A simple approach to pyrrolylimidazole derivatives by azirine ring expansion with imidazolium ylides
作者:Alexander F. Khlebnikov、Olesya A. Tomashenko、Liya D. Funt、Mikhail S. Novikov
DOI:10.1039/c4ob00865k
日期:——
A domino reaction of 2H-azirines with 1-alkyl-3-phenacyl-1H-imidazolium bromides in the presence of Et3N provides a facile route to 1-alkyl-3-(1H-pyrrol-3-yl)-1H-imidazol-3-ium bromides. 1-Benzyl derivatives can be reduced to 1-(1H-pyrrol-3-yl)-1H-imidazoles with HCO2NH4 on Pd/C. The action of KOH on pyrrolylimidazolium salts leads to a new type of stable ylide, 3-(1H-imidazol-3-ium-3-yl)-pyrrol-1-ides