Selective remote esterification of 8-aminoquinoline amides via copper(ii)-catalyzed C(sp2)–O cross-coupling reaction†
Abstract
The remote C–O coupling of quinoline amides at the C5 position has been established using cheap and readily available copper catalyst under mild conditions. The positionally selective esterification protocol afforded C–O coupling products in moderate to excellent yields. Most importantly, this method may provide a potential alternative to the existing ways to build functionalized 5-hydroxyquinoline derivatives, which are utilized as pivotal intermediates in the synthesis of drug candidates.