Synthesis of <i>gem</i>‐Difluorocyclopropa(e)nes and O<i>‐</i>, S<i>‐</i>, N<i>‐</i>, and P‐Difluoromethylated Compounds with TMSCF₂Br

Abstract

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.