Abstract : α-Selenoenones could be employed as Z -allyl precursors in the chiral amine-catalyzed asymmetric conjugate addition of aldehydes. Abstract : α-Selenoenones could be employed as Z -allyl precursors in the chiral amine-catalyzed asymmetric conjugate addition of aldehydes. The obtained formal allylation product, a Z -olefin having a sulfonate leaving group, was employed as a synthetically useful chiral alkylating agent.