The Study Of The Oxidative Oxosulfonation And[3+2]cycloaddition Involving Olefins

After decades of development of transition metal palladium-catalyzed, organic synthesis technology was improved greatly. However, the concept of sustainable development and green chemistry was gradually known to all, it demanded modern chemists to develop a new green and efficient palladium-catalyzed coupling reaction.In traditional palladium-catalyzed coupling reaction, a large number of expensive ligands were used, which was not fit the demand of the new green efficient palladium-catalyzed coupling reaction. So, many chemists spared no effort to explore new type ligands to construct C-C bond and C-X bond. Nowadays, chemists paid more attention to carbonhydrate, such as sugar, which was a natural, non-poisonous and cheap ligand.This paper first summarized the organometallic chemistry, and the discovery and the development of organometallic compounds, and the development of the coupling reaction that transition metal palladium involved. And then, this paper introduced the development of the oxidantive coupling reaction involving olefins through the transition-metal palladium-catalyzed and the lively olefins in cyclization reaction, especially the application of the heterocyclic’s synthesis involving nitroolefin. This study includeed the following two results:(1) This paper had realized that with the palladium chloride as catalyst, pivalate copper as oxidant, a novel carbohydrates-involved aerobic oxidative oxosulfonation of olefines with DMSO has been developed, in which C-S, C-O, C-C, C-Br, C-COOH etc bonds cleavages were efficiently achieved. In this transform process, we detected phenol and cyclohexanol by GC-MS in order to speculate the form of the leaving-group. A diverse collection of valuable β-oxo sulfones were easily synthesized by this protocol. X-ray absorption experiments showed that the carbohydrates could reduce the copper(II) to copper(0) in neutral condition, which was different from the traditional Fehling reaction.(2) This paper had realized that a simple and efficient [3+2]cycloaddition reaction between N-iminoquinazolinium ylide and nitroolefins was developed. From a synthetic point of view, this protocol represents an efficient way to pyrazolo[1,5-c]quinazolines derivatives. The reaction condition was extremely simple, green without any additional additives. At the same time, the reactants was cheap andeasy-gotten, and the product was easy to be purified. This reaction is easy to be operated. From the perspective of organic synthetic methodology, the one step to construct various substituted pyrazole[1, 5-c]quinazoline possessed an important research significance and practical significance.