Cobalt Carbonyl as a Solid CO(g) Source for the Synthesis of Novel Coumarin Derivatives and Biaryl Ketones by Palladium‐Catalyzed Carbonylative Suzuki–Miyaura Reaction

Abstract

We herein report an atom‐economical, facile, and efficient approach developed for synthesizing a variety of C‐7 carbonylated coumarin derivatives and biaryl ketones in good‐to‐excellent yields. The use of aryl fluorosulfates as an atom‐economical electrophilic coupling partner and the employment of cobalt carbonyl as a solid source of gaseous CO in the palladium‐catalyzed carbonylative Suzuki–Miyaura reaction are the key for success of this developed protocol. The excellent reactivity of coumarin fluorosulfate as a leaving group for the carbonylative Suzuki reaction has been realized by doing a comparative study with other pseudohalide leaving groups in the later stage. The practical utility of the developed methodology has been demonstrated by performing a gram‐scale synthesis of phenstatin derivative of 4‐methyl coumarin.