Michael additions of dihydropyrimidines and 2-amino-1,3,4-thiadiazoles to α,β-ethylenic compounds: using polyethylene glycols as a green reaction media
作者:Xicun Wang、Zhengjun Quan、Zhang Zhang
DOI:10.1016/j.tet.2007.05.108
日期:2007.8
Polyethylene glycol (PEG) was found to be an inexpensive, non-toxic, and effective medium for the Michael additions of 3,4-dihydropyrimidines to α,β-ethylenic compounds to provide N3-functionalized dihydropyrimidines in the presence of K2CO3 as the catalyst. Under similar reaction conditions, 2-amino-5-aryloxymethyl-1,3,4-thiadiazoles reacted with methyl acrylate to give unexpected products 5H,6H-[1
发现聚乙二醇(PEG)是廉价的,无毒且有效的介质,用于在K 2 CO存在下将3,4-二氢嘧啶迈克尔加成至α,β-烯键化合物以提供N 3-官能化的二氢嘧啶3作为催化剂。在相似的反应条件下,2-氨基-5-芳氧基甲基-1,3,4-噻二唑与丙烯酸甲酯反应生成意外的产物5 H,6 H- [1,3,4]噻二唑并[1,2- a ]嘧啶通过串联迈克尔加成反应和分子内环化反应得到-7-ones。