Chalcogen electrophile induced rearrangement of 1-alkynyltrialkyl borates: controlled syntheses of trisubstituted olefins from 1-alkynes
作者:Julien Gerard、László Hevesi
DOI:10.1016/s0040-4020(01)00904-8
日期:2001.10
The reaction of 1-alkynyltrialkyl borates with sulfenyl, selenenyl and tellurenyl halides produces β-chalcogeno alkenylboranes in good yields, with a cis relationship between the boron and the chalcogen moities. Protodeborylation of these compounds by acetic acid, or by a transmetalation–protonolysis sequence, leads to vinyl chalcogenides, which can be converted to alkenes by means of a nickel catalyzed
1-炔基三烷基硼酸酯与亚硫基,亚硒基和碲基卤化物的反应以良好的产率产生β-硫属元素烯基硼烷,其中硼与硫属元素之间具有顺式关系。这些化合物通过乙酸或通过金属转移-质子分解序列进行原脱硼化反应,生成乙烯基硫属元素化物,可以通过镍与格利雅试剂的偶联将其转化为烯烃。由于最后两个步骤是在保留立体化学的情况下发生的,因此整个序列代表了高度区域和立体选择性的烯烃合成。