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Search for "homo-coupling" in Full Text gives 33 result(s) in Beilstein Journal of Organic Chemistry.
Use of mixed Li/K metal TMP amide (LiNK chemistry) for the synthesis of [2.2]metacyclophanes
- Marco Blangetti,
- Patricia Fleming and
- Donal F. O'Shea
Beilstein J. Org. Chem. 2011, 7, 1249–1254, doi:10.3762/bjoc.7.145
- ]. We envisaged that our LiNK metalation conditions with in situ oxidative coupling could offer a facile general approach to [2.2]metacyclophanes, which would be of general synthetic interest (Scheme 2). Oxidative homo-coupling of benzyl anions has previously been noted, but it has remained relatively
Graphical Abstract
Scheme 1: Selective benzylic metalation with LiNK conditions. DG = directing group.
Scheme 2: Iterative LiNK/oxidative coupling synthesis of [2.2]metacyclophanes.
Figure 1: Xylene substrates.
Figure 2: Metalation selectivity for 4e (arrows indicate potential metalation sites). 2H NMR spectrum in CH2Cl...
Figure 3: Di-metalation selectivity for 6f. 2H NMR spectrum in CH2Cl2. *CD2Cl2.
Figure 4: X-Ray structure of 8c with thermal ellipsoids drawn at 50% probability level.
Homocoupling of aryl halides in flow: Space integration of lithiation and FeCl3 promoted homocoupling
- Aiichiro Nagaki,
- Yuki Uesugi,
- Yutaka Tomida and
- Jun-ichi Yoshida
Beilstein J. Org. Chem. 2011, 7, 1064–1069, doi:10.3762/bjoc.7.122
- transmetalation of the aryl group from lithium to iron followed by reductive elimination of the homo-coupling product seems to be plausible, while a similar mechanism is proposed for homo-coupling of organomagnesium compounds with FeCl3 [19][20]. The regiospecificity of the coupling is consistent with this
Graphical Abstract
Scheme 1: Halogen–lithium exchange of p-bromoanisole followed by reaction with methanol.
Figure 1: Flow microreactor system for halogen–lithium exchange of aryl halide followed by reaction with meth...
Figure 2: Effects of the temperature (T) and the residence time in R1 (tR1) on the yield of anisole in the Br...
Scheme 2: Halogen-lithium exchange of p-bromoanisole followed by oxidative homocoupling with FeCl3.
Figure 3: Integrated flow microreactor system for oxidative homocoupling reaction of aryllithium with FeCl3. ...
Figure 4: Effects of the temperature (T) and the residence time in R2 (tR2) on the yield of 4,4'-dimethoxybip...
Recent advances in the gold-catalyzed additions to C–C multiple bonds
- He Huang,
- Yu Zhou and
- Hong Liu
Beilstein J. Org. Chem. 2011, 7, 897–936, doi:10.3762/bjoc.7.103
- . reported a general gold-catalyzed direct oxidative homo-coupling of non-activated arenes 207 (Scheme 38). The reaction protocol tolerates a wide range of functional groups [92]. All halogens survive the reaction, which provides the potential for further reactions. 4.2 Rearrangements and ring enlargement A
Graphical Abstract
Scheme 1: Gold-catalyzed addition of alcohols.
Scheme 2: Gold-catalyzed cycloaddition of alcohols.
Scheme 3: Ionic liquids as the solvent in gold-catalyzed cycloaddition.
Scheme 4: Gold-catalyzed cycloaddition of diynes.
Scheme 5: Gold(I) chloride catalyzed cycloisomerization of 2-alkynyl-1,5-diols.
Scheme 6: Gold-catalyzed cycloaddition of glycols and dihydroxy compounds.
Scheme 7: Gold-catalyzed ring-opening of cyclopropenes.
Scheme 8: Gold-catalyzed intermolecular hydroalkoxylation of alkynes. PR3 = 41–45.
Scheme 9: Gold-catalyzed intramolecular 6-endo-dig cyclization of β-hydroxy-α,α-difluoroynones.
Scheme 10: Gold-catalyzed intermolecular hydroalkoxylation of non-activated olefins.
Scheme 11: Preparation of unsymmetrical ethers from alcohols.
