Allenic zinc reagents (R1R2C CC (R3) ZnL) are efficiently prepared by the reaction of propargylic substrates (R1R2C (X) C⋮ CH, X= MeSO2O, Cl, R2NCO2) with a variety of triorganozincates ((R3) 3ZnM; R3= alkyl, alkenyl, aryl, M= Li, MgCl). Treatment of the allenic zinc reagents with D2O gives the corresponding deuteroallenes with high deuterium incorporation. The allenic zinc reagents thus prepared undergo a coupling reaction with a ...