Rhodium(iii)-catalyzed three-component cascade synthesis of 6H-benzo[c]chromenes through C-H activation

A three-component cascade reaction is described that provides concise access to 6H-benzo[c]chromenes via Rh(iii)-catalyzed annulation of aryl ketone O-acyloximes, quinones and acetone. Acetone acts as a co-solvent and as a reactant. This reaction shows high efficiency, atom- and step-economy, good substrate scope, excellent functional group compatibility and gives the products in good yields.

RhIII-Catalyzed Synthesis of Isoquinolones and 2-Pyridones via Annulation of N-Methoxyamides and Nitroalkenes

The Rh(III)-catalyzed synthesis of 4-substituted isoquinolones and 2-pyridones by the annulation of N-methoxyamides and nitroalkenes has been developed. Both aliphatic and aromatic nitroalkenes were effective inputs. Annulations also proceeded for aromatic, alkenyl, and heteroaromatic C-H bond starting materials. Moreover, benzoic acid provided a novel nitrodihydroisocoumarin. The structure and relative stereochemistry of this compound, which is an oil at room temperature, was determined unambiguously by single crystal X-ray diffraction of its inclusion complex with a hydrogen-bonded host framework.

Rhodium(III)-Catalyzed Imidoyl C-H Activation for Annulations to Azolopyrimidines

Azolopyrimidines are efficiently prepared by direct imidoyl C-H bond activation. Annulations of N-azolo imines with sulfoxonium ylides and diazoketones under redox-neutral conditions and alkynes under oxidizing conditions provide products with various arrangements of nitrogen atoms and carbon substituents. We have also probed the mechanism of this first example of Rh(III)-catalyzed direct imidoyl C-H activation by structural characterization of a catalytically competent rhodacycle obtained after C-H activation and by kinetic isotope effects.

Rhodium(III)-catalyzed C-H functionalization of C-alkenyl azoles with sulfoxonium ylides for the synthesis of bridgehead N-fused [5,6]-bicyclic heterocycles

The synthesis of bridgehead N-fused [5,6]-bicyclic heterocycles via rhodium(III)-catalyzed C-H functionalization of C-alkenyl azoles with sulfoxonium ylides is disclosed. Reactions proceeded in good to high yields for a range of aryl, heteroaryl and alkyl sulfoxonium ylides. In addition, 2-alkenyl imidazoles with different substitution patterns as well as C-alkenyl triazoles were effective inputs. The reaction could also be performed under straightforward bench top conditions.

Rhodium(iii)-catalyzed annulative coupling between arenes and sulfoxonium ylides via C–H activation

Sulfoxonium ylides acts as a bifunctional C₂-synthon in Rh(iii)-catalyzed redox-neutral annulative coupling with arenes for the synthesis of N-heterocycles and carbocycles.

Facile construction of hydrogenated azepino[3,2,1-hi]indoles by Rh(iii)-catalyzed C–H activation/[5 + 2] annulation of N-cyanoacetylindolines with sulfoxonium ylides

Rh(iii)-catalyzed regio- and chemoselective [5 + 2] annulation has been realized, leading to efficient construction of seven-membered rings under mild conditions.

Cp*Rh(iii)-catalyzed annulation of N-methoxybenzamide with 1,4,2-bisoxazol-5-one toward 2-aryl quinazolin-4(3H)-one derivatives

A [Cp*Rh^III]-catalyzed annulation of N-methoxybenzamide with 1,4,2-bisoxazol-5-one was developed, affording a series of 2-aryl quinazolin-4(3H)-one derivatives.