Synthesis of<i>gem</i>-Difluorocyclopropa(e)nes and O<i>-</i>, S<i>-</i>, N<i>-</i>, and P-Difluoromethylated Compounds with TMSCF<sub>2</sub>Br
作者:Lingchun Li、Fei Wang、Chuanfa Ni、Jinbo Hu
DOI:10.1002/anie.201306703
日期:2013.11.18
Two-in-one: Me3 SiCF2 Br is an efficient difluorocarbene source and is compatible with both neutral and aqueous basic conditions. Bromide-ion-initiated [2+1] cycloaddition with alkenes/alkynes and hydroxide ion promoted α-addition with (thio)phenols, (thio)alcohols, sulfinates, heterocyclic amines, and H-phosphine oxides give the corresponding gem-difluorinated compounds with broad functional-group tolerance.
<i>N</i>-Tosyl-<i>S</i>-difluoromethyl-<i>S</i>-phenylsulfoximine: A New Difluoromethylation Reagent for S-, N-, and C-Nucleophiles
作者:Wei Zhang、Fei Wang、Jinbo Hu
DOI:10.1021/ol900567c
日期:2009.5.21
The first alpha-difluoromethyl sulfoximine compound, 2, was successfully prepared by using the copper(II)-catalyzed nitrene transfer reaction. Compound 2 was found to be a novel and efficient difluoromethylation reagent for transferring the CF2H group to S-, N-, and C-nucleophiles. Deuterium-labeling experiments suggest that a difluorocarbene mechanism is involved in the current difluoromethylation reactions.
N-difluoromethylation of phenylazoles
作者:John W Lyga、Russell M Patera
DOI:10.1016/s0022-1139(98)00262-0
日期:1998.11
In the presence of one equivalent of NaH, 2- and 4-phenylimidazole and 3-phenyl-1,2,4-triazole can be N-difluoromethylated with ClCF2H. The difluoromethylation of 5-phenyltetrazole requires two equivalents of NaH. A mechanism is proposed to account for these differences. (C) 1998 Elsevier Science S.A. All rights reserved.