Synthesis Of Sulfur-contanining Heterocyclic Compounds And Palladium-catalyzed C-S Bond Coupling Reaction

Sulfur-containing organic compounds show more and more wide application in Medicine, pesticide, biological, organic functional materials, etc. As many other important sulfur-containing organic compounds, Heterocyclic sulfides and thiothersare of great importance in many biological and medical reactive molecules or organic synthesis intermediates, when it was substitutedby various functional group.This dissertation mainly focused on the following two parts:(1)A new simple and efficient method to construct ring-fused 4-alkyl-4H-3,1-benzothiazine-2-thione derivatives has been developedfrom carbon disulfide and(E)-3-(2-aminoaryl)acrylates or(E)-3-(2-aminoaryl)acrylonitriles under mild conditions, without theneed for a metal catalyst. The newly developed method tolerates a wide range of substrates in moderate to excellent yields. Moreover,this method is advantageous over previous ones for the easy synthesis of reactants.(2)A palladium-catalyzed β-thioetherification of unactivated C(sp3)-H bond of 2-pyridine amides derivatives is established with the assistance of benzoquinone and silver carbonateauxiliary, leading to the β-thio 2-pyridine amides derivatives. The present method offered a new simple route to substituted thioethers via C-H bond activation in moderate yield, although the efficiency is not very good, so we need to optimize the reaction conditions in the future.