Dehalogenative Regiospecific Amination of 4-Bromo-1,1,2-trifluoro-1-butene with N -Heterocycles: Synthesis of 1,2-Difluorobuta-1,3-dien-1-yl Azaarenes

We have developed a selective dehalogenative amination of 4-bromo-1,1,2-trifluoro-1-butene with nitrogen-containing heteroarenes, furnishing a series of N-difluorovinyl heteroarenes with excellent regioselectivity and stereoselectivity. This methodology is free of high-pressure acetylene or transition-metal catalysis, and delivers high yields. It displays good substrate compatibility with a variety of nitrogen heterocycles, including indole, benzimidazole, benzotriazole, and carbazole.