The asymmetric conjugate addition of diethyl zinc to cyclohexen-2-one occurs with 0.5% copper (II) triflate and 1 % chiral phosphite. Cyclic phosphites derived from various tartrates gave a moderate enantiomeric excess. The nature of the exocyclic substituent of the dioxaphospholane ring is important, but the chiral induction is imposed by the tartrate framework.