Benzenesulfonylcarbonitrile oxide. 5. Face selectivity of cycloaddition to chiral terminal alkenes
作者:Peter A. Wade、Shankar M. Singh、M.Krishna Pillay
DOI:10.1016/0040-4020(84)85065-6
日期:1984.1
The diastereomer ratio for cycloaddition of benzenesulfonylcarbonitrile oxide (BSNO) to a series of (S)-vinylglycine-derived alkenes varied from 30:70 to 66:34 depending on the substitutents at the chiral center. Isomer ratios were routinely determined by 1H-NMR; isolation confirmed the results in several cases. Isomer assignment was based on comparison to acivicin where the absolute configuration
取决于手性中心的取代基,苯磺酰基氧化丙烯腈(BSNO)与一系列(S)-乙烯基甘氨酸衍生的烯烃环加成的非对映异构体比率在30:70至66:34之间变化。异构体比例通常通过1 H-NMR确定;隔离证实了几种情况下的结果。异构体分配是基于与阿维西林的比较,后者通过X射线分析确定了绝对构型。结果被解释为与竞争性加成成环烯烃成两种不同构象的烯烃相一致。