Diversity‐Oriented Synthesis of Spiro‐ and 3‐Methylene‐hydroquinoline‐Indandiones via an Organobase‐Controlled Cascade Strategy

Abstract

AbstractThe catalyst‐controlled diversity‐oriented synthesis of spirohydroquinoline‐indandiones and 3‐methylenehydroquinoline‐indandiones from ortho‐sulfonamidophenyl‐substituted para‐quinone methides and allylidene‐indandiones is reported. The strategies utilized an organobase such as DMAP or TMG to control the reaction pathway chemoselectively, furnishing the corresponding products in 40–99% yields with excellent diastereoselectivities. The mechanistic studies revealed that spirohydroquinoline‐indandione was the kinetic product to afford 3‐methylenehydroquinoline‐indandione in the presence of TMG, which probably involved an unusual base‐initiated 1,3‐nitrogen rearrangement process.magnified image