Scheme 12: Expedient synthesis of dihydrofuran-3-ones.
Scheme 13: Catalytic approach to functionalized divinyl ketones.
Scheme 14: Gold-catalyzed glycosylation.
Scheme 15: Gold-catalyzed cycloaddition of aldehydes and ketones.
Scheme 16: Gold-catalyzed annulations of 2-(ynol)aryl aldehydes and o-alkynyl benzaldehydes.
Scheme 17: Gold-catalyzed addition of carboxylates.
Scheme 18: Dual-catalyzed rearrangement reaction of allenoates.
Scheme 19: Meyer–Schuster rearrangement of propargylic alcohols.
Scheme 20: Propargylic alcohol rearrangements.
Scheme 21: Gold-catalyzed synthesis of imines and amine alkylation.
Scheme 22: Hydroamination of allenes and allenamides.
Scheme 23: Gold-catalyzed inter- and intramolecular amination of alkynes and alkenes.
Scheme 24: Gold-catalyzed cycloisomerization of O-propioloyl oximes and β-allenylhydrazones.
Scheme 25: Intra- and intermolecular amination with ureas.
Scheme 26: Gold-catalyzed cyclization of ortho-alkynyl-N-sulfonylanilines and but-3-yn-1-amines.
Scheme 27: Gold-catalyzed piperidine ring synthesis.
Scheme 28: Ring expansion of alkylnyl cyclopropanes.
Scheme 29: Gold-catalyzed annulations of N-propargyl-β-enaminones and azomethine imines.
Scheme 30: Gold(I)-catalyzed cycloisomerization of aziridines.
Scheme 31: AuCl3/AgSbF6-catalyzed intramolecular amination of 2-(tosylamino)phenylprop-1-en-3-ols.
Scheme 32: Gold-catalyzed cyclization via a 7-endo-dig pathway.
Scheme 33: Gold-catalyzed synthesis of fused xanthines.
Scheme 34: Gold-catalyzed synthesis of amides and isoquinolines.
Scheme 35: Gold-catalyzed oxidative cross-coupling reactions of propargylic acetates.
Scheme 36: Gold-catalyzed nucleophilic addition to allenamides.
Scheme 37: Gold-catalyzed direct carbon–carbon bond coupling reactions.
Scheme 38: Gold-catalyzed C−H functionalization of indole/pyrrole heterocycles and non-activated arenes.
Scheme 39: Gold-catalyzed cycloisomerization of cyclic compounds.
Scheme 40: Gold-catalyzed cycloaddition of 1-aryl-1-allen-6-enes and propargyl acetates.
Scheme 41: Gold(I)-catalyzed cycloaddition with ligand-controlled regiochemistry.
Scheme 42: Gold(I)-catalyzed cycloaddition of dienes and enynes.
Scheme 43: Gold-catalyzed intramolecular cycloaddition of 3-alkoxy-1,5-enynes and 2,2-dipropargylmalonates.
Scheme 44: Gold-catalyzed intramolecular cycloaddition of 1,5-allenynes.
Scheme 45: Gold(I)-catalyzed cycloaddition of indoles.
Scheme 46: Gold-catalyzed annulation reactions.
Scheme 47: Gold–carbenoid induced cleavage of a sp3-hybridized C−H bond.
Scheme 48: Furan- and indole-based cascade reactions.
Scheme 49: Tandem process using aromatic alkynes.
Scheme 50: Gold-catalyzed cycloaddition of 1,3-dien-5-ynes.
Scheme 51: Gold-catalyzed cascade cyclization of diynes, propargylic esters, and 1,3-enynyl ketones.
Scheme 52: Tandem reaction of β-phenoxyimino ketones and alkynyl oxime ethers.
Scheme 53: Gold-catalyzed tandem cyclization of enynes, 2-(tosylamino)phenylprop-1-yn-3-ols, and allenoates.
Scheme 54: Cyclization of 2,4-dien-6-yne carboxylic acids.
Scheme 55: Gold(I)-catalyzed tandem cyclization approach to tetracyclic indolines.
Scheme 56: Gold-catalyzed tandem reactions of alkynes.
Scheme 57: Aminoarylation and oxyarylation of alkenes.
