Palladium-catalyzed Oxidative Carbonyla- Tion Of Hydrazides:Synthesis Of 1,3,4-oxadiazol-2(3H)-ones

In 2010, R. Heck, A. Suzuki and E. Negishi were honored with Nobel Prize in Chemistry for their pioneer work in transition-metal-catalyzed reactions, which also represented the importance of these kind of reactions. Among all the transition-metal-catalyzed reactions, Pd-catalyzed reac-tion is especially important. As an important branch of Pd-catalyzed reaction, the carbonylation reaction has arouse great interest from scientists. Today, amounts of Palladium-catalyzed car-bonylation reactions are used in synthesis of medicine, pesticides, and functional materials. In this thesis, we aim to introduce a review of Pd-catalyzed carbonylation reactions and a new access to 1,3,4-oxadiazol-2(3H)-ones. The main body contains two parts.Firstly, we will summarized the Pd-catalyzed carbonylation reactions in existence. In this part, We will divided these reactions into two classes by the reaction conditions:base condition and oxidative condition. In the base condition, we will introduce in two way from the categories of R-X (X represents the leaving group). In the part of oxidative condition, the review will be intro-duced in C=O in N-H types carbonylation respectively.Secondly, we aim to a new method to synthesize 1,3,4-oxadiazol-2(3H)-ones. 1,3,4-oxadiazol-2(3H)-one core is an important scaffold found in medicinal chemistry, which is widely used as Hormone-sensitive lipase (HSL) inhibitions, herbicides, fungicides, and function tools in chemical science. In this case, we introduce a novel palladium-catalyzed oxidative car-bonylation reaction via the carbon monoxide insertions between amine group and carbonyl group to realize the intramolecular cyclization, which provides an efficient access to 1,3,4-oxadiazol-2(3H)-ones.