Convenient synthesis of 5-trifluoroacetylated imidazoles by ring transformation of mesoionic 1,3-oxazolium-5-olates.

نویسندگان

  • M Kawase
  • S Saito
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.

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عنوان ژورنال:
  • Chemical & pharmaceutical bulletin

دوره 48 3  شماره 

صفحات  -

تاریخ انتشار 2000