Stereoselective syntheses of 1,2-dialkyl-1-phenyl cyclopentanes involving intramolecular carbolithiation of α-thioalkenes
作者:Alain Krief、Benoît Kenda、Bruno Remacle
DOI:10.1016/0040-4020(96)00261-x
日期:1996.5
2-Ethyl-1-methyl-1-phenyl cyclopentane, unavailable by butyllithium-promoted carbocyclisation of the corresponding alkenyl selenide, has been synthesized from 6-methylseleno-6-phenyl-1-phenylthio-1-heptene and 7-methylseleno-7-phenyl-2-phenylthio-2-octene with high stereocontrol at all the three stereogenic centers. Depending upon the solvent used, the derivative in which the methyl- and the phenylthiomethyl
由6-甲基硒基-6-苯基-1-苯基硫基-1-庚烯和7-甲基硒基-7合成了2-乙基-1-甲基-1-苯基环戊烷,这是丁基锂促进的相应烯基硒化物的碳环化无法得到的。在所有三个立体异构中心均具有高度立体控制的-苯基-2-苯基硫基-2-辛烯。根据所使用的溶剂,选择性地形成其中甲基和苯硫基甲基彼此为顺式(在THF中)或反式(在戊烷中)的衍生物。