Reactions of lithiated (E)-3-halo-1-phenylsulfonylprop-1-enes and (Z)-1-halo-3-phenylsulfonylprop-1-enes with aldehydes
作者:Eva T. Gallagher、David H. Grayson
DOI:10.1039/b300925b
日期:2003.4.14
(E)-3-Chloro-1-phenylsulfonylprop-1-ene and its iodo- and bromo- analogues, (Z)-1-iodo-3-phenylsulfonylprop-1-ene and (Z)-1-bromo-3-phenylsulfonylprop-1-ene, have each been successfully converted into lithiated carbanions which react regioselectively with aromatic aldehydes to give γ-alkylated products whose nature depends upon the halogen substituent: the chloro-sulfones yield (2Z)-1-aryl-2-chloro-4-phenylsulfonylbut-2-en-1-ols but the bromo- and iodo-derivatives behave differently, yielding (1E)-trans-4-aryl-3,4-epoxy-1-phenylsulfonylbut-1-enes. In sharp contrast, the same lithiated sulfones react with aliphatic aldehydes to give anti-configured β-hydroxysulfones which are formed via diastereoselective α-alkylation reactions.
(E)-3-氯-1-苯磺酰基丙-1-烯及其碘和溴类似物,(Z)-1-碘-3-苯磺酰基丙-1-烯和(Z)-1-溴-3-苯磺酰基丙-1-烯,均已成功转化为石碳酸化物,这些石碳酸化物可与芳香醛发生区域选择性反应,生成γ-烷基化产物,其性质取决于卤素取代基:氯砜会生成 (2Z)-1- 芳基-2-氯-4-苯磺酰基丁-2-烯-1-醇,但溴和碘衍生物的表现不同,会生成 (1E)-trans-4- 芳基-3,4-环氧-1-苯磺酰基丁-1-烯。与此形成鲜明对比的是,同样的石化砜与脂肪族醛发生反应,生成反构型的 β-羟基砜,这种砜是通过非对映选择性的 α-烷基化反应生成的。