Development of methods for the synthesis of chiral, highly functionalized 2-amino-4-aryl-4H-pyrans
作者:José L. Marco、Nazario Martín、Angeles Martínez-Grau、Carlos Seoane、Armando Albert、Félix H. Cano
DOI:10.1016/s0040-4020(01)87029-0
日期:1994.3
The development of new methods for the asymmetric synthesis of highly functionalized 2-amino-4-aryl-4H-pyrans is described. Two alternative synthetic routes: the 1,4-conjugate addition of chiral β-ketoesters 3 or the N-acetoacetyl sultam 11 to arylidenemalononitriles 6, and the Michael addition of malononitrile to enantiomerically pure α-acetylcinnamates 5, have been designed. Depending upon the chiral
描述了不对称合成高度官能化的2-氨基-4-芳基-4 H-吡喃的新方法的开发。两个替代的合成路线:1,4-共轭加成的手性β酮酯的3或Ñ -acetoacetyl磺内酰胺11至arylidenemalononitriles 6,并且迈克尔加成丙二腈对映异构体纯α-acetylcinnamates 5,已经设计。取决于手性助剂,以低[(-)-薄荷醇,(-)-冰片,(-)-乳酸乙酯]至良好(Oppolzer's sultam)非对映异构体过量得到所得的4 H-吡喃。化合物12a的次要异构体中新立体中心的绝对构型通过X射线衍射分析确定为S。用氢化铝锂对4 H-吡喃12进行的还原裂解得到对映体纯的或富集的醇14。