Low-temperature n-butyllithium-induced rearrangement of allyl 1,1-dichlorovinyl ethers

reaction: see text]. Upon treatment with n-BuLi at low temperatures, a variety of allyl 1,1-dichlorovinyl ethers 2 undergo rearrangement to furnish gamma,delta-unsaturated esters 3 after alcohol addition. Compounds containing quaternary centers (3e: R1 = H, R2, R3 = -(CH2)5-; 3f: R1 = H, R2 = CH3, R3 = (CH2)2CH(CH3)2) may be formed in high yield and under mild conditions utilizing this protocol. The reaction is stereospecific and may be applied to the preparation of Delta(2,3)-beta-C-glycosides and alpha,beta-disubstituted lactones.