Enantioselective C(sp(3))-C(sp(3)) cross-coupling of non-activated alkyl electrophiles via nickel hydride catalysis

Cross-coupling of two alkyl fragments is an efficient method to produce organic molecules rich in sp(3)-hybridized carbon centres, which are attractive candidate compounds in drug discovery. Enantioselective C(sp(3))-C(sp(3)) coupling is challenging, especially of alkyl electrophiles without an activating group (aryl, vinyl, carbonyl). Here, we report a strategy based on nickel hydride addition to internal olefins followed by nickel-catalysed alkyl-alkyl coupling. This strategy enables the enantioselective cross-coupling of non-activated alkyl halides with alkenyl boronates to produce chiral alkyl boronates. Employing readily available and stable olefins as pro-chiral nucleophiles, the coupling proceeds under mild conditions and exhibits broad scope and high functional-group tolerance. Applications for the functionalization of natural products and drug molecules, as well as the synthesis of chiral building blocks and a key intermediate to (S)-(+)-pregabalin, are demonstrated. Methods for producing organic molecules rich in sp(3)-hybridized carbon centres can be particularly useful for drug development. Now, it has been shown that the enantioselective cross-coupling of non-activated alkyl halides with alkenyl boronates enables the synthesis of chiral alkyl boronates. The reaction proceeds via nickel hydride insertion into an internal alkene followed by nickel-catalysed alkyl-alkyl cross-coupling.