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
Bis(difluoromethyl)trimethylsilicate Anion: A Key Intermediate in Nucleophilic Difluoromethylation of Enolizable Ketones with Me<sub>3</sub>SiCF<sub>2</sub>H
作者:Dingben Chen、Chuanfa Ni、Yanchuan Zhao、Xian Cai、Xinjin Li、Pan Xiao、Jinbo Hu
DOI:10.1002/anie.201605280
日期:2016.10.4
A pentacoordinate bis(difluoromethyl)silicate anion, [Me3Si(CF2H)2]−, is observed for the first time by the activation of Me3SiCF2H with a nucleophilic alkali‐metal salt and 18‐crown‐6. Further study on its reactivity by tuning the countercationeffect led to the discovery and development of an efficient, catalytic nucleophilic difluoromethylation of enolizable ketones with Me3SiCF2H by using a combination