Palladium-Catalyzed Intramolecular Cross-Coupling of Unactivated C(sp3)-H and C(sp2)-H Bonds.

Direct C-H/C-H coupling represents an appealing method for the construction of C-C bonds, and the cross-coupling of unactivated C(sp3)-H and C(sp2)-H bonds is challenging and remains to be investigated. We have developed the Pd-catalyzed intramolecular coupling of inert C(sp3)-H and C(sp2)-H bonds. The reaction proceeded by o-methyl oxime-directed aryl C(sp2)-H activation and subsequent alkyl C(sp3)-H cleavage, generating C(sp2),C(sp3)-palladacycles as the key intermediates. Dihydrobenzofurans and indanes were formed as the final products.