Metal‐Free Oxidative Annulation/Cyclization of 1,6‐Enynes for the Synthesis of 4‐Carbonylquinolines
作者:Xiao‐Feng Xia、Wei He、Dawei Wang
DOI:10.1002/adsc.201900013
日期:2019.6.18
Herein we report on the development of a metal‐freeoxidativeannulation reaction of 1,6‐enynes, leading to 4‐carbonylquinolines by using dioxygen as a green sustainable oxidant. Key advances include the use of readily available tert‐butyl nitrite (TBN) to promote radical annulation of 1,6‐enynes and easy‐to‐handle reaction conditions. Preliminary mechanistic studies including radical capture reactions
A synthetic method of highly substituted quinolines has been developed from N-(2-alkynylaryl)enamine carboxylates under Cu-catalyzed aerobic conditions via intramolecular carbo-oxygenation of alkynes. This strategy was further applied for N-alkynylamidines for amino-oxygenation of alkynes, leading to imidazole and quinazoline derivatives.