Reductive 1,2-Arylation of Isatins

Org Lett. 2022 Oct 7;24(39):7232-7236. doi: 10.1021/acs.orglett.2c03042. Epub 2022 Sep 28.

Abstract

We report an intermolecular Ni-catalyzed reductive coupling of aryl iodides and isatins to form 3-hydroxyoxindoles. In contrast to common metal-mediated methods, sec-butanol is used as a mild stoichiometric reductant resulting in benign waste products. This formal 1,2-addition reaction is facilitated by a 1,5-diaza-3,7-diphosphacyclooctane (P2N2) ligand. Two Ni(0)-P2N2 species are prepared and found to be catalytically active, supporting a mechanistic hypothesis that this reaction proceeds by a modified carbonyl-Heck-type pathway.