Research On Cross-coupling Reactions With Arylsulfonyl Compounds

The reagents commonly used in traditional coupling reactions are compounds with high reactivity and good selectivity such as organic halides,organic borides,sulfonates,organometallic reagents,etc.However,there are some problems with these reagents,such as perishable grimnard reagents,halides activity with too high or too low and expensive reagents,etc.Therefore,it is the natural mission of chemists to explore new coupling reagents.In recent decades,transition metal-catalyzed cross-coupling reactions have become a new hotspot in organic synthesis,and have become an important means to construct carbon-carbon bonds or carbon-hetero bonds.It is widely applied in synthesis,chemical production,medicine,agriculture,and dye industries and materials science,etc.It was found that arylsulfonyl compounds could participate in the coupling reaction through desulfurization process or reduction process,which provides a new direction for the development of new electrophilic coupling reagents.Based on the work of synthesizing 3,4-dihydropyrimidinethione and its derivatives by our group,this paper explored the coupling reactions of arylsulfonyl compounds with 3,4-dihydropyrimidinethione and 1,2-di?pyrimidin-2-yl?disulfides,and synthesized a series of C-C and C-S coupling products.The main contents are as follows:1.The advances in coupling reactions of arylsulfonyl compounds with various substrates were reviewed,such as alkenes,alkynes,?hetero?aromatic hydrocarbons and heterocyclic compounds,etc.2.The desulfurization coupling reaction of 3,4-dihydropyrimidinthiones and arylsulfonyl hydrazides was studied under the conditions of Pd?OAc?₂ as catalyst and Cu?OAc?₂ as oxidant,and thirty-three C-C coupling products were produced.Moreover,the structures of the target products were characterized by ¹H NMR,¹³C NMR and HRMS and the reaction mechanism was also studied in depth.The method was tolerant of pyrimidinethiones and other substrates bearing latent free-thiol functionalities.There was remarkable universality of the reaction.3.The C-S coupling reaction of 1,2-di?pyrimidin-2-yl?disulfides with arylsulfonyl chlorides was explored under Pd?OAc?₂.Fourteen corresponding C-S coupling products were synthesized.The structures of the products were confirmed by ¹H NMR,¹³C NMR and HRMS.The reaction was carried out without gas protection,but the scope of its substrates was limited.