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As carbon-carbon bonds are an essential bond type in Nature, reactions that form C-C bonds are of great interest in organic chemistry. Among the most popular C-C bond formation methods with aromatic systems are palladium-catalyzed coupling reactions, such as the Heck, Suzuki, Negishi and Stille reactions. Even though these methods are efficient, they produce stoichiometric amounts of high molecular weight byproducts, placing them in conflict with the increasingly important ideas of sustainable reactions and green chemistry. In contrast, palladium-catalyzed desulfinative coupling reactions produce minimal waste; in general, only hydrogen halides or alkali halides are formed as byproducts in addition to SO2 gas, which can potentially be recycled. This microreview provides a brief historic overview on palladium-catalyzed coupling reactions with organosulfur compounds, with the main focus on the use of sulfinate salts as nucleophilic or electrophilic reaction partners. Various methods to access the sulfinate salts, and the coupling reactions of sulfonyl precursors that proceed through sulfinic acid/salt intermediates generated in situ are also discussed. [ABSTRACT FROM AUTHOR]

A range of aryl sulfinates can be oxidatively dimerized to generate substituted biphenyls with concomitant extrusion of sulfur dioxide with a palladium catalyst. Catalytic amounts of TEMPO and excess oxygen are utilized as oxidants to regenerate the palladium catalyst. [ABSTRACT FROM AUTHOR]

A ligand-free Pd-catalyzed cross-coupling of aryl sulfinates with aryl bromides has been developed. A variety of aryl bromides and aryl sulfinates undergo this transformation to yield the desired biaryl in a practical and economical manner. [ABSTRACT FROM AUTHOR]

Herein is described the full scope of a desulfinylative cross-coupling of aryl sulfinates with aryl bromides. Optimized conditions were established and a bidentate phosphine ligand was found to be the key in obtaining good cross-coupling yields. Preliminary efforts to elucidate the reaction mechanism suggest that a Pd(0)-catalyzed mechanism is operative. [ABSTRACT FROM AUTHOR]