3,4-Bisthiolated pyrroles constitute key cores in pyrrole-based semiconductors, and their electronic properties could be improved by the bisthio groups via the S-effect. Herein, a convenient method for the synthesis of 3,4-bisthiolated pyrroles has been developed through the AlCl3-catalyzed thiolation/cyclization of homopropargylic azides, and cyclic voltammetry and DFT calculations indicated that
phenylmercuric acetate and trifluoromethanesulfonic acid or silica gel supported phenylmercuric trifluoromethanesulfonate (silaphenyl mercuric triflate) efficiently catalyzed the formation of pyrroles from homopropargyl azide derivatives. The reactions proceed using 20 mol% of the heterogeneous catalyst with yields of isolated pyrroles ranging from 74% to 99%. cyclization - heterocycles - heterogeneous
Copper-Catalyzed Cascade Transformation of Homopropargyl Azides into Trifluoromethylated Nitriles via C–C Cleavage
作者:Shuang Chen、Deng-Yuan Li、Liang-Liang Jiang、Kai Liu、Pei-Nian Liu
DOI:10.1021/acs.orglett.7b00571
日期:2017.4.21
A cascade reaction of homopropargyl azides in the presence of a Cu catalyst was achieved, affording 3-(trifluoromethyl)but-3-enenitriles with good yields and excellent regioselectivity. This reaction appears to be the first direct conversion of homopropargyl azides into trifluoromethylated nitriles. Mechanisticstudies indicate that the transformation proceeds by addition of a CF3 radical to the alkyne