Palladium-Catalyzed Mizoroki-Heck Reaction of Nitroarenes and Styrene Derivatives.

We have developed a Mizoroki-Heck reaction of nitroarenes with alkenes under palladium catalysis. The use of a Pd/BrettPhos catalyst promoted the alkenylation, whereas other catalysts led to a decrease in the product yield. In addition to nitroarenes, nitroheteroarenes were also applicable to the present reaction. The combination of a nucleophilic aromatic substitution (SNAr) with the denitrative alkenylation produced a multifunctionalized arene in a one-pot operation.

Pd-Catalyzed Denitrative Intramolecular C-H Arylation.

A Pd-catalyzed intramolecular C-H arylation of nitroarenes has been developed. Nitroarenes bearing tethered aryl groups at the ortho-position can be readily prepared in one step from 2-halonitroarenes by a nucleophilic aromatic substitution (SNAr). Under Pd/BrettPhos catalysis, activations of the C-NO2 bond as well as the C-H bond on arenes generated the corresponding biaryl linkage in moderate to excellent yields.

Decarbonylative Methylation of Aromatic Esters by a Nickel Catalyst.

A Ni-catalyzed decarbonylative methylation of aromatic esters was achieved using methylaluminums as methylating agents. Dimethylaluminum chlorides uniquely worked as the methyl source. Because of the Lewis acidity of aluminum reagents, less reactive alkyl esters could also undergo the present methylation. By controlling the Lewis acidity of aluminum reagents, a chemoselective decarbonylative cross-coupling between alkyl esters and phenyl esters was successful.