Nickel-catalyzed allylation of lithium 1-alkynyl(trialkoxy)borates with 1,3-disubstituted allyl carbonates

The first Suzuki-type cross-coupling of alkynylborates with 1,3-disubstitued allyl carbonates was studies. It was found that nickel complexes readily catalyzed the reaction giving normal coupling products in good to excellent yields. The nickel complexes of dppe or dppen revealed a higher catalytic activity than that of NiCl2(PPh3)2 or NiCl2(dppf). This is a substrate-controlled reaction with high regioselectivity. The asymmetric cross-coupling reaction of alkynylborates with allyl carbonate enantioselectively produced an allyl substituted alkyne with 13%ee.