Palladium- and Nickel-Catalyzed Kumada Cross-Coupling Reactions of <i>gem</i>-Difluoroalkenes and Monofluoroalkenes with Grignard Reagents
作者:Wenpeng Dai、Juan Xiao、Guanyi Jin、Jingjing Wu、Song Cao
DOI:10.1021/jo5022234
日期:2014.11.7
A novel Kumada–Tamao–Corriu cross-couplingreaction of gem-di- or monofluoroalkenes with Grignard reagents, with or without β-hydrogen atoms, in the presence of a catalytic amount of palladium- or nickel-based catalysts has been developed. The reaction is performed under mild conditions (room temperature or reflux in diethyl ether for 1–2 h) and leads to di-cross- or mono-cross-coupled products in
Sterically Controlled Cu-Catalyzed or Transition-Metal-Free Cross-Coupling of <i>gem</i>-Difluoroalkenes with Tertiary, Secondary, and Primary Alkyl Grignard Reagents
作者:Wenpeng Dai、Hongyan Shi、Xianghu Zhao、Song Cao
DOI:10.1021/acs.orglett.6b02026
日期:2016.9.2
transition-metal-free cross-coupling of gem-difluoroalkenes with tertiary, secondary, and primary alkylGrignardreagents has been developed. Remarkably, the tertiary and secondary alkylation of gem-difluoroalkenes proceeded very smoothly in the presence of 25 mol % of CuCN or under transition-metal-free conditions, affording the tertiary and secondary alkyl-substituted fluoroalkenes in good to excellent yields with
Cooperative NHC/Photoredox Catalyzed Ring‐Opening of Aryl Cyclopropanes to 1‐Aroyloxylated‐3‐Acylated Alkanes
作者:Zhijun Zuo、Constantin G. Daniliuc、Armido Studer
DOI:10.1002/anie.202110304
日期:2021.11.22
Ring-opening/arylcarboxylation/acylation of mono, di and trisubstituted cyclopropanes enabled by cooperative NHC and organophotoredox catalysis for the preparation of γ-aroyloxy ketones is reported. Key step is the radical/radical cross- coupling of a benzylic radical generated in the photoredox catalysis cycle and a ketyl radical formed in the NHC catalysis cycle.
Synthesis of β,β-Disubstituted Styrenes via Trimethylsilyl Trifluoromethanesulfonate-Promoted Aldehyde-Aldehyde Aldol Coupling-Elimination
作者:Grant J. Dixon、Michael R. Rodriguez、Tyler G. Chong、Kevin Y. Kim、C. Wade Downey
DOI:10.1021/acs.joc.2c01458
日期:2022.11.4
α-disubstituted aldehydes condense with electron-rich aromatic aldehydes to yield β,β-disubstituted styrenes. More electron-rich aromatic aldehydes react more rapidly and in higher yield. Preliminary results suggest that the reaction may proceed via the ionization and formal deformylation of an aldol intermediate.