Department of Chemistry, Indian Institute of Science Education and Research Bhopal, ITI (Gas Rahat) Building, Govindpura, India 460 023.
Org Lett. 2012 Sep 7;14(17):4322-5. doi: 10.1021/ol3015607. Epub 2012 Aug 24.
An efficient enantioselective conjugate addition of malononitrile to a range of β-substituted 2-enoylpyridines catalyzed by cinchona alkaloid-based bifunctional urea catalysts has been developed. Both enantiomers of the products could be achieved with the same level of enantioselectivity by using pseudoenantiomeric catalysts in up to 97% ee and in excellent yields. One of the enantioenriched products has been transformed to a highly functionalized piperidone derivative.
手性金鸡纳生物碱衍生的双功能脲催化剂可以高效地催化一系列β-取代的 2-烯酰基吡啶与丙二腈的对映选择性共轭加成反应。通过使用假对映体催化剂,产物的两种对映异构体都可以达到相同的对映选择性,ee 值最高可达 97%,产率也很高。其中一个对映体富集的产物被转化为一种高度官能化的哌啶酮衍生物。