Photoredox-Catalyzed Tandem Insertion/Cyclization Reactions of Difluoromethyl and 1,1-Difluoroalkyl Radicals with Biphenyl Isocyanides
作者:Zuxiao Zhang、Xiaojun Tang、William R. Dolbier
DOI:10.1021/acs.orglett.5b02061
日期:2015.9.18
Usingvisible-lightphotoredox conditions, difluoromethylation and 1,1-difluoroalkylation of biphenyl isocyanides have allowed the synthesis of a series of 6-(difluoromethyl)- and 6-(1,1-difluoroalkyl)phenanthridines via tandem addition/cyclization/oxidation processes. The reactions are carried out in wet dioxane at room temperature using fac-Ir(ppy)3 as catalyst to form a large variety of substituted
Visible-Light-Mediated Fluoroalkylation of Isocyanides with Ethyl Bromofluoroacetates: Unified Synthesis of Mono- and Difluoromethylated Phenanthridine Derivatives
作者:Xiaoyang Sun、Shouyun Yu
DOI:10.1021/ol501081h
日期:2014.6.6
A practical and unified strategy has been described for the preparation of mono- and difluoromethylated phenanthridine derivatives using a visible-light-promoted alkylation and decarboxylation sequence from biphenyl isocyanides with ethyl bromofluoroacetate (EBFA) or ethyl bromodifluoroacetate (EBDFA). These reactions could be carried out at room temperature in good to excellent chemical yields. Both stepwise and one-pot procedures have been developed, which makes this strategy more attractive.