Copper-catalyzed switchable cyclization of alkyne-tethered α-bromocarbonyls: selective access to quinolin-2-ones and quinoline-2,4-diones

Abstract

Copper-catalyzed cyclization of alkynes has played a significant role in modern catalytic chemistry. However, the selective cyclization in this transformation is extremely limited by the uncontrolled reactivity of the vinyl-Cu^II intermediate. Herein, we describe a practical strategy for controlling the cyclization and oxidative cleavage of the vinyl-Cu^II intermediate, which enables the switchable construction of quinolin-2-ones and quinoline-2,4-diones from alkyne-tethered α-bromocarbonyls by the use of a commercially available copper catalyst under mild conditions.