Second-Layer Chiral Environment-Induced Steric Hindrance Enables Catalyst Conformation Lockdown in Enantioselective Hypervalent Iodine Organocatalysis

A classof confined chiral hypervalent iodines have been designedand developed by incorporating two sterically demanding BINOL-derivedunits, which form the second-layer chiral environment, into the iodine-containingmolecules to lock down the conformation of the catalyst and indirectlycreate a compact chiral environment around the active site. Good-to-excellentenantioselectivities have been achieved with these catalysts for the alpha-oxysulfonylation of ketones (up to 97.5:2.5 er) and the oxidativecyclization of 5-oxo-5-arylpentanoic acids to gamma-butyrolactones(up to 98:2 er), thereby demonstrating the utility of this strategyfor catalyst design.

Automated summary

A class of confined chiral hypervalent iodines, designed by incorporating two sterically demanding BINOL-derived units, demonstrated good-to-excellent enantioselectivities in the α-oxysulfonylation of ketones (up to 97.5:2.5 er) and the oxidative cyclization of 5-oxo-5-arylpentanoic acids to γ-butyrolactones (up to 98:2 er), showing the effectiveness of this catalyst design strategy.