Convenient synthesis of 5-trifluoroacetylated imidazoles by ring transformation of mesoionic 1,3-oxazolium-5-olates.
نویسندگان
چکیده
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.
منابع مشابه
Convenient synthesis of 4-trifluoromethyl-substituted imidazole derivatives.
Mesoionic 4-trifluoroacetyl-1,3-oxazolium-5-olates (1), obtained from the reaction of N-acyl-N-alkylglycines (2) with trifluoroacetic anhydride, react with ammonia to give 4-trifluoromethyl-3,4-dihydroimidazoles (3) in high yields. Dehydration of 3 gives 4-trifluoromethylimidazoles (4) in high yields. The novel ring transformation of 1 into 3 occurs via a regioselective attack of ammonia on the...
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ورودعنوان ژورنال:
- Chemical & pharmaceutical bulletin
دوره 48 3 شماره
صفحات -
تاریخ انتشار 2000