Considering the importance of the chiral allylic amine structural motif and the rarity of synthetic methods toward their construction, herein, we report a Cp X Rh(III)-catalyzed enantioselective intermolecular carboamination of 1,3-dienes via N-phenoxy amides-derived intermolecular aryl C−H activation and intramolecular amide transfer. The methodology enables the direct synthesis of a variety of chiral allylic amines with the embedment of phenol functionalities and proceeds under mild conditions with sequential formation of a completely regioselective C−C bond and a highly enantioselective C−N bond. Integrated experimental and computational mechanistic studies reveal an unusual Rh(III)− Rh(I)−Rh(III) catalytic pathway, in which an alkene insertion/π-allylation/intramolecular nucleophilic substitution cascade was involved for this transformation. Besides, synthetic application in the derivation of natural products and the late-stage assembly of bioactive complexes has also been demonstrated, which further strengthens the synthetic utility of this approach.

By making use of a direct C–H activation strategy, an efficient osmium­(II)-catalyzed redox-neutral [4 + 2] annulation of N-methoxybenzamides with alkynes has been accomplished. Computational and experimental studies revealed that such transformation leading to the synthesis of the isoquinolone core might follow an Os­(II)–Os­(IV)–Os­(II) catalytic pathway, in which an unusual HOAc-assisted oxidative addition of osmium­(II) into the N–O bond to generate the osmium­(IV) species was involved as one of the key transition states. Further exploration of divergent C–H activation reaction modes enabled by the osmium­(II) catalyst has also been exemplified for one-pot assembly of other either linear or cyclic products.

A unique Rh­(III)-catalyzed C–H activation/[3 + 2] annulation of N-phenoxyacetamides has been developed for the construction of dihydrobenzofurans via carbooxygenation of 1,3-dienes. This transformation features a redox-neutral process with specific chemoselectivity, good substrate/functional group compatibility, and profound synthetic potentials. A preliminary exploration to realize their asymmetric synthesis have been also successfully demonstrated, which further strengthens the practicality of this approach.