...
Scheme 29: Three-component synthesis of 1,4,5-substituted pyrazoles 80 [107].
Scheme 30: Consecutive three-component synthesis of 3,5-bis(fluoroalkyl)pyrazoles 83 [111].
Scheme 31: Consecutive three-component synthesis of difluoromethanesulfonyl-functionalized pyrazole 88 [114].
Scheme 32: Consecutive three-component synthesis of perfluoroalkyl-substituted fluoropyrazoles 91 [115].
Scheme 33: Regioselective consecutive three-component synthesis of 1,3,5-substituted pyrazoles 93 [116].
Scheme 34: Three-component synthesis of pyrazoles 96 mediated by trimethyl phosphite [117].
Scheme 35: One-pot synthesis of pyrazoles 99 via Liebeskind–Srogl cross-coupling/cyclocondensation [118].
Scheme 36: Synthesis of 1,3,5-substituted pyrazoles 101 via domino condensation/Suzuki–Miyaura cross-coupling ...
Scheme 37: Consecutive three-component synthesis of 1,3,5-trisubstituted pyrazoles 102 and 103 by Sonogashira ...
Scheme 38: Polymer analogous consecutive three-component synthesis of pyrazole-based polymers 107 [132].
Scheme 39: Synthesis of 1,3,5-substituted pyrazoles 108 by sequentially Pd-catalyzed Kumada–Sonogashira cycloc...
Scheme 40: Consecutive four-step one-pot synthesis of 1,3,4,5-substituted pyrazoles 110 [137].
Scheme 41: Four-component synthesis of pyrazoles 113, 115, and 117 via Sonogashira coupling and subsequent Suz...
Scheme 42: Consecutive four- or five-component synthesis for the preparation of 4-pyrazoly-1,2,3-triazoles 119...
Scheme 43: Four-component synthesis of pyrazoles 121 via alkynone formation by carbonylative Pd-catalyzed coup...
Scheme 44: Preparation of 3-azulenyl pyrazoles 124 by glyoxylation, decarbonylative Sonogashira coupling, and ...
Scheme 45: Four-component synthesis of a 3-indoloylpyrazole 128 [147].
Scheme 46: Two-step synthesis of 5-acylpyrazoles 132 via glyoxylation-Stephen–Castro sequence and subsequent c...
Scheme 47: Copper on iron mediated consecutive three-component synthesis of 3,5-substituted pyrazoles 136 [150].
Scheme 48: Consecutive three-component synthesis of 3-substituted pyrazoles 141 by Sonogashira coupling and su...
Scheme 49: Consecutive three-component synthesis of pyrazoles 143 initiated by Cu(I)-catalyzed carboxylation o...
Scheme 50: Consecutive three-component synthesis of benzamide-substituted pyrazoles 146 starting from N-phthal...
Scheme 51: Consecutive three-component synthesis of 1,3,5-substituted pyrazoles 148 [156].
Scheme 52: Three-component synthesis of 4-ninhydrin-substituted pyrazoles 151 [158].
Scheme 53: Consecutive four-component synthesis of 4-(oxoindol)-1-phenylpyrazole-3-carboxylates 155 [159].
Scheme 54: Three-component synthesis of pyrazoles 160 [160].
Scheme 55: Consecutive three-component synthesis of pyrazoles 165 [162].
Scheme 56: Consecutive three-component synthesis of 3,5-disubstituted and 3-substituted pyrazoles 168 and 169 ...
Scheme 57: Three-component synthesis of 3,4,5-substituted pyrazoles 171 via 1,3-dipolar cycloaddition of vinyl...
Scheme 58: Three-component synthesis of pyrazoles 173 and 174 from aldehydes, tosylhydrazine, and vinylidene c...
Scheme 59: Three-component synthesis of pyrazoles 175 from glyoxyl hydrates, tosylhydrazine, and electron-defi...
Scheme 60: Pseudo-four-component synthesis of pyrazoles 177 from glyoxyl hydrates, tosylhydrazine, and aldehyd...
Scheme 61: Consecutive three-component synthesis of pyrazoles 179 via Knoevenagel-cycloaddition sequence [179].
Scheme 62: Three-component synthesis of 5-dimethylphosphonate substituted pyrazoles 182 from aldehydes, the Be...
Scheme 63: Consecutive three-component synthesis of 5-(dimethyl phosphonate)-substituted pyrazoles 185 from al...
Scheme 64: Three-component synthesis of 5-(dimethyl phosphonate)-substituted pyrazoles 187 from aldehydes, the...
Scheme 65: Three-component synthesis of 5-diethylphosphonate/5-phenylsulfonyl substituted pyrazoles 189 from a...
Scheme 66: Pseudo-three-component synthesis of 3-(dimethyl phosphonate)-substituted pyrazoles 190 [185].
Scheme 67: Three-component synthesis of 3-trifluoromethylpyrazoles 193 [186].
Scheme 68: Consecutive three-component synthesis of 5-stannyl-substituted 4-fluoropyrazole 197 [191,192].
Scheme 69: Pseudo-three-component synthesis of 3,5-diacyl-4-arylpyrazoles 199 [195].
Scheme 70: Three-component synthesis of pyrazoles 204 via nitrilimines [196].
Scheme 71: Three-component synthesis of 1,3,5-substituted pyrazoles 206 via formation of nitrilimines and sali...
Scheme 72: Pseudo four-component synthesis of pyrazoles 209 from acetylene dicarboxylates 147, hydrazonyl chlo...
