Enantioselective Cobalt-Catalyzed Intermolecular Hydroacylation of 1,6-Enynes

Abstract

We report a cobalt-catalyzed hydroacylation of 1,6-enynes with exogenous aldehydes in a domino sequence to construct enantioenriched ketones. The products were obtained in good yields with excellent regio-, diastereo-, and enantioselectivity. Furthermore, the chiral products served as valuable precursors to access complex spirocyclic scaffolds with three contiguous stereocenters. The asymmetric hydroacylation process exhibited no C-H crossover and no KIE, thus indicating that the C-H bond cleavage was not involved in the turnover-limiting step.

Keywords: C−H functionalization; cobalt; enynes; homogeneous catalysis; hydroacylation.