Copper-catalyzed three-component reactions of 2-iodoanilines, benzylamines, and sulfur powder are reported to afford benzothiazoles in a simple one-pot procedure by using water as solvent. A variety of 2-arylbenzothiazoles were obtained in moderate to good yields up to 88%.

Palladium-catalyzed dehydrogenative coupling reactions between acetanilides and benzylic alcohols under aqueous conditions are reported. A wide range of benzophenone derivatives could be obtained in good to excellent yields up to 98 %. Mechanism studies showed that a bimetallic palladium cyclopalladated complex might be involved in the catalysis.

Palladium-catalyzed dual CH functionalization of diaryl sulfides to form dibenzothiophenes (DBTs) by oxidative dehydrogenative cyclization is reported. This protocol afforded various DBTs in moderate to good yields with tolerance of a wide variety of substrates. Benzo[1,2-b:4,5-b′]bis[b]benzothiophene was successfully synthesized by this method, which was used as an organic semiconductor for field-effect transistors.

Three-component reactions involving amines, aldehydes, and elemental sulfur powder are reported to afford thioamides in a simple one-pot procedure in the absence of a catalyst. A variety of thioamides can be obtained in good to excellent yields up to 88 %.

The cuprous complex – Cu₄I₄(H₂O)₄ – has been isolated and employed for the catalytic hydrolysis of arenecarbonitriles, cinnamonitrile, and arylacetonitriles to the corresponding amides in pure water in high yields of up to 98%. The catalyst can be easily recovered and reused without loss of catalytic activity at least five times. Oxindole could be prepared successfully by one-pot domino protocols based on this method.

An unusual copper-catalyzed cyanation of aryl iodides to form aryl nitriles by cyano group transfer from C(sp³) to C(sp²) carbon atoms is reported and proceeds to give yields of up to 86%.

A simple and efficient method for the preparation ofpyrido[1,2-a]benzimidazoles by a copper-catalyzed inter- and intramolecular C–N coupling cascade process was designed and carried out, and the products were obtained in moderate to excellent yields (up to 93 %).

A water-soluble sulfonato-Cu(salen) complex catalyzed procedure for the N-arylation of simple aliphatic amines, amino alcohols and amino acids in pure water have been developed. A variety of substituted aryl iodides, bromides and electron-deficient chlorides were found to be applicable, and 1,2-disubstituted benzimidazoles could be prepared easily by a cascade amination/condensation process in this catalytic system.

The cross-coupling reaction between aryl halides andaqueous ammonia was efficiently catalyzed by the sulfonato–Cu(salen) complex in water with high yields. A variety of substituted aryl bromides and aryl iodides were found to be applicable to the environmentally benign system. Substituted 1H-benzimidazole could also be easily prepared by coupling aqueous ammonia with 2-iodoacetanilide in one pot with this catalytic system.