Lewis acid-catalyzed asymmetric radical additions of trialkylboranes to (1R,2S,5R)-2-(1-methyl-1-phenylethyl)-5-methylcyclohexyl-2H-azirine-3-carboxylate
作者:Erik Risberg、Andreas Fischer、Peter Somfai
DOI:10.1016/j.tet.2005.06.076
日期:2005.8
The asymmetric addition of alkyl radicals to (1R,2S,5R)-2-(1-methyl-1-phenylethyl)-5-methylcyclohexyl-2H-azirine-3-carboxylate (1) yielding the corresponding 2-alkylaziridine-2-carboxylates has been investigated. High diastereoselectivities and good yields were obtained in the addition of primary alkyl radicals to azirine 1, while secondary radicals gave a lower dr. The influence of Lewis acids was
烷基不对称加成到(1 R,2 S,5 R)-2-(1-甲基-1-苯乙基)-5-甲基环己基-2 H-叠氮基-3-羧酸酯(1)中,得到相应的2-已经研究了烷基氮丙啶-2-羧酸盐。向azirine 1添加伯烷基可获得高非对映选择性和良好的收率,而仲自由基给出了较低的dr。还研究了路易斯酸的影响。发现10mol%的CuCl增加了dr。