A FACILE PREPARATION OF N-(ISOPROPOXYALKYL) AMIDES BY GENERATION AND TRAPPING OF N-ACYLIMINIUM IONS FROM IONIZATION-REARRANGEMENT REACTIONSOF N-TRIFLYLOXY AMIDESE

A series of hydroxamic acids were converted to N-triflyloxy amides whi ch were heated in 2-propanol to give N-(1-isopropoxyalkyl) amides in h igh yields. The method is simple, direct, and extremely tolerant of st ructural diversity both in the N-acyl group, as well as in the 1-isopr opoxyalkyl group. N-Alkylation of secondary N-(1-isopropoxyalkyl) amid es can be used for converting them to tertiary N-(1-isopropoxyalkyl) a mides. N-Acyliminium ions of wide structural diversity can be generate d easily from N-(1-isopropoxyalkyl) amides available by this methodolo gy.