Copper-catalyzed chemoselective synthesis of 4-trifluoromethyl pyrazoles.

ABSTRACT: A series of 4-trifluoromethyl pyrazoles have been prepared via the copper-catalyzed cycloaddition of 2-bromo-3,3,3-trifluoropropene with a variety of N-arylsydnone derivatives under mild conditions. This new protocol under optimized reaction conditions [Cu(OTf)₂/phen, DBU, CH₃CN, 35 °C] afforded 4-trifluoromethyl pyrazoles in moderate to excellent yields with excellent regioselectivity.

SUBMITTER: Lu J 

PROVIDER: S-EPMC9072218 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature