Base-Catalyzed Regio-and Stereoselective Addition of Isatins to Trifluoromethylated Alkynes for Preparation of N-Alkenylisatins

Abstract

A direct addition of isatins to trifluoromethylated internal alkynes was developed under simple and mild environmental benign inorganic base catalytic condition. A series of intended N-alkenylisatins were readily assembled with good functional group compatibility and diversity. Meanwhile, exclusive regio- and stereoselectivity were achieved to provide the β- adducts with Z-configuration only. Taking advantage of its intrinsic versatile reactivity, N-alkenylisatin product was transformed into useful 2-phenyl-3-(trifluoromethyl)quinoline-4-carboxylates via one-step late-stage derivatization. In addition, a group of control experiments were designed and implemented to shed light on possible reaction mechanism.