Deciphering the Keys for High Enantioselectivity in Hypervalent Iodine-Catalyzed 1,2-Difunctionalization: Improved Synthesis of Ishihara-Muñiz Precatalysts

Org Lett. 2021 Aug 20;23(16):6429-6434. doi: 10.1021/acs.orglett.1c02252. Epub 2021 Aug 4.

Abstract

In the course of upscaling the synthesis of enantiopure aryliodine precatalysts, we detected an unreported meso form of the catalysts for the first time. A new scalable route was developed to avoid epimerization of the lactamide arms, providing syntheses of the precatalysts that are both more effective and much less time-consuming. The catalysts obtained with these synthetic procedures have been employed in some published reactions, reaching the maximum ee ever reported.