An aqua mediated facile synthesis of conformationally restricted polycyclic dihydropyridines

作者：Kidwai Mazaahir^*; Kukreja Shuchi; Rastogi Shweta; Singhal Kavita; Mishra Neeraj Kumar

来源：Indian Journal of Chemistry - Section B: Organic and Medicinal Chemistry , 2014, 53(5): 605-609.

• Conformationally restricted dihydropyridines
• 4-hydroxycoumarin
• aqueous medium
• microwaves

An economically and environmentally benign synthesis of 4-substituted-dihydropyridines (DHPs) is described from readily accessible 4-hydroxy coumarin with aldehydes and ammonium nitrate that are accelerated by exposure to microwaves. The reaction completes within a few minutes with good yields. The mechanistic detail of methodology includes Michael type addition of beta-aminobenzopyran-2-one across the double bond of arylidine formed by the condensation of 4-hydroxycoumarin with aldehyde in aq. medium. The main advantages of the protocol reported here is absence of use of strong acid or expensive catalyst, good yields, easy work-up and almost no effluent generation.

• 出版日期2014-5