Scheme 73: Consecutive three-component synthesis of pyrazoles 213 via syndnones 214 [200].
Scheme 74: Consecutive three-component synthesis of pyrazoles 216 via in situ-formed diazomethinimines 217 [201].
Scheme 75: Consecutive three-component synthesis of 3-methylthiopyrazoles 219 from aldehydes, hydrazine, and 1...
Scheme 76: Three-component synthesis of 1,3,5-substituted pyrazoles 220 from aldehydes, hydrazines, and termin...
Scheme 77: Three-component synthesis of 1,3,4,5-substituted pyrazoles 222 from aldehydes, hydrazines, and DMAD ...
Scheme 78: Pseudo three-component synthesis of pyrazoles 224 from sulfonyl hydrazone and benzyl acrylate under...
Scheme 79: Titanium-catalyzed consecutive four-component synthesis of pyrazoles 225 via enamino imines 226 [211]. a...
Scheme 80: Titanium-catalyzed three-component synthesis of pyrazoles 227 via enhydrazino imine complex interme...
Scheme 81: Pseudo-three-component synthesis of pyrazoles 229 via Glaser coupling of terminal alkynes and photo...
Scheme 82: Copper(II)acetate-mediated three-component synthesis of pyrazoles 232 [216].
Scheme 83: Copper-catalyzed three-component synthesis of 1,3,4-substituted pyrazole 234 from oxime acetates, a...
Scheme 84: Three-component synthesis of 3-trifluoroethylpyrazoles 239 [218].
Scheme 85: Pseudo-three-component synthesis of 1,4-bisulfonyl-substituted pyrazoles 242 [219].
Scheme 86: Three-component synthesis of 4-hydroxypyrazole 246 [221].
Beilstein J. Org. Chem. 2024, 20, 1839–1879, doi:10.3762/bjoc.20.162
Graphical Abstract
Scheme 1: Mechanism of the GBB reaction.
Scheme 2: Comparison of the performance of Sc(OTf)3 with some RE(OTf)3 in a model GBB reaction. Conditions: a...
Scheme 3: Comparison of the performance of various Brønsted acid catalysts in the synthesis of GBB adduct 6. ...
Scheme 4: Synthesis of Brønsted acidic ionic liquid catalyst 7. Conditions: a) neat, 60 °C, 24 h; b) TfOH, DC...
Scheme 5: Aryliodonium derivatives as organic catalysts in the GBB reaction. In the box the proposed binding ...
Scheme 6: DNA-encoded GBB reaction in micelles made of amphiphilic polymer 13. Conditions: a) 13 (50 equiv), ...
Scheme 7: GBB reaction catalyzed by cyclodextrin derivative 14. Conditions: a) 14 (1 mol %), water, 100 °C, 4...
Scheme 8: Proposed mode of activation of CALB. a) activation of the substrates; b) activation of the imine; c...
Scheme 9: One-pot GBB reaction–Suzuki coupling with a bifunctional hybrid biocatalyst. Conditions: a) Pd(0)-C...
Scheme 10: GBB reaction employing 5-HMF (23) as carbonyl component. Conditions: a) TFA (20 mol %), EtOH, 60 °C...
Scheme 11: GBB reaction with β-C-glucopyranosyl aldehyde 26. Conditions: a) InCl3 (20 mol %), MeOH, 70 °C, 2–3...
Scheme 12: GBB reaction with diacetylated 5-formyldeoxyuridine 29, followed by deacetylation of GBB adduct 30....
Scheme 13: GBB reaction with glycal aldehydes 32. Conditions: a) HFIP, 25 °C, 2–4 h.
Scheme 14: Vilsmeier–Haack formylation of 6-β-acetoxyvouacapane (34) and subsequent GBB reaction. Conditions: ...
Scheme 15: GBB reaction of 4-formlyl-PCP 37. Conditions: a) HOAc or HClO4, MeOH/DCM (2:3), rt, 3 d.
Scheme 16: GBB reaction with HexT-aldehyde 39. Conditions: a) 39 (20 nmol) and amidine (20 μmol), MeOH, rt, 6 ...
Scheme 17: GBB reaction of 2,4-diaminopirimidine 41. Conditions: a) Sc(OTf)3 (20 mol %), MeCN, 120 °C (MW), 1 ...
Scheme 18: Synthesis of N-edited guanine derivatives from 3,6-diamine-1,2,4-triazin-5-one 44. Conditions: a) S...
Scheme 19: Synthesis of 2-aminoimidazoles 49 by a Mannich-3CR followed by a one-pot intramolecular oxidative a...
Scheme 20: On DNA Suzuki–Miyaura reaction followed by GBB reaction. Conditions: a) CsOH, sSPhos-Pd-G2; b) AcOH...
Scheme 21: One-pot cascade synthesis of 5-iminoimidazoles. Conditions: a) Na2SO4, DMF, 220 °C (MW).
Scheme 22: GBB reaction of 5-amino-1H-imidazole-4-carbonile 57. Conditions: a) HClO4 (5 mol %), MeOH, rt, 24 h....
Scheme 23: One-pot cascade synthesis of indole-imidazo[1,2,a]pyridine hybrids. In blue the structural motif in...
Scheme 24: One-pot cascade synthesis of fused polycyclic indoles 67 or 69 from indole-3-carbaldehyde. Conditio...
Scheme 25: One-pot cascade synthesis of linked- and bridged polycyclic indoles from indole-2-carbaldehyde (70)...
Scheme 26: One-pot cascade synthesis of pentacyclic dihydroisoquinolines (X = N or CH). In blue the structural...
