A highly efficient and practical preparation of 2,4-pentadienyltitaniums and their γ-selective addition reaction with aldehydes and ketones

A variety of penta-2,4-dienyltitanium complexes including those having a functional group were readily prepared from a divalent titanium reagent, Ti(O–i-Pr)4/2i-PrMgCl, and penta-1,4-dien-3-ol or penta-2,4-dien-1-ol derivatives, and the organotitaniums thus prepared reacted with aldehydes and ketones smoothly to afford the corresponding penta-1,4-dien-3-yl carbinols highly predominantly in excellent yield.