Highly stereoselective preparation of nitro olefins and nitro dienes by the addition-elimination of copper-zinc organometallics to β-alkylthio and β-phenylsulfonyl nitro olefins
作者:Carole Retherford、Paul Knochel
DOI:10.1016/s0040-4039(00)79462-7
日期:1991.1
onyl ethylene 2a gave highly functionalized pure (E) nitro olefins and stereoselectively (1E, 3E) and (1E, 3Z)-1-nitrodienes in excellent yields. β-Alkylthio nitro olefins such as 2-ethylthio-1-nitro-1-cyclohexene 2b and 2,2-dimethylthio-1-nitroethylene 12 were found to have a similar behavior. This methodology allowed an expeditive preparation of the triene 5 which underwent an extremely mild silica
将铜锌有机金属RCu(CN)ZnX加成消除至(E)-1-硝基-2-苯基磺酰基乙烯2a,得到高度官能化的纯(E)硝基烯烃,并立体选择性地(1E,3E)和(1E,3Z) -1-硝基二烯的收率极高。发现β-烷硫基硝基烯烃如2-乙基硫基-1-硝基-1-环己烯2b和2,2-二甲基硫基-1-硝基乙烯12具有相似的行为。该方法学允许快速地制备三烯5,该三烯5经历了极其温和的硅胶催化的立体定向Diels-Alder环化。