Trifluoromethanesulfonylimides of arenehydroxamic acids and their aza Lossen rearrangement

Trifluoromethanesulfonylimides of arenehydroxamic acids ArC(NSO2CF3)NHOH (1), analogues of arenehydroxamic acids, in which sp2 hybridized oxygen atom is replaced by the much stronger electron-withdrawing group NSO2CF3, have been synthesized, and the abilities of these compounds to undergo transformations similar to the Lossen rearrangement have been studied.At heating O-trimethylsilyl or O-tosyl derivatives of acids 1 rearrange to carbodiimides ArNCNSO2CF3 or products of their hydration, the corresponding carbamides. Interaction of acids 1 with sulfinyl chloride or phosphorus pentachloride results in formation of N-trifluoromethylsulfonyl-N′-arenechloroformamidines, ArNHC(Cl)NSO2CF3, which were transformed into their morpholine derivatives and thus characterized.

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