Facile generation and isolation of φ-allyl complexes from aliphatic alkenes and an electron-deficient rh(III) complex: Key intermediates of allylic c-h functionalization

It has been established that a strongly electrophilic ?⁵-cyclopentadienylrhodium complex, [Cp^ERhCl₂]_2, is capable of reacting with aliphatic alkenes in the presence of a silver salt and cesium acetate at room temperature to give the corresponding ?-allyl complexes in high yields. The use of an alkenyltosylamide as the alkene also afforded the corresponding ?-allyl complex. Treatment of the thus obtained ?-allyl complex with a silver(I) salt and copper(II) acetate afforded the allylic amination product, which proves the intermediacy of this ?-allyl complex in the rhodium(III)-catalyzed intramolecular oxidative allylic amination.