Scheme 27: One-pot stepwise synthesis of imidazopyridine-fused benzodiazepines 85. Conditions: a) p-TsOH (20 m...
Scheme 28: One-pot stepwise synthesis of benzoxazepinium-fused imidazothiazoles 89. Conditions: a) Yb(OTf)3 (2...
Scheme 29: One-pot stepwise synthesis of fused imidazo[4,5,b]pyridines 95. Conditions: a) HClO4, MeOH, rt, ove...
Scheme 30: Synthesis of heterocyclic polymers via the GBB reaction. Conditions: a) p-TsOH, EtOH, 70 °C, 24 h.
Scheme 31: One-pot multicomponent reaction towards the synthesis of covalent organic frameworks via the GBB re...
Scheme 32: One-pot multicomponent reaction towards the synthesis of covalent organic frameworks via the GBB re...
Scheme 33: GBB-like multicomponent reaction towards the synthesis of benzothiazolpyrroles (X = S) and benzoxaz...
Scheme 34: GBB-like multicomponent reaction towards the formation of imidazo[1,2,a]pyridines. Conditions: a) I2...
Scheme 35: Post-functionalization of GBB products via Ugi reaction. Conditions a) HClO4, DMF, rt, 24 h; b) MeO...
Scheme 36: Post-functionalization of GBB products via Click reaction. Conditions: a) solvent-free, 150 °C, 24 ...
Scheme 37: Post-functionalization of GBB products via cascade alkyne–allene isomerization–intramolecular nucle...
Scheme 38: Post-functionalization of GBB products via metal-catalyzed intramolecular N-arylation. In red and b...
Scheme 39: Post-functionalization of GBB products via isocyanide insertion (X = N or CH). Conditions: a) HClO4...
Scheme 40: Post-functionalization of GBB products via intramolecular nucleophilic addition to nitriles. Condit...
Scheme 41: Post-functionalization of GBB products via Pictet–Spengler cyclization. Conditions: a) 4 N HCl/diox...
Scheme 42: Post-functionalization of GBB products via O-alkylation. Conditions: a) TFA (20 mol %), EtOH, 120 °...
Scheme 43: Post-functionalization of GBB products via macrocyclization (X = -CH2CH2O-, -CH2-, -(CH2)4-). Condi...
Figure 1: Antibacterial activity of GBB-Ugi adducts 113 on both Gram-negative and Gram-positive strains.
Scheme 44: GBB multicomponent reaction using trimethoprim as the precursor. Conditions: a) Yb(OTf)3 or Y(OTf)3...
Figure 2: Antibacterial activity of GBB adducts 152 against MRSA and VRE; NA = not available.
Figure 3: Antibacterial activity of GBB adduct 153 against Leishmania amazonensis promastigotes and amastigot...
Figure 4: Antiviral and anticancer evaluation of the GBB adducts 154a and 154b. In vitro antiproliferative ac...
Figure 5: Anticancer activity of the GBB-furoxan hybrids 145b, 145c and 145d determined through antiprolifera...
Scheme 45: Synthesis and anticancer activity of the GBB-gossypol conjugates. Conditions: a) Sc(OTf)3 (10 mol %...
Figure 6: Anticancer activity of polyheterocycles 133a and 136a against human neuroblastoma. Clonogenic assay...
Figure 7: Development of GBB-adducts 158a and 158b as PD-L1 antagonists. HTRF assays were carried out against...
Figure 8: Development of imidazo[1,2-a]pyridines and imidazo[1,2-a]pyrazines as TDP1 inhibitors. The SMM meth...
Figure 9: GBB adducts 164a–c as anticancer through in vitro HDACs inhibition assays. Additional cytotoxic ass...
Figure 10: GBB adducts 165, 166a and 166b as anti-inflammatory agents through HDAC6 inhibition; NA = not avail...
Scheme 46: GBB reaction of triphenylamine 167. Conditions: a) NH4Cl (10 mol %), MeOH, 80 °C (MW), 1 h.
Scheme 47: 1) Modified GBB-3CR. Conditions: a) TMSCN (1.0 equiv), Sc(OTf)3 (0.2 equiv), MeOH, 140 °C (MW), 20 ...
Scheme 48: GBB reaction to assemble imidazo-fused heterocycle dimers 172. Conditions: a) Sc(OTf)3 (20 mol %), ...
Figure 11: Model compounds 173 and 174, used to study the acid/base-triggered reversible fluorescence response...
Beilstein J. Org. Chem. 2024, 20, 1817–1830, doi:10.3762/bjoc.20.160
Graphical Abstract
Figure 1: A) The building blocks used in the COMPAS-2 datasets. B) Possible annulation types formed when comb...
Figure 2: Roadmap of the work described in this article. Three main criteria are defined in increasing struct...
Figure 3: Comparison between COMPAS-1 (blue) and COMPAS-2 (purple). A) Principal Moments of Inertia shape dis...
Figure 4: Distributions of electronic properties of the dataset. KDE plots of HOMO, LUMO, Gap, AIP, and AEA c...
Figure 5: KDE distributions of the HOMO, LUMO, and Gap separated and colored by the longest L for: A) all 9-r...
Figure 6: Distributions of molecular properties for 4n and (4n + 2) π-electron count systems, divided by the ...
Figure 7: Stacked histograms showing the prevalence of the different heteroatoms across different areas of th...
Figure 8: Distributions of electronic properties of the dataset. KDE plots of A) HOMO, B) LUMO, C) Gap, D) AI...
