Stabilization of Transient 3-Chloroindolenines Enables Diverse Functionalization.

Transient intermediates as highly reactive species are difficult to manipulate due to their poor stability. Stabilization of unstable intermediates for functionalization is an attractive approach, but the practical applications are still rare. Herein, we explore a strategy that could effectively stabilize labile 3-chloroindolenines and significantly improve the lifetime from seconds to weeks. This chemistry was utilized to enable the synthesis of 55 diverse compounds which are unable to be achieved by traditional approach.