An unexpected C-C bond cleavage has been observed on pentafluorobenzoylamidoxlmes under mild basic conditions. This observation has been exploited to develop a new synthesis of 1,2,4-oxadiazol-5-ones from amidoximes using pentafluorobenzoyl chloride or trifluoroacetic anhydride (TFAA) as a double acylating agent. The pentafluorophenyl anion and the trifluoromethyl anion acted as leaving groups in this transformation.
Christian Heinis, Edward Jeffrey Will, Anne Sofie Luise Zarda, Alexander Lund Nielsen, Sevan Mleh Habeshian, Mischa Schüttel, Gontran Sangouard