Nickel-catalyzed α-allylation of aldehydes and tandem aldol condensation/allylation reaction with allylic alcohols

An additive-free nickel-catalyzed alpha-allylation of aldehydes with allyl alcohol is reported. The reaction is promoted by 1 mol% of in situ formed nickel complex in methanol, and water is the sole by-product of the reaction. The experimental conditions allow the conversion of various alpha-branched aldehydes and alpha, beta-unsaturated aldehydes as nucleophiles. The same catalyst and reaction conditions enabled a tandem aldol condensation of aldehyde/alpha-allylation reaction