Bifunctional TEMPO-electrocatalysts enabled enantioselective oxidative lactonization of 1,4-diols

Abstract

Asymmetric electrocatalysis is poised to provide a unique avenue for access to enantioenriched molecules that are difficult to obtain through more conventional approaches, but the development of efficient electrocatalysts capable of highly enantioselective transformations remains elusive. Towards this enviable end, bifunctional electrocatalyst capable of both redox mediation and delivery of high stereocontrol is needed. Here we disclose a novel TEMPO-BOX-ligated copper electrocatalyst that enables oxidative kinetic resolution of racemic 1,4-diols, affording diverse chiral 1,4-diols and γ-lactones with good or excellent chemo-, regio, and enantioselectivity. We also show that this cooperative Cu/TEMPO-BOX catalytic strategy is applicable to the electro-oxidative kinetic resolution of 1,2- and 1,3-amino alcohols. This work demonstrates the potential of bifunctional electrocatalysis for asymmetric synthetic methods and we anticipate that it will spur the development of new hybrid electrocatalysts to realize novel asymmetric electrocatalytic methods.