Studies On The Transition Metal-catalyzed Desulfitative Direct Arylation And Intramolecular Lactonization

Organosulfur compounds are an important kind of electrophilicreagents, which are ubiquitous in many natural products. In the last fewyears, much attention has been paid to the transition-metal-catalyzeddesulfitative C-C cross-coupling reactions using organosulfur compounds.The direct arylation of arenes and heteroarenes via cleavage of C-Hbonds has been the hot topic. Moreover, the reaction of esterification isalso a strong and powerful protocol to construct compound skeletons.This dissertation consists of two parts:In part one, the recent research progress on thetransition-metal-catalyzed desulfitative C-C cross-coupling reactions wasreviewed. In addition, a palladium-catalyzed desulfitative arylation ofbenzoxazoles C-H bonds was described, using sodium arenesulfinates asarylating reagents via the release of SO2. Moreover, benzothiazoles can also react with sodium arenesulfinates under the standard reactions.Above all, the preliminary mechanism was investigated.In part two, an efficient rhodium or palladium-catalyzed cascade aryladdition/intramolecular lactonization of phthaladehydonitrile witharylboronic acids to access3-aryl and alkenyl phthalides has beendeveloped, which tolerates a series of functional groups. Moreover, themechanism was studied