Figure 9: A) Scatter plot of the HOMO (x-axis) and LUMO (y-axis) values of the molecules in COMPAS-2. In each...
Figure 10: The effect of multiple heterocycles of a certain type on the A) HOMO, B) LUMO, and C) Gap. For all ...
Beilstein J. Org. Chem. 2024, 20, 1713–1745, doi:10.3762/bjoc.20.152
Graphical Abstract
Figure 1: Steroidal spiro heterocycles with remarkable pharmacological activity.
Scheme 1: Synthesis of the spirooxetanone 2. a) t-BuOK, THF, rt, 16%.
Scheme 2: Synthesis of the 17-spirooxetane derivative 7. a) HC≡C(CH2)2CH2OTBDPS, n-BuLi, THF, BF3·Et2O, −78 °...
Scheme 3: Pd-catalyzed carbonylation of steroidal alkynols to produce α-methylene-β-lactones at C-3 and C-17 ...
Scheme 4: Catalyst-free protocol to obtain functionalized spiro-lactones by an intramolecular C–H insertion. ...
Scheme 5: One-pot procedure from dienamides to spiro-β-lactams. a) 1. Ac2O, DMAP, Et3N, CH2Cl2, 2. malononitr...
Scheme 6: Spiro-γ-lactone 20 afforded from 7α-alkanamidoestrone derivative 17. a) HC≡CCH2OTHP, n-BuLi, THF, –...
Scheme 7: Synthesis of the 17-spiro-γ-lactone 23, a key intermediate to obtain spironolactone. a) Ethyl propi...
Scheme 8: Synthetic pathway to obtain 17-spirodihydrofuran-3(2H)-ones from 17-oxosteroids. a) 1-Methoxypropa-...
Scheme 9: One-pot procedure to obtain 17-spiro-2H-furan-3-one compounds. a) NaH, diethyl oxalate, benzene, rt...
Scheme 10: Synthesis of 17-spiro-2H-furan-3-one derivatives. a) RCH=NOH, N-chlorosuccinimide/CHCl3, 99%; b) H2...
Scheme 11: Intramolecular condensation of a γ-acetoxy-β-ketoester to synthesize spirofuranone 37. a) (CH3CN)2P...
Scheme 12: Synthesis of spiro 2,5-dihydrofuran derivatives. a) Allyl bromide, DMF, NaH, 0 °C to rt, 93%; b) G-...
Scheme 13: First reported synthesis of C-16 dispiropyrrolidine derivatives. a) Sarcosine, isatin, MeOH, reflux...
Scheme 14: Cycloadducts 47 with antiproliferative activity against human cancer cell lines. a) 1,4-Dioxane–MeO...
Scheme 15: Spiropyrrolidine compounds generated from (E)-16-arylidene steroids and different ylides. a) Acenap...
Scheme 16: 3-Spiropyrrolidines 52a–c obtained from ketones 50a–c. a) p-Toluenesulfonyl hydrazide, MeOH, rt; b)...
Scheme 17: 16-Spiropyrazolines from 16-methylene-13α-estrone derivatives. a) AgOAc, toluene, rt, 78–81%.
Scheme 18: 6-Spiroimidazolines 57 synthesized by a one-pot multicomponent reaction. a) R3-NC, T3P®, DMSO, 70 °...
Scheme 19: Synthesis of spiro-1,3-oxazolines 60, tested as progesterone receptor antagonist agents. a) CF3COCF3...
Scheme 20: Synthesis of spiro-1,3-oxazolidin-2-ones 63 and 66a,b. a) RNH2, EtOH, 70 °C, 70–90%; b) (CCl3O)2CO,...
Scheme 21: Formation of spiro 1,3-oxazolidin-2-one and spiro 2-substituted amino-4,5-dihydro-1,3-oxazoles from ...
Scheme 22: Synthesis of diastereomeric spiroisoxazolines 74 and 75. a) Ar-C(Cl)=N-OH, DIPEA, toluene, rt, 74 (...
Scheme 23: Spiro 1,3-thiazolidine derivatives 77–79 obtained from 2α-bromo-5α-cholestan-3-one 76. a) 2-aminoet...
Scheme 24: Method for the preparation of derivative 83. a) Benzaldehyde, MeOH, reflux, 77%; b) thioglycolic ac...
Scheme 25: Synthesis of spiro 1,3-thiazolidin-4-one derivatives from steroidal ketones. a) Aniline, EtOH, refl...
Scheme 26: Synthesis of spiro N-aryl-1,3-thiazolidin-4-one derivatives 91 and 92. a) Sulfanilamide, DMF, reflu...
Scheme 27: 1,2,4-Trithiolane dimers 94a–e selectively obtained from carbonyl derivatives. a) LR, CH2Cl2, reflu...
Scheme 28: Spiro 1,2,4-triazolidin-3-ones synthesized from semicarbazones. a) H2O2, CHCl3, 0 °C, 82–85%.
Scheme 29: Steroidal spiro-1,3,4-oxadiazoline 99 obtained in two steps from cholest-5-en-3-one (97). a) NH2NHC...
Scheme 30: Synthesis of spiro-1,3,4-thiadiazoline 101 by cyclization and diacetylation of thiosemicarbazone 100...
Scheme 31: Mono- and bis(1,3,4-thiadiazolines) obtained from estrane and androstane derivatives. a) H2NCSNHNH2...
Scheme 32: Different reaction conditions to synthesize spiro-1,3,2-oxathiaphospholanes 108 and 109.
