Novel and Efficient Synthesis of 2-Aminooxazoles from Pyrimidin-2(1<i>H</i>)-one
作者:Eugene Babaev、Vadim Alifanov
DOI:10.1055/s-2006-958941
日期:2007.1
Stepwise conversion of pyrimidin-2(1H)-one to 2-amino-5-aryloxazoles via oxazolo[3,2-a]pyrimidinium salts is reported. The sequence involves, (i) regioselective N-alkylation of pyrimidone by phenacyl bromides, (ii) cyclization of obtained 1-(2-aryl-2-oxoethyl)pyrimidin-2(1H)-ones into oxazolo[3,2-a]pyrimidinium salts under the action of fuming sulfuric (or triflic) acid, and (iii) reaction of the obtained