Convenient Synthesis of 5-Trifluoroacetylated Imidazoles by Ring Transformation of Mesoionic 1,3-Oxazolium-5-olates.
نویسندگان
چکیده
منابع مشابه
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.
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ژورنال
عنوان ژورنال: Chemical and Pharmaceutical Bulletin
سال: 2000
ISSN: 0009-2363,1347-5223
DOI: 10.1248/cpb.48.410