作者:J.J. Burger、T.B.R.A. Chen、E.R. De Waard、H.O. Huisman
DOI:10.1016/0040-4020(80)80086-x
日期:1980.1
4-addition of the lithiated sulfones 5 and 6. The cyclisation of Z-sulfone 1 has been used for the isolation of the isomeric E-sulfone 2 from mixtures of 1 and 2. The lithiated sulfones 4–6 are chlorinated with hexachloroethane (HCE). Due to acid/base reactions the α,α-dichlorinated cyclic sulfone 23 and α,α'-dichlorinated butadienyl sulfones 13–15 are formed in small amounts.
在-78°下用二异丙基氨基锂(LDA)锂化1-3中的砜1–3具有区域选择性,因为α-锂砜4的氘化会导致α-单十二烷基砜7的形成。较高的温度会导致分子内1,4-锂化砜-addition 4到锂化环状砜19和分子间1,4-加成锂化砜的5和6。Z-砜1的环化已用于从1和1的混合物中分离异构体E-砜22。锂化的砜4-6用六氯乙烷(HCE)进行了氯化。由于酸/碱反应,少量形成了α,α-二氯环砜23和α,α'-二氯丁二烯砜13-15。