Regio-Reversed Alkenyl-Arylation of Ynamides via 1,3-Olefin Shift

Abstract

A cationic Pd-catalysed multicomponent reaction enables the regio-reversed alkenyl–arylation of ynamides through a migratory difunctionalization strategy. A stereoselective 1,3-olefin shift of a keteniminium–alkenyl–Pd intermediate governs the carbopalladation pathway, generating a vinylic Pd species that subsequently couples with aryl boronates. This protocol offers streamlined access to highly substituted branched dienes, trienes, and divinyl ethylene (DVE) derivatives with excellent regio- and stereocontrol. The broad substrate scope, scalability, and mechanistic insights highlight the synthetic potential of this transformation. Additionally, the photophysical properties of these conjugated systems were examined, underscoring their potential as functional materials for optoelectronic applications.