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A simple and general copper-catalyzed method has been developed for transformations of various functional groups (-I, -N(3), -SO(2)R, -OH, -NH(2), and -NO(2)) on aromatic rings from arylboronic acids in water under air. The protocol uses cheap and readily available inorganic salts (KI, NaN(3), NaSO(2)R, NaOH, NaNO(2)) and aqueous ammonia as the functional-group sources, simple Cu(2)O/NH(3) as the catalyst system, environmentally friendly water as the solvent, and oxygen in air as the oxidant. Importantly, the copper catalyst system in water was recyclable. This study should provide a useful strategy for interconversions of the functional groups on aromatic rings.

Efficient and practical visible-light photoredox borylation of aryl halides and subsequent aerobic oxidative hydroxylation were developed. The protocols use readily available aryl halides and bis(pinacolato)diboron as the starting materials, fac-Ir(ppy) as the photocatalyst, and corresponding arylboronic esters and phenols were obtained in good yields. The methods show some advantages including simple equipment, mild conditions, easy operation, and wide substrate scope. Therefore, they should provide a valuable strategy for chemical transformations.

The formation of aryl C-S bonds is an important chemical transformation because aryl sulfides are valuable building blocks for the synthesis of biologically and pharmaceutically active molecules and organic materials. Aryl sulfides have traditionally been synthesized through the transition-metal-catalyzed cross-coupling of aryl halides with thiols. However, the aryl halides used are usually bromides and iodides; readily available, low-cost aryl chlorides often not reactive enough. Furthermore, the deactivation of transition-metal catalysts by thiols has forced chemists to use high catalyst loadings, specially designed ligands, high temperatures, and/or strong bases, thus leading to high costs and the incompatibility of some functional groups. Herein, we describe a simple and efficient visible-light photoredox arylation of thiols with aryl halides at room temperature. More importantly, various aryl chlorides are also effective arylation reagents under the present conditions.