Enantioselective alkyl-alkyl coupling by Ni-catalysed asymmetric cross-hydrodimerization of alkenes

Saturated tertiary stereogenic carbon centres are common in small molecules and organic materials. Transition-metal-catalysed asymmetric alkyl-alkyl bond formation processes represent contemporary techniques for the straightforward and efficient construction of saturated tertiary stereogenic carbon centres. However, reaction modes for asymmetric alkyl-alkyl bond formation between sp3-hybridized carbon atoms, C(sp3)-C(sp3), are limited yet highly desirable. Here a mode for asymmetric alkyl-alkyl bond formation enabled by Ni-catalysed asymmetric alkyl-alkyl cross-coupling between alkenes has been developed to construct tertiary stereogenic carbon centres. Ni-catalysed asymmetric cross-hydrodimerization of N-acyl enamines and unactivated alkenes enables head-to-tail regioselectivity and excellent levels of chemo- and enantioselectivity. Notably, the reaction proceeds in the presence of both reducing and oxidizing reagents, rendering alkenes as the sole precursors to forge enantioselective alkyl-alkyl bonds. The exclusive head-to-tail cross-hydrodimerization of distinct alkenes opens the way to access saturated tertiary stereogenic carbon centres from alkenes. Methods for asymmetric alkyl-alkyl bond formation between sp3-hybridized carbon atoms, C(sp3)-C(sp3), are limited yet highly desirable. Now an approach for asymmetric alkyl-alkyl bond formation by Ni-catalysed cross-coupling between alkenes has been developed to construct tertiary stereogenic carbon centres with head-to-tail regioselectivity and excellent chemo- and enantioselectivity.