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A valuable palladium-catalyzed three-component coupling reaction for the synthesis of amidines has been developed. Using arylboronic acids, isocyanides, and anilines as the reactants under oxidative conditions, various amidines were isolated in good yields with good functional group tolerances.

Carbonylation reactions are a most powerful method for the synthesis of carbonyl-containing compounds. However, most known carbonylation procedures still require noble-metal catalysts and the use of activated compounds and good nucleophiles as substrates. Herein, we developed a copper-catalyzed carbonylative transformation of cycloalkanes and amides. Imides were prepared in good yields by carbonylation of a C(sp3)−H bond of the cycloalkane with the amides acting as weak nucleophiles. Notably, this is the first report of copper-catalyzed carbonylative C−H activation.

The palladium-catalyzed Suzuki cross-coupling of phenylhydrazine or (phenylsulfonyl)hydrazine was developed for the preparation of biaryl compound in high yields. Moreover, these hydrazines were also used in other cross-coupling reactions, and a possible pathway of this reaction was examined.

A series of 2-heteroaryl-substituted pyridine N-oxides (III) is prepared by palladium-catalyzed oxidative cross-coupling of N-oxides (I) with corresponding heteroarenes (26 examples).

The direct arylation of electron-deficient heterocycles, such as (I), (V), (VIII), and (X) with arylhydrazine hydrochlorides (II) without any catalyst and co-oxidant is described.

The highly efficient and regioselective oxidation represents a practical preparation of unsymmetrical and symmetrical bisheteroaryl molecules.

An efficient route for the synthesis of 2,4-disubstituted 1,2,3-triazoles by the regioselective direct arylation of 2-aryl-1,2,3-triazole N-oxides with Ar–X [X = Br, I and B(OH)2] is demonstrated. The reaction proceeds through Pd-catalyzed C–H bond activation, and the influence of the aryl halides on the reactivity is investigated.

Two highly efficient protocols for the regioselective synthesis of 2-substituted 4-alkenyl- and 4-aryl-1,2,3-triazoles by the palladium-catalyzed C–H functionalization of 1,2,3-triazole N-oxides are reported. A possible pathway of direct alkenylation with 1-octene and vinyl acetate is discussed.