Novel regioselectivity: three-component cascade synthesis of unsymmetrical 1,4- and 1,2-dihydropyridines.
The three-component sequential reaction of alpha,beta-unsaturated aldehydes, amines, and enaminones proceeded smoothly to give 1,3,4-trisubstituted 1,4-dihydropyridines in aqueous DMF. Moreover, the unexpected regioselective formation of 1,2-dihydropyridines has been observed for the first time in such an approach. On the basis of a systematic study, the novel regioselectivity could be assigned both to steric and electronic effects originating from the amine partner.
Wan
Jie-Ping
JP
Department of Chemistry, Zhejiang University, Hangzhou 310027, People's Republic of China.
Gan
Shi-Feng
SF
Sun
Gong-Lei
GL
Pan
Yuan-Jiang
YJ
D004095:Dihydropyridines / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism
D004095:Dihydropyridines