Convenient synthesis of 5-trifluoroacetylated imidazoles by ring transformation of mesoionic 1,3-oxazolium-5-olates.
Mesoionic 4-trifluoroacetyl-1,3-oxazolium-5-olates (1), obtained from the reaction of N-acyl-N-alkylglycines (2) with trifluoroacetic anhydride, react with amidines to give 5-trifluoroacetylimidazoles (3) in moderate yield. The novel ring transformations of 1 into 3 occur via an initial attack of amidines on the C-2 position of the ring.
Kawase
M
M
Faculty of Pharmaceutical Sciences, Josai University, Sakado, Saitama, Japan.
Saito
S
S
D004791:Enzyme Inhibitors / Q000138:chemical synthesis* / Q000494:pharmacology; D007093:Imidazoles / Q000138:chemical synthesis* / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D010080:Oxazoles / Q000138:chemical synthesis* / Q000494:pharmacology; D013055:Spectrophotometry, Infrared
D004791:Enzyme Inhibitors; D007093:Imidazoles; D010080:Oxazoles