Studies On Base-Catalyzed Reactions Of Cyano-Migrate

The cleavage of carbon-carbonσ-bonds by transition-metal complexes and their use for chemical transformation would provide a conceptually new strategy in organic synthesis. However ,the inherent stability of carbon-carbonσ-bonds makes the development of such a process a daunting challenge. Although some success has been attained to this end, it has usually required the utilization of strained carbon-carbon bonds or chelation-assisted systems. This limitation is absent in the transition-metal-mediated cleavage of carbon-carbonσ-bonds in nitriles, in which the strong carbon-carbon(C-CN) bond (ca.130 kcal/mol for Ar-CN) can be cleaved without the aid of ring strain or extra coordinating groups. Fundamental interest in this unique process has prompted organometallic chemists to identify two discrete mechanisms for the activation of C-CN bonds. One process involves the oxidative addition to a low-valent metal center, such as Pt, Pd , Ni, and others. The other process involves the deinsertion of silyl isocyanide.Recently, we found that cleavage and addition reaction of C-CN bonds across alkynes on the condition of weak base(K2CO3) takes place effectively to give various substituted alkenenitriles. In this pieces, we consider mainly about the cleavage C-CN bonds on the condition of weak base and the reaction mechanism.In this thesis, many new compounds were synthesized and characterized by mass and NMR(1H, 13C) spectrum.