Access to 3-Amino-carbazoles from CF3-3-Indolylmethanols via Sc(OTf)3-Catalyzed C2-Defluorinative Allylation and DBN-Promoted Dedluorinative Annulation

Abstract

A novel method for constructing 3-(2-allyl)-indolyl substituted gem-difluoroalkenes that relies on Sc(OTf)3-catalyzed C2selective allylation/defluorination cascade of trifluoromethylated 3-indolylmethanols has been realized. This diazo-free protocol features exclusive regioselectivity and broad substrate scope. In addition, the application of this protocol has been demonstrated by the one-step transformation of the obtained gem-difluoroalkenes into valuable and functionalized 3amino-carbazole skeletons through DBN-promoted defluorinative annulation under catalyst-free conditions.