Studies On Synthesis Of (Z)-Vinyl Sulfides With High Regioselectivity

Vinyl sulfides are prevalent in many natural products and pharmaceuticals and are versatile intermediates for the synthesis of biologically active compounds, organic building blocks, and new materials. Three simple ways for synthesis of vinyl sulfides have been developed.First, A new method for synthesis of a series of vinyl sulfides formed in good-to-excellent yield with high regio- and stereoselectivity from mercaptobenzoic and terminal alkyne under transition-metal-free conditions was investigated.Z-anti-Markovnikov isomers were predominately formed under mild conditions.The system is applicable to a broad range of terminal alkynes with the highest yield85%.Second, the highest yields of anti-Markovnikov vinyl sulfides were achieved97% through hydrothiolation of terminal alkynes by 2,2’-dithiosalicylic acid with excellent regio- and stereoselectivity. Moreover, the detailed mechanism has been explored, the introduction of H2 O is found to play a very significant role in enhancing the stereoselectivity.Third, the process of a green methodology for synthesizing vinyl sulfides with perfect sregio- and stereoselectivity(Z:E>97:3) has been studied by utilizing water as solvent and inexpensive substrates(DTSA). It’s an important advantage compared to traditional methods based on organic solvent and expensive metal catalysts.