Scheme 33: Spiro-δ-lactones derived from ADT and epi-ADT as inhibitors of 17β-HSDs. a) CH≡C(CH2)2OTHP, n-BuLi,...
Scheme 34: Spiro-δ-lactams 123a,b obtained in a five-step reaction sequence. a) (R)-(+)-tert-butylsulfinamide,...
Scheme 35: Steroid-coumarin conjugates as fluorescent DHT analogues to study 17-oxidoreductases for androgen m...
Scheme 36: 17-Spiro estradiolmorpholinones 130 bearing two types of molecular diversity. a) ʟ- or ᴅ-amino acid...
Scheme 37: Steroidal spiromorpholinones as inhibitors of enzyme 17β-HSD3. a) Methyl ester of ʟ- or ᴅ-leucine, ...
Scheme 38: Steroidal spiro-morpholin-3-ones achieved by N-alkylation or N-acylation of amino diols 141, follow...
Scheme 39: Straightforward method to synthesize a spiromorpholinone derivative from estrone. a) BnBr, K2CO3, CH...
Scheme 40: Pyrazolo[4,3-e][1,2,4]-triazine derivatives 152–154. a) 4-Aminoantipyrine, EtOH/DMF, reflux, 82%; b...
Scheme 41: One-pot procedure to synthesize spiro-1,3,4-thiadiazine derivatives. a) NH2NHCSCONHR, H2SO4, dioxan...
Scheme 42: 1,2,4-Trioxanes with antimalarial activity. a) 1. O2, methylene blue, CH3CN, 500 W tungsten halogen...
Scheme 43: Tetraoxanes 167 and 168 synthesized from ketones 163, 165 and 166. a) NaOH, iPrOH/H2O, 80 °C, 93%; ...
Scheme 44: 1,2,4,5-Tetraoxanes bearing a steroidal moiety and a cycloalkane. a) 30% H2O2/CH2Cl2/CH3CN, HCl, rt...
Scheme 45: Spiro-1,3,2-dioxaphosphorinanes obtained from estrone derivatives. a) KBH4, MeOH, THF or CH2Cl2; b)...
Scheme 46: Synthesis of steroidal spiro-ε-lactone 183. a) 1. Jones reagent, acetone, 0 °C to rt, 2. ClCOCOCl, ...
Scheme 47: Synthesis of spiro-2,3,4,7-tetrahydrooxepines 185 and 187 derived from mestranol and lynestrenol (38...
Beilstein J. Org. Chem. 2024, 20, 1510–1517, doi:10.3762/bjoc.20.135
Graphical Abstract
Scheme 1: General illustration of the oxidative α-azidation of carbonyl derivatives using quaternary ammonium...
Scheme 2: Proposed mechanistic scenario.
Scheme 3: Application scope.
Scheme 4: Proof-of-concept for the analogous oxidative α-nitration.
Beilstein J. Org. Chem. 2024, 20, 1376–1395, doi:10.3762/bjoc.20.120
Graphical Abstract
Figure 1: Types and mechanism of the Cannizzaro reaction.
Figure 2: Various approaches of the Cannizzaro reaction.
Figure 3: Representative molecules synthesized via the Cannizzaro reaction.
Scheme 1: Intramolecular Cannizzaro reaction of aryl glyoxal hydrates using TOX catalysts.
Scheme 2: Intramolecular Cannizzaro reaction of aryl methyl ketones using ytterbium triflate/selenium dioxide....
Scheme 3: Intramolecular Cannizzaro reaction of aryl glyoxals using Cr(ClO4)3 as catalyst.
Scheme 4: Cu(II)-PhBox-catalyzed asymmetric Cannizzaro reaction.
Scheme 5: FeCl3-based chiral catalyst applied for the enantioselective intramolecular Cannizzaro reaction rep...
Scheme 6: Copper bis-oxazoline-catalysed intramolecular Cannizzaro reaction and proposed mechanism.
Scheme 7: Chiral Fe catalysts-mediated enantioselective Cannizzaro reaction.
Scheme 8: Ruthenium-catalyzed Cannizzaro reaction of aromatic aldehydes.
Scheme 9: MgBr2·Et2O-assisted Cannizzaro reaction of aldehydes.
Scheme 10: LiBr-catalyzed intermolecular Cannizzaro reaction of aldehydes.
Scheme 11: γ-Alumina as a catalyst in the Cannizzaro reaction.
Scheme 12: AlCl3-mediated Cannizzaro disproportionation of aldehydes.
Scheme 13: Ru–N-heterocyclic carbene catalyzed dehydrogenative synthesis of carboxylic acids.
Figure 4: Proposed catalytic cycle for the dehydrogenation of alcohols.
Scheme 14: Intramolecular desymmetrization of tetraethylene glycol.
Scheme 15: Desymmetrization of oligoethylene glycol dialdehydes.
Scheme 16: Intramolecular Cannizzaro reaction of calix[4]arene dialdehydes.
Scheme 17: Desymmetrization of dialdehydes of symmetrical crown ethers using Ba(OH)2.
Scheme 18: Synthesis of ottelione A (proposed) via intramolecular Cannizzaro reaction.
Scheme 19: Intramolecular Cannizzaro reaction for the synthesis of pestalalactone.
Scheme 20: Synthetic strategy towards nigricanin involving an intramolecular Cannizzaro reaction.
Scheme 21: Spiro-β-lactone-γ-lactam part of oxazolomycins via aldol crossed-Cannizzaro reaction.
Scheme 22: Synthesis of indole alkaloids via aldol crossed-Cannizzaro reaction.
