GaBr3-catalyzed Coupling between α-Iodo Esters with Alkynylstannanes under UV Irradiation

Abstract

A coupling between various alkynylstannanes with α-iodo esters was catalyzed by GaBr3 under UV irradiation conditions, for which a catalytic amount of GaBr3 was essential, and a radical coupling with the generated alkynylgallium species was involved. The desired α-alkynyl esters were selectively obtained even in the presence of an aryl–I bond, which is a reactive site in a conventional palladium-catalyzed system.

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