Cui Sun-Liang, Wang Jun, Lin Xu-Feng, Wang Yan-Guang
Department of Chemistry, Zhejiang University, Hangzhou 310027, China.
J Org Chem. 2007 Sep 28;72(20):7779-82. doi: 10.1021/jo7013593. Epub 2007 Sep 7.
A novel synthesis of Hantzsch-type N-substituted 1,4-dihydropyridines from salicaldehydes, ethyl propiolate, and amines has been developed. Salicaldehydes were treated with ethyl propiolate in the presence of N-methylmorpholine to give ethyl 3-(2-formylphenoxy)propenoates. Three equivalents of ethyl 3-(2-formylphenoxy)propenoates reacted with 1 equiv of amines under trifluoroacetic acid (TFA) catalyst to furnish the corresponding N-substituted 1,4-dihydropyridines in good to excellent yields, recovering the starting material salicaldehydes. A possible mechanism for the domino process was proposed. Furthermore, the products can be easily derived via further transformations and three of them exhibited strong fluorescence (Phif = 0.36-0.63).
已开发出一种从水杨醛、丙炔酸乙酯和胺类化合物新颖合成汉茨施型N-取代1,4-二氢吡啶的方法。水杨醛在N-甲基吗啉存在下与丙炔酸乙酯反应，得到3-(2-甲酰基苯氧基)丙烯酸乙酯。三当量的3-(2-甲酰基苯氧基)丙烯酸乙酯在三氟乙酸（TFA）催化剂作用下与1当量的胺类化合物反应，以良好至优异的产率提供相应的N-取代1,4-二氢吡啶，同时回收起始原料水杨醛。提出了多米诺过程的可能机理。此外，产物可通过进一步转化轻松衍生，其中三种表现出强荧光（荧光量子产率Phif = 0.36 - 0.63）。