Scheme 23: Aldol and crossed-Cannizzaro reaction towards the synthesis of ertuliflozin.
Scheme 24: Synthesis of cyclooctadieneones using a Cannizzaro reaction.
Scheme 25: Microwave-assisted crossed-Cannizzaro reaction for the synthesis of 3,3-disubstituted oxindoles.
Scheme 26: Synthesis of porphyrin-based rings using the Cannizzaro reaction.
Scheme 27: Synthesis of phthalides and pestalalactone via Cannizarro–Tishchenko-type reaction.
Scheme 28: Synthesis of dibenzoheptalene bislactones via a double intramolecular Cannizzaro reaction.
Beilstein J. Org. Chem. 2024, 20, 1308–1319, doi:10.3762/bjoc.20.114
Graphical Abstract
Figure 1: Reaction yields after seven uses of SSO and average recovery of the oil.
Scheme 1: Synthesis of epoxyisoindole-7-carboxylic acids 2a–m and 2n–p.
Scheme 2: Possible side reactions of unsaturated fatty acids with maleic anhydride.
Figure 2: Coupling constants of selected protons in compound 2a and its optimized geometric structure.
Scheme 3: Equilibrium of 2n–p with maleamic acid precursors.
Figure 3: Possible mechanism for the IMDAF reaction.
Figure 4: IRC calculations of a) endo-, b) exo-transition structures and products for compound 2a (semi-empir...
Beilstein J. Org. Chem. 2024, 20, 1189–1197, doi:10.3762/bjoc.20.101
Graphical Abstract
Scheme 1: Biosynthesis of (A) germacrene A and (B) hedycaryol from FPP. Here the abbreviations represent, FPP...
Figure 1: 6-6 and 5-7 bicyclic carbocations formed by protonation and cyclization of germacrene A and hedycar...
Figure 2: Bar plot for the relative free energies of germacrene A and hedycaryol carbocations relative to car...
Figure 3: NCI plot for A (left) and B (right). Blue corresponds to repulsive and yellow represents slightly a...
Figure 4: NCI plots for F and H hedycaryol cations. The C+···OH distances (Å) are shown in black.
Figure 5: Correlation plot relating between the stability of hedycaryols (ΔΔEe) and C+···OH bond distances.
Beilstein J. Org. Chem. 2024, 20, 1111–1166, doi:10.3762/bjoc.20.98
Graphical Abstract
Scheme 1: General scheme of the borrowing hydrogen (BH) or hydrogen auto-transfer (HA) methodology.
Scheme 2: General scheme for C–N bond formation. A) Traditional cross-couplings with alkyl or aryl halides. B...
Figure 1: Manganese pre-catalysts used for the N-alkylation of amines with alcohols.
Scheme 3: Manganese(I)-pincer complex Mn1 used for the N-alkylation of amines with alcohols and methanol.
Scheme 4: N-Methylation of amines with methanol using Mn2.
Scheme 5: C–N-Bond formation with amines and methanol using PN3P-Mn complex Mn3 reported by Sortais et al. [36]. a...
Scheme 6: Base-assisted synthesis of amines and imines with Mn4. Reaction assisted by A) t-BuOK and B) t-BuON...
Scheme 7: Coupling of alcohols and hydrazine via the HB approach reported by Milstein et al. [38]. aReaction time...
Scheme 8: Proposed mechanism for the coupling of alcohols and hydrazine catalyzed by Mn5.
Scheme 9: Phosphine-free manganese catalyst for N-alkylation of amines with alcohols reported by Balaraman an...
Scheme 10: N-Alkylation of sulfonamides with alcohols.
Scheme 11: Mn–NHC catalyst Mn6 applied for the N-alkylation of amines with alcohols. a3 mol % of Mn6 were used....
Scheme 12: N-Alkylation of amines with primary and secondary alcohols. a80 °C, b100 °C.
Scheme 13: Manganese(III)-porphyrin catalyst for synthesis of tertiary amines.
Scheme 14: Proposed mechanism for the alcohol dehydrogenation with Mn(III)-porphyrin complex Mn7.
Scheme 15: N-Methylation of nitroarenes with methanol using catalyst Mn3.
Scheme 16: Mechanism of manganese-catalyzed methylation of nitroarenes using Mn3 as the catalyst.
Scheme 17: Bidentate manganese complex Mn8 applied for the N-alkylation of primary anilines with alcohols. aOn...
Scheme 18: N-Alkylation of amines with alcohols in the presence of manganese salts and triphenylphosphine as t...
Scheme 19: N-Alkylation of diazo compounds with alcohols using catalyst Mn9.
Scheme 20: Proposed mechanism for the amination of alcohols with diazo compounds catalyzed by catalyst Mn9.
Scheme 21: Mn1 complex-catalyzed synthesis of polyethyleneimine from ethylene glycol and ethylenediamine.
Scheme 22: Bis-triazolylidene-manganese complex Mn10 for the N-alkylation of amines with alcohols.
Figure 2: Manganese complexes applied for C-alkylation reactions of ketones with alcohols.
Scheme 23: General scheme for the C–C bond formation with alcohols and ketones.
Scheme 24: Mn1 complex-catalyzed α-alkylation of ketones with primary alcohols.
Scheme 25: Mechanism for the Mn1-catalyzed alkylation of ketones with alcohols.
Scheme 26: Phosphine-free in situ-generated manganese catalyst for the α-alkylation of ketones with primary al...
Scheme 27: Plausible mechanism for the Mn-catalyzed α-alkylation of ketones with alcohols.
