Research On Cross-Coupling Reactions Of Sulfinic Acid Derivatives

Sulfinic acid derivatives are widely applied in various fields such as organic chemistry, pharmaceutical chemistry, biological chemistry, and agricultural chemistry. They are employed to synthesize drugs, pesticides, bioactive intermediates and functional materials. Sulfinic acid derivatives are cheap, commercially available, easy-handle and bench-stable. Recently, the cross-coupling reactions based on sulfinic acid derivatives are growing rapidly. First, sulfinic acid derivatives have the potential to serve as the aryl sources for the constructions of C-C bond and C-heteroatom bond. Second, sulfinic acid derivatives can be used to synthesize sulfones and sulfides via constructing C-S bond and S-heteroatom bond. With the development of green and sustainable chemistry, designing new organic reactions with excellent yields and selectivities under mild conditions is a main topic in modern organic chemistry. The main topic of this paper is the research of cross-coupling reactions based on sulfinic acid derivatives. The coupling reactions with aromatic sulfinic acid sodium salts and arylhydrazides are developed. The detail works are described as follows:1. A palladium-catalyzed approach for the synthesis of diarylmethanes via desulfitative benzylation of aromatic sulfinic acid sodium salts with benzyl chlorides has been demonstrated. The reaction showed good selectivity and tolerated various functional groups. This new method provides an economic and efficient route for the synthesis of diarylmethanes from benzyl chlorides.2. A novel sodium sulfinate-mediated intermolecular elimination of benzylic halides under transition metal-free conditions is developed. Various symmetrical and non-symmetrical stilbene derivatives were selectively obtained from benzylic halides in good yields. The sodium sulfinate played an important role in this transformation.3. A novel approach for the synthesis of N-arylsulfonamides from nitroarenes and arylsulfonyl hydrazides under palladium-catalysis conditions is described. Nitroarenes were reduced in situ by hydrogen released from arylsulfonyl hydrazides and no external reducing agent is necessary. This method affords an efficient approach using readily available and stable nitroarenes for facile construction of N-arylsulfonamides under mild reaction conditions with good selectivity.