Scheme 58: Cycloaddition of 2-ethynylnitrobenzene with various alkenes.
Scheme 59: Gold-catalyzed tandem reactions of allenoates and alkynes.
Scheme 60: Gold-catalyzed asymmetric synthesis of 2,3-dihydropyrroles.
Scheme 61: Chiral [NHC–Au(I)]-catalyzed cyclization of enyne.
Scheme 62: Gold-catalyzed hydroaminations and hydroalkoxylations.
Scheme 63: Gold(I)-catalyzed asymmetric hydroalkoxylation of 1,3-dihydroxymethyl-2-alkynylbenzene chromium com...
Scheme 64: Gold-catalyzed synthesis of julolidine derivatives.
Scheme 65: Gold-catalyzed the synthesis of chiral fused heterocycles.
Scheme 66: Gold-catalyzed asymmetric reactions with 3,5-(t-Bu)2-4-MeO-MeOBIPHEP.
Scheme 67: Gold-catalyzed cyclization of o-(alkynyl) styrenes.
Scheme 68: Asymmetric gold(I)-catalyzed redox-neutral domino reactions of enynes.
Scheme 69: Gold(I)-catalyzed enantioselective polyene cyclization reaction.
Scheme 70: Gold(I)-catalyzed enantioselective synthesis of benzopyrans.
Scheme 71: Gold(I)-catalyzed enantioselective ring expansion of allenylcyclopropanols.
Ring strain and total syntheses of modified macrocycles of the isoplagiochin type
- Andreas Speicher,
- Timo Backes,
- Kerstin Hesidens and
- Jürgen Kolz
Beilstein J. Org. Chem. 2009, 5, No. 71, doi:10.3762/bjoc.5.71
- [25] – only 30% yield beside the undesired homo-coupling product 17. A modified and palladium free procedure, however [26], resulted – after acidic workup liberating the aldehyde group – in a satisfactory yield of the mixed tolane 16 as the a-b-c precursor (Scheme 4). Two different building blocks 22
Graphical Abstract
Figure 1: Structures of isoplagiochins C (1) and D (2) (with aryl fragments a–d and possible conformational b...
Figure 2: Possible stereoisomers of 1 as conformers C1–C4 relative to the configurationally stable biaryl axi...
Scheme 1: Stereochemical correlation for 1 and 2. (*: configurationally stable, (*): configurationally semi-s...
Figure 3: Temperature dependent 1H NMR and assignment of methoxy signals in the tetramethyl ether 3.
Scheme 2: Strategy of synthesis for the macrocycles 5–7.
Scheme 3: Preparation of the terminal alkyne 13 as a–b part (TBATB = tetrabutylammonium tribromide).
Scheme 4: Sonogashira-type coupling to the tolane 16.
Scheme 5: Synthesis of the d building blocks 21 and 26. aThe original procedure in diluted ammonia [31] was repla...
Scheme 6: Synthesis of the tolane precursors 27 and 28 for cyclization.
Scheme 7: Synthesis of the modified macrocycles 5–7 from the dialdehyde precursors 28–30.
Scheme 8: Synthesis of the known macrocycle 3 via McMurry reaction.
From discovery to production: Scale- out of continuous flow meso reactors
- Peter Styring and
- Ana I. R. Parracho
Beilstein J. Org. Chem. 2009, 5, No. 29, doi:10.3762/bjoc.5.29
- performed using a 1:1 substrate ratio with 67% conversion to the desired 4-methoxybiphenyl. The production of biphenyl as a homo-coupling product was also observed in a significant amount of approximately 20% of the final mixture. Indeed, the problem of homo-coupling was encountered in earlier publications
- -methoxybiphenyl yield. A comparative study of 1:1 and 1:2 of 4-bromoanisole to phenylmagnesium chloride was then undertaken in a batch process and the production of biphenyl as well as 4,4′-dimethoxybiphenyl was monitored. The nickel complex catalyst instigates the homo-coupling of the Grignard reagent, in this
Graphical Abstract
Scheme 1: Synthesis of 4-methoxybiphenyl (4-MeOBP) and by-products in the Kumada reaction.
Figure 1: Stainless steel single column flow reactor for discovery scale synthesis.