Scheme 28: α-Alkylation of esters, ketones, and amides using alcohols catalyzed by Mn11.
Scheme 29: Mono- and dialkylation of methylene ketones with primary alcohols using the Mn(acac)2/1,10-phenanth...
Scheme 30: Methylation of ketones with methanol and deuterated methanol.
Scheme 31: Methylation of ketones and esters with methanol. a50 mol % of t-BuOK were used, bCD3OD was used ins...
Scheme 32: Alkylation of ketones and secondary alcohols with primary alcohols using Mn4.
Scheme 33: Bidentate manganese-NHC complex Mn6 applied for the synthesis of alkylated ketones using alcohols.
Scheme 34: Mn1-catalyzed synthesis of substituted cycloalkanes by coupling diols and secondary alcohols or ket...
Scheme 35: Proposed mechanism for the synthesis of cycloalkanes via BH method.
Scheme 36: Synthesis of various cycloalkanes from methyl ketones and diols catalyze by Mn13. aReaction time wa...
Scheme 37: N,N-Amine–manganese complex (Mn13)-catalyzed alkylation of ketones with alcohols.
Scheme 38: Naphthyridine‑N‑oxide manganese complex Mn14 applied for the alkylation of ketones with alcohols. a...
Scheme 39: Proposed mechanism of the naphthyridine‑N‑oxide manganese complex (Mn14)-catalyzed alkylation of ke...
Scheme 40: α-Methylation of ketones and indoles with methanol using Mn15.
Scheme 41: α-Alkylation of ketones with primary alcohols using Mn16. aNMR yield.
Figure 3: Manganese complexes used for coupling of secondary and primary alcohols.
Scheme 42: Alkylation of secondary alcohols with primary alcohols catalyzed by phosphine-free catalyst Mn17. a...
Scheme 43: PNN-Manganese complex Mn18 for the alkylation of secondary alcohols with primary alcohols.
Scheme 44: Mechanism for the Mn-pincer catalyzed C-alkylation of secondary alcohols with primary alcohols.
Scheme 45: Upgrading of ethanol with methanol for isobutanol production.
Scheme 46: Mn-Pincer catalyst Mn19 applied for the β-methylation of alcohols with methanol. a2.0 mol % of Mn19...
Scheme 47: Functionalized ketones from primary and secondary alcohols catalyzed by Mn20. aMn20 (5 mol %), NaOH...
Scheme 48: Synthesis of γ-disubstituted alcohols and β-disubstituted ketones through Mn9-catalyzed coupling of...
Scheme 49: Proposed mechanism for the Mn9-catalyzed synthesis of γ-disubstituted alcohols and β-disubstituted ...
Scheme 50: Dehydrogenative coupling of ethylene glycol and primary alcohols catalyzed by Mn4.
Scheme 51: Mn18-cataylzed C-alkylation of unactivated esters and amides with alcohols.
Scheme 52: Alkylation of amides and esters using Mn21.
Scheme 53: α-Alkylation of nitriles with primary alcohols using in situ-generated manganese catalyst.
Scheme 54: Proposed mechanism for the α-alkylation of nitriles with primary alcohols.
Scheme 55: Mn9-catalyzed α-alkylation of nitriles with primary alcohols. a1,4-Dioxane was used as solvent, 24 ...
Figure 4: Manganese complexes used for alkylation of heterocyclic compounds.
Scheme 56: Aminomethylation of aromatic compounds with secondary amines and methanol catalyzed by Mn22.
Scheme 57: Regioselective alkylation of indolines with alcohols catalyzed by Mn9. aMn9 (4 mol %), 48 h.
Scheme 58: Proposed mechanism for the C- and N-alkylation of indolines with alcohols.
Scheme 59: C-Alkylation of methyl N-heteroarenes with primary alcohols catalyzed by Mn1. aTime was 60 h.
Scheme 60: C-Alkylation of oxindoles with secondary alcohols.
Scheme 61: Plausible mechanism for the Mn23-catalyzed C-alkylation of oxindoles with secondary alcohols.
Scheme 62: Synthesis of C-3-alkylated products by coupling alcohols with indoles and aminoalcohols.
Scheme 63: C3-Alkylation of indoles using Mn1.
Scheme 64: C-Methylation of indoles with Mn15 and methanol.
Scheme 65: α-Alkylation of 2-oxindoles with primary and secondary alcohols catalyzed by Mn25. aReaction carrie...
Scheme 66: Dehydrogenative alkylation of indolines with Mn1. aMn1 (5.0 mol %) was used.
Scheme 67: Synthesis of bis(indolyl)methane derivatives from indoles and alcohols catalyzed by Mn26. aMn26 (5....
Scheme 68: One-pot synthesis of pyrimidines via BH.
Scheme 69: Synthesis of pyrroles from alcohols and aminoalcohols using Mn4.
Scheme 70: Synthesis of pyrroles via multicomponent reaction catalyzed by Mn12.
Scheme 71: Friedländer quinoline synthesis using an in situ-generated phosphine-free manganese catalyst.
Scheme 72: Quinoline synthesis using bis-N-heterocyclic carbene-manganese catalyst Mn6.
Scheme 73: Quinoline synthesis using manganese(III)-porphyrin catalyst Mn7.
Scheme 74: Manganese-catalyzed tetrahydroquinoline synthesis via borrowing BH.
Scheme 75: Proposed mechanism for the manganese-catalyzed tetrahydroquinoline synthesis.
Scheme 76: Synthesis of C3-alkylated indoles using Mn24.
Scheme 77: Synthesis of C-3-alkylated indoles using Mn1.
