Studies on chemoselective synthesis of 1,4- and 1,2-dihydropyridine derivatives by a Hantzsch-like reaction: a combined experimental and DFT study
作者:Peng Li、Shijie Wang、Nana Tian、Hong Yan、Juan Wang、Xiuqing Song
DOI:10.1039/d0ob02289f
日期:——
propiolate as raw materials. The mechanisms for the formation of 1,4-DHP and 1,2-DHP were proposed based on the isolated intermediate named diethyl 4-((phenylamino)methylene)pent-2-enedioate generated by the Michael addition of aniline and ethyl propiolate. The transition state structures were optimized and the reaction energy barriers of intermediates in the speculated mechanisms were calculated by DFT
The multicomponentreactions of aldehydes, electron deficient alkynes and amines have been successfully performed to yield a number of symmetrical 2,6‐unsubstituted 1,4‐dihydropyridines (1,4‐DHPs). This method has been found generally applicable for the synthesis of both N‐substituted and N‐unsubstituted 1,4‐DHPs by employing secondary amine to activate the alkyne component via enaminoester intermediates