Reyes Efraim, Vicario Jose L, Carrillo Luisa, Badía Dolores, Uria Uxue, Iza Ainara
Departamento de Química Organica II, Facultad de Ciencia y Tecnología, Universidad del País Vasco/Euskal Herriko Unibertsitatea, P.O. Box 644, E-48080 Bilbao, Spain.
J Org Chem. 2006 Sep 29;71(20):7763-72. doi: 10.1021/jo061205e.
Organolithium reagents undergo highly regio- and diastereoselective 1,4-addition to (S,S)-(+)-pseudoephedrine enamides furnishing the corresponding beta-alkyl-substituted adducts in excellent yields and diastereoselectivities. In addition, the intermediate lithium enolates generated after the conjugate addition step undergo a highly diastereoselective alkylation reaction, furnishing alpha,beta-dialkyl-substituted amides in high yields. The obtained adducts have been converted into chiral nonracemic beta-alkyl- and alpha,beta-dialkyl-substituted carboxylic acids and gamma-alkyl- and beta,gamma-dialkyl-substituted alcohols using very simple and high-yielding procedures.
有机锂试剂对（S，S）-（+）-伪麻黄碱烯酰胺进行高度区域和非对映选择性的1,4-加成反应，以优异的产率和非对映选择性得到相应的β-烷基取代加合物。此外，共轭加成步骤后生成的中间体烯醇锂盐进行高度非对映选择性的烷基化反应，以高收率得到α，β-二烷基取代的酰胺。使用非常简单且高产率的方法，已将所得加合物转化为手性非外消旋的β-烷基-和α，β-二烷基取代的羧酸以及γ-烷基-和β，γ-二烷基取代的醇。
