Highly regioselective α-alkylation of α,β,γ,δ-unsaturated aldehydes.

The first α-alkylation of α,β,γ,δ-unsaturated aldehydes is achieved under mild reaction conditions. Several α,β,γ,δ-unsaturated aldehydes and diarylcarbinols are successfully tested for the synthesis of MBH-type α-alkylated products with an excellent regioselectivity. Simple pyrrolidine is efficiently used as a catalyst to achieve a perfect E/Z selectivity of the α-alkylated products.