Catalytic Enantioselective Hydroxylation of Tertiary Propargylic C(sp³)–H Bonds in Acyclic Systems: a Kinetic Resolution Study

Abstract

Direct site-selective and enantioselective oxyfunctionalization of C(sp 3 )−H bonds to form alcohols with a general scope, with predictable selectivities, and in preparatively useful yields represents a paradigm shift in the standard logic of synthetic organic chemistry. However, the knowledge of either enzymatic or nonenzymatic asymmetric hydroxylation of tertiary C−H bonds for enantioenriched tertiary alcohol synthesis is sorely lacking. Here, we report a practical manganese-catalyzed enantio-differentiating hydroxylation of tertiary propargylic C−H bonds in acyclic systems, producing a wide range of structurally diverse enantioenriched tertiary propargyl alcohols in high efficiency with extremely efficient chemo-and enantio-discrimination. Other features include the use of C−H substrates as the limiting reagent, noteworthy functional group compatibility, great synthetic utilities, and scalability. The findings serve as a blueprint for the development of metal-catalyzed asymmetric oxidation of challenging substrates.