Scheme 78: C–C Bond formation by coupling of alcohols and ylides.
Scheme 79: C-Alkylation of fluorene with alcohols catalyzed by Mn24.
Scheme 80: Proposed mechanism for the C-alkylation of fluorene with alcohols catalyzed by Mn24.
Scheme 81: α-Alkylation of sulfones using Mn-PNN catalyst Mn28.
Beilstein J. Org. Chem. 2024, 20, 1088–1098, doi:10.3762/bjoc.20.96
Graphical Abstract
Figure 1: A) Deamination of cytosine, dC and C as individual nucleosides or as part of a polynucleotide chain...
Scheme 1: i) Boc2O, DMAP, THF, rt, overnight; ii) aq 5 M NaOH, rt, 3 h, 89% yield over two steps; iii) 3, azo...
Scheme 2: i) NaN3, n-Bu4NHSO4, NaHCO3/CHCl3 (1:1), rt, 20 min, 88% yield; ii) a) H2, Pd/C, CH2Cl2, rt, 3 h; b...
Scheme 3: i) H2, 5% Pd/CaCO3/3% Pb, Et3N, CH2Cl2, rt, 1.5 h, 34% and 21% yield for α- and β-anomer of 18, res...
Figure 2: V0 of A3A mimic-catalysed deamination of 5'-dTTTTCAT in the absence (no inhibitor) and presence of ...
Beilstein J. Org. Chem. 2024, 20, 1076–1087, doi:10.3762/bjoc.20.95
Graphical Abstract
Figure 1: Comparison between the light-initiated radical halogenation of toluene (right), and the Ar-SE bromi...
Figure 2: Toluene halogenation mediated by NBS in absence (left) or exposed to light (right).
Figure 3: Scifinder® reaction hits for the structure “as drawn” (January 2024).
Figure 4: Yields obtained in the preparation of aryl-cored halides.
Beilstein J. Org. Chem. 2024, 20, 1069–1075, doi:10.3762/bjoc.20.94
Graphical Abstract
Figure 1: Some examples of biologically active isoxazolo[4,5-b]pyridines with antibacterial [8], anticancer [12] and...
Scheme 1: Methods for the synthesis of isoxazolo[4,5-b]pyridines: (A) annulation of an isoxazole fragment to ...
Scheme 2: Synthesis of ethyl 6-R-isoxazolo[4,5-b]pyridine-3-carboxylates 4a–c.
Scheme 3: Synthesis of isonitroso compounds 7.
Scheme 4: Base-promoted cyclization of compounds 7a–c.
Scheme 5: Synthesis and rearrangement of arylhydrazones 12.
Figure 2: Biologically active analogs of compounds 13.
Figure 3: X-ray crystal structures of compounds 12c (top left; the second crystallographically unique molecul...
Beilstein J. Org. Chem. 2024, 20, 1037–1052, doi:10.3762/bjoc.20.92
Graphical Abstract
Figure 1: Chemical structures of H-bonding N-heteroacenes synthesized by Miao et al. and Bunz et al. (a) [22,23]. Pr...
Scheme 1: Synthesis of dicyanopyrazinoquinoxaline derivatives 1a–7a.
Scheme 2: Synthesis of bis-alkoxy-substituted π-conjugated phenanthrolines 16a, 16b, 16c, and 16d.
Scheme 3: An alternative synthetic route to access 7a.
Scheme 4: Synthesis of DPQDs 1b–7b from their corresponding DCPQs 1a–7a. *THF/H2O/1,4-dioxane (4:5:1). **in s...
Figure 2: TGA of 1a–6a (a) and 1b–7b (b) obtained at 10 °C/min under nitrogen.
Figure 3: Absorption spectra (20 μM) for a) DCPQs 1a–6a and b) DPQDs 1b–7b in dimethyl sulfoxide.
Figure 4: Calculated HOMO (below) and LUMO (above) energies by DFT analysis (B3LYP/6-31+G* level of theory), ...
Figure 5: Calculated HOMO (below) and LUMO (above) energies by DFT analysis (B3LYP/6-31+G* level of theory), ...
Figure 6: Asymmetric unit of DPQD 2b with important bond lengths highlighted (a). Torsion angles of 4.33° and...
Beilstein J. Org. Chem. 2024, 20, 950–958, doi:10.3762/bjoc.20.85
Graphical Abstract
Figure 1: Tetrazole drugs, current assembly strategies, and novel building block strategy.
Scheme 1: Synthesis of tetrazole building blocks. Isolated yields.
Scheme 2: Substrate scope of Passerini products 3. Isolated yields.
Scheme 3: Substrate scope of Ugi products 4 and 5. Isolated yields.
Scheme 4: Synthesis of tetrazole building block 6. Isolated yield.
Beilstein J. Org. Chem. 2024, 20, 931–939, doi:10.3762/bjoc.20.83
Graphical Abstract
Figure 1: Format of a validation report in JSON format. At the top level of the tree, the report contains met...
Figure 2: Left: Graphical representation of the conformational landscape of pyranose sugars. A well-modelled ...
Figure 3: Table of two-dimensional Symbol Nomenclature for Glycan (SNFG) visualisations, which can allow for ...
Figure 4: Table of validation data for each sugar residue within PDB code 3QVP available in the visual valida...
Figure 5: Table of available Privateer reports for the BMA-1,1-TRP linkage in C-glycans (C-mannosylation) sor...
Figure 6: Plot showing trends in deposition in the PDB over time from 1975 to the present. Grey bars show the...