Figure 2: (a): Schematic diagram of the parallel reactor housing (dimensions in mm); (b) the stainless steel ...
Figure 3: Schematic diagram of the pneumatic pumping system.
Scheme 2: Proposed catalytic cycles for the transformation of 4-haloanisole (Ar-X) and Grignard reagent (RMgX...
Figure 4: Comparative study of flow rates in a single channel meso flow reactor. The output was sampled hourl...
Figure 5: Kumada reaction carried out in a parallel channel meso reactor at a flow rate of 95 ml h−1.
Figure 6: Kumada reaction carried out in a parallel channel meso reactor over a 31-hour period at a flow rate...
Figure 7: Kumada reaction carried out in a parallel channel meso reactor at a flow rate of 190 ml h−1.
Reduction of arenediazonium salts by tetrakis(dimethylamino)ethylene (TDAE): Efficient formation of products derived from aryl radicals
- Mohan Mahesh,
- John A. Murphy,
- Franck LeStrat and
- Hans Peter Wessel
Beilstein J. Org. Chem. 2009, 5, No. 1, doi:10.3762/bjoc.5.1
- donor in specific organometallic reactions, such as the chromium-mediated allylation of aldehydes and ketones [54][55] and the palladium-catalyzed reductive homo-coupling of aryl halides to afford the corresponding biaryls [56][57][58][59] illustrate further versatility of the reagent. The fact that
Graphical Abstract
Scheme 1: Aza- and thia-substituted electron donors.
Scheme 2: Radical-polar crossover reaction of arenediazonium salts by TTF.
Scheme 3: Studies on the reductive radical cyclization of arenediazonium salt 16 by TDAE.
Scheme 4: Preparation of the arenediazonium salts 31a–d. Reagents and conditions: (a) 23, NaH, THF, 0 °C, 0.5...
Scheme 5: Cascade radical cyclizations of arenediazonium salts 42 and 44 by TDAE. Reagents and conditions: (a...
Scheme 6: TDAE-mediated radical based addition-elimination route to indoles.
Scheme 7: Cyclization of the arenediazonium salts 49b–d by TDAE. Reagents and conditions: (a) NOBF4, CH2Cl2, ...
Scheme 8: Cyclization of the arenediazonium salt 62 by TDAE. Reagents and conditions: (a) 2-Nitrobenzenesulfo...
Scheme 9: Mechanism for the formation of the tetracyclic sulfonamide 65.
Scheme 10: Possible mechanism for the formation of indole (63) and indole sulfonamide 64.
Recent progress on the total synthesis of acetogenins from Annonaceae
- Nianguang Li,
- Zhihao Shi,
- Yuping Tang,
- Jianwei Chen and
- Xiang Li
Beilstein J. Org. Chem. 2008, 4, No. 48, doi:10.3762/bjoc.4.48
Graphical Abstract
Scheme 1: Total synthesis of longifolicin by Marshall’s group.
Scheme 2: Total synthesis of corossoline by Tanaka’s group.
Scheme 3: Total synthesis of corossoline by Wu’s group.
Scheme 4: Total synthesis of pseudo-annonacin A by Hanessian’s group.
Scheme 5: Total synthesis of tonkinecin by Wu’s group.
Scheme 6: Total synthesis of gigantetrocin A by Shi’s group.
Scheme 7: Total synthesis of annonacin by Wu’s group.
Scheme 8: Total synthesis of solamin by Kitahara’s group.
Scheme 9: Total synthesis of solamin by Mioskowski’s group.
Scheme 10: Total synthesis of cis-solamin by Makabe’s group.
Scheme 11: Total synthesis of cis-solamin by Brown’s group.
Scheme 12: The formal synthesis of (+)-cis-solamin by Donohoe’s group.
Scheme 13: Total synthesis of cis-solamin by Stark’s group.
Scheme 14: Total synthesis of mosin B by Tanaka’s group.
Scheme 15: Total synthesis of longicin by Hanessian’s group.
Scheme 16: Total synthesis of murisolin and 16,19-cis-murisolin by Tanaka’s group.
Scheme 17: Synthesis of a stereoisomer library of (+)-murisolin by Curran’s group.
Scheme 18: Total synthesis of murisolin by Makabe’s group.
Scheme 19: Total synthesis of reticulatain-1 by Makabe’s group.
Scheme 20: Total synthesis of muricatetrocin C by Ley’s group.
Scheme 21: Total synthesis of (4R,12S,15S,16S,19R,20R,34S)-muricatetrocin (146) and (4R,12R,15S,16S,19R,20R,34S...
Scheme 22: Total synthesis of parviflorin by Hoye’s group.
Scheme 23: Total synthesis of parviflorin by Trost’s group.
Scheme 24: Total synthesis of trilobacin by Sinha’s group.
Scheme 25: Total synthesis of 15-epi-annonin I 181b by Scharf’s group.
Scheme 26: Total synthesis of squamocin A and squamocin D by Scharf’s group.
Scheme 27: Total synthesis of asiminocin by Marshall’s group.
Scheme 28: Total synthesis of asiminecin by Marshall’s group.
Scheme 29: Total synthesis of (+)-(30S)-bullanin by Marshall’s group.
Scheme 30: Total synthesis of uvaricin by the group of Sinha and Keinan.
Scheme 31: Formal synthesis of uvaricin by Burke’s group.
Scheme 32: Total synthesis of trilobin by Marshall’s group.
Scheme 33: Total synthesis of trilobin by the group of Sinha and Keinan.
Scheme 34: Total synthesis of asimilobin by the group of Wang and Shi.
Scheme 35: Total synthesis of squamotacin by the group of Sinha and Keinan.
Scheme 36: Total synthesis of asimicin by Marshall’s group.
Scheme 37: Total synthesis of asimicin by the group of Sinha and Keinan.
Scheme 38: Total synthesis of asimicin by Roush’s group.
Scheme 39: Total synthesis of asimicin by Marshall’s group.
Scheme 40: Total synthesis of 10-hydroxyasimicin by Ley’s group.
Scheme 41: Total synthesis of asimin by Marshall’s group.
Scheme 42: Total synthesis of bullatacin by the group of Sinha and Keinan.
Scheme 43: Total synthesis of bullatacin by Roush’s group.
Scheme 44: Total synthesis of bullatacin by Pagenkopf’s group.
Scheme 45: Total synthesis of rollidecins C and D by the group of Sinha and Keinan.
Scheme 46: Total synthesis of 30(S)-hydroxybullatacin by Marshall’s group.
Scheme 47: Total synthesis of uvarigrandin A and 5(R)-uvarigrandin A by Marshall’s group.
Scheme 48: Total synthesis of membranacin by Brown’s group.
Scheme 49: Total synthesis of membranacin by Lee’s group.
Scheme 50: Total synthesis of rolliniastatin 1 and rollimembrin by Lee’s group.
Scheme 51: Total synthesis of longimicin D by the group of Maezaki and Tanaka.
Scheme 52: Total synthesis of the structure proposed for mucoxin by Borhan’s group.
Scheme 53: Modular synthesis of adjacent bis-THF annonaceous acetogenins by Marshall’s group.
Scheme 54: Total synthesis of 4-deoxygigantecin by Tanaka’s group.
Scheme 55: Total synthesis of squamostatins D by Marshall’s group.
Scheme 56: Total synthesis of gigantecin by Crimmins’s group.
Scheme 57: Total synthesis of gigantecin by Hoye’s group.
Scheme 58: Total synthesis of cis-sylvaticin by Donohoe’s group.
Scheme 59: Total synthesis of 17(S),18(S)-goniocin by Sinha’s group.
Scheme 60: Total synthesis of goniocin and cyclogoniodenin T by the group of Sinha and Keinan.
Scheme 61: Total synthesis of jimenezin by Takahashi’s group.
Scheme 62: Total synthesis of jimenezin by Lee’s group.
Scheme 63: Total synthesis of jimenezin by Hoffmann’s group.
Scheme 64: Total synthesis of muconin by Jacobsen’s group.
Scheme 65: Total synthesis of (+)-muconin by Kitahara’s group.
Scheme 66: Total synthesis of muconin by Takahashi’s group.
Scheme 67: Total synthesis of muconin by the group of Yoshimitsu and Nagaoka.
Scheme 68: Total synthesis of mucocin by the group of Sinha and Keinan.
Scheme 69: Total synthesis of mucocin by Takahashi’s group.
Scheme 70: Total synthesis of (−)-mucocin by Koert’s group.
Scheme 71: Total synthesis of mucocin by the group of Takahashi and Nakata.
Scheme 72: Total synthesis of mucocin by Evans’s group.
Scheme 73: Total synthesis of mucocin by Mootoo’s group.
Scheme 74: Total synthesis of (−)-mucocin by Crimmins’s group.
Scheme 75: Total synthesis of pyranicin by the group of Takahashi and Nakata.
Scheme 76: Total synthesis of pyranicin by Rein’s group.
Scheme 77: Total synthesis of proposed pyragonicin by the group of Takahashi and Nakata.
Scheme 78: Total synthesis of pyragonicin by Rein’s group.
Scheme 79: Total synthesis of pyragonicin by Takahashi’s group.
Scheme 80: Total synthesis of squamostanal A by Figadère’s group.
Scheme 81: Total synthesis of diepomuricanin by Tanaka’s group.
Scheme 82: Total synthesis of (−)-muricatacin [(R,R)-373a] and its enantiomer (+)-muricatacin [(S,S)-373b] by ...
Scheme 83: Total synthesis of epi-muricatacin (+)-(S,R)-373c and (−)-(R,S)-373d by Scharf’s group.
Scheme 84: Total synthesis of (−)-muricatacin 373a and 5-epi-(−)-muricatacin 373d by Uang’s group.
Scheme 85: Total synthesis of four stereoisomers of muricatacin by Yoon’s group.
Scheme 86: Total synthesis of (+)-muricatacin by Figadère’s group.
Scheme 87: Total synthesis of (+)-epi-muricatacin and (−)-muricatacin by Couladouros’s group.
Scheme 88: Total synthesis of muricatacin by Trost’s group.
Scheme 89: Total synthesis of (−)-(4R,5R)-muricatacin by Heck and Mioskowski’s group.
Scheme 90: Total synthesis of muricatacin (−)-373a by the group of Carda and Marco.
Scheme 91: Total synthesis of (−)- and (+)-muricatacin by Popsavin’s group.
Scheme 92: Total synthesis of (−)-muricatacin by the group of Bernard and Piras.
Scheme 93: Total synthesis of (−)-muricatacin by the group of Yoshimitsu and Nagaoka.
Scheme 94: Total synthesis of (−)-muricatacin by Quinn’s group.
Scheme 95: Total synthesis of montecristin by Brückner’s group.
Scheme 96: Total synthesis of (−)-acaterin by the group of Franck and Figadère.
Scheme 97: Total synthesis of (−)-acaterin by Singh’s group.
Scheme 98: Total synthesis of (−)-acaterin by Kumar’s group.
Scheme 99: Total synthesis of rollicosin by Quinn’s group.
Scheme 100: Total synthesis of Rollicosin by Makabe’s group.
Scheme 101: Total synthesis of squamostolide by Makabe’s group.
Scheme 102: Total synthesis of tonkinelin by Makabe’s group.
A convenient catalyst system for microwave accelerated cross- coupling of a range of aryl boronic acids with aryl chlorides
- Matthew L. Clarke,
- Marcia B. France,
- Jose A. Fuentes,
- Edward J. Milton and
- Geoffrey J. Roff
Beilstein J. Org. Chem. 2007, 3, No. 18, doi:10.1186/1860-5397-3-18
- ). Buchwald and co-workers have previously noted the failure of 2,4,6-trifluorophenyl boronic acid to react with aryl chlorides, although the origin of this effect was not identified. The origin of this low reactivity could be due to slow transmetalation, [35][36][37][38] homo-coupling problems,[39] or Pd
Graphical Abstract
Scheme 1: Catalysts used in this study and microwave accelerated cross-coupling of functionalised boronic aci...
Scheme 2: Microwave accelerated cross-coupling of a range of boronic acids with 4-chloroacetophenone.
Scheme 3: Competition experiment demonstrating the inhibitory effect of 2,3,6-trifluorophenyl boronic acid on...
Scheme 4: Stoichiometric reactions between fluorinated boronic acids and [Pd(dppf)Cl2].
