Tandem reductive lithiations ? Carbanionic cyclizations yielding sulfur stabilized cyclopropyl- and cyclobutylcarbinyllithiums
作者:Fangping Chen、Boguslaw Mudryk、Theodore Cohen
DOI:10.1016/s0040-4020(98)01141-7
日期:1999.3
nucleophilic addition to the vinyl sulfide group, usually at −78 °C, leading to a phenylthio-stabilized cyclopropyl- or cyclobutylcarbinyllithium. The substrates were prepared by Wittig or Peterson olefination of carbonyl compounds which were in turn generated by conjugate addition of thiophenol or of the cuprate of a phenylthio-stabilized carbanion to an α,β-unsaturated carbonyl compound.
1,4-或1,5-双(苯硫基)-1-烯烃与芳族自由基阴离子的还原锂化导致仅被连接至sp 3碳原子的苯硫基的锂原子取代。所得的碳负离子通常在-78°C下对乙烯基硫醚基团进行分子内亲核加成,从而生成苯硫基稳定的环丙基或环丁基羰基锂。底物是通过对化合物进行Wittig或Peterson烯化来制备的,该羰基化合物是通过将硫酚或苯硫基稳定化的碳负离子的铜酸盐与α,β-不饱和羰基化合物共轭加成而生成的。