Regioselective alkenylation of masked carboxylic acid derivatives of coumarins with acrylates via oxidative C(sp2)–C(sp2) cross-coupling

Abstract

Here, we demonstrate the regio-selective C–H alkenylation reaction with acrylates by a rhodium-catalyzed reaction of PMS (phenylmethyl sulfoximine) directed 2-oxo-2H-chromene-3-carboxylic acid derivatives. The current C(sp²)–C(sp²) cross-coupling strategy could deliver a variety of C4-alkenylated coumarin carboxylic acid manifolds in an economical fashion. The key aspects of this method encompass its one-pot nature, straightforward workup process, higher yields, broad substrate compatibility, including various functional groups, and suitability for scale-up synthesis. The derivatives of the current protocol are also highly useful in attaining the various alkenylated coumarin-derived acid derivatives, which can also be useful for the synthesis of complex drug molecules.