Organocatalytic direct difluoromethylation of aldehydes and ketones with TMSCF<sub>2</sub>H
作者:Guang-Fen Du、Ying Wang、Cheng-Zhi Gu、Bin Dai、Lin He
DOI:10.1039/c5ra04472c
日期:——
Organocatalytic direct difluoromethylation of aldehydes and ketones with TMSCF2H.
有机催化剂直接用TMSCF2H对醛和酮进行二氟甲基化。
Direct Nucleophilic Difluoromethylation of Carbonyl Compounds
作者:Zuyong Deng、Jin-Hong Lin、Ji Cai、Ji-Chang Xiao
DOI:10.1021/acs.orglett.6b01425
日期:2016.7.1
Phosphonium salt ([Ph3P+CF2H] Br–, DFPB) was found to be an efficient nucleophilic difluoromethylation reagent. Although DFPB is known as a phosphonium ylide precursor, its reaction with carbonylcompounds under traditional “Wittig reaction conditions” did not give the expected Wittig difluoroolefinated products, but afforded the nucleophilic difluoromethylation products, α-CF2H alcohols. Mechanistic
Toward a Unified Mechanism for Oxoammonium Salt-Mediated Oxidation Reactions: A Theoretical and Experimental Study Using a Hydride Transfer Model
作者:Trevor A. Hamlin、Christopher B. Kelly、John M. Ovian、Rebecca J. Wiles、Leon J. Tilley、Nicholas E. Leadbeater
DOI:10.1021/acs.joc.5b01240
日期:2015.8.21
A range of oxoammonium salt-based oxidation reactions have been explored computationally using density functional theory (DFT), and the results have been correlated with experimentally derived trends in reactivity. Mechanistically, most reactions involve a formal hydride transfer from an activated C–H bond to the oxygen atom of the oxoammonium cation. Several new potential modes of reactivity have
Visible light-promoted umpolung coupling of aryl tri-/difluoroethanones with 2-alkenylpyridines
作者:Xiao Xu、Qing-Qiang Min、Na Li、Feng Liu
DOI:10.1039/c8cc06748a
日期:——
Tertiaryalcohols bearing a trifluoromethyl group are of considerable medicinal interest. Using an umpolung strategy, we herein report the first intermolecular reductive cross-coupling of aryl tri-/difluoroethanones with 2-alkenylpyridines with the aid of a Brønsted acid catalyst upon visible-light irradiation. This metal-free reaction is operationally simple and performed at ambient temperature, allowing