Multisubstituted isoquinoline and pyridine N-oxides have been prepared by Rh(III)-catalyzed cyclization of oximes and diazo compounds via aryl and vinylic C-H activation. This intermolecular annulation involving tandem C-H activation, cyclization, and condensation steps proceeds under mild conditions, obviates the need for oxidants, releases N2 and H2O as the byproducts, and displays a broad substituent scope.

The first Rh(I)-catalyzed asymmetric approach for the intermolecular functionalization of C(sp 3 )−H bonds is reported. For the first time, unsymmetrical N-heterocyclic carbenes (NHCs) were used for asymmetric catalysis that is capable of achieving not only high site-selectivity but also enantioselectivity. The Rh(I)/NHC* catalytic systems were applied to asymmetric direct C(sp 3 )−H arylation, which provides a synthetic route toward enantioenriched triarylmethanes.

Efficient Rh(III)-catalyzed C-H activation of different classes of (hetero)arenes such as 2-phenylpyridine, indoles, aryl ketones and acetanilide and their dehydrogenative cross-coupling with allylic alcohols are described. Several important skeletons such as β-aryl aldehydes and ketones, 2-acetylindenes, 3,4-dihydro-1H-quinolin-2-one and quinoline could be produced using this protocol.

Biologically interesting fused oligocyclic lactams have been prepared via an intramolecular redox-neutral cyclization process. By the proper choice of the substrates with a wide variety of tethered olefins, the less favored C-H bond can be activated and functionalized. This C-H activation proceeds under mild conditions, obviates the need for external oxidants, and displays a broad scope with respect to the substituents.

In this communication we report a new strategy toward ketopyranosides based on a carbene-mediated activation of the anomeric C-H bond of carbohydrates. By forming a new carbon-carbon bond after a glycosylation step, this approach enables the preparation of both α- and β-ketopyranosides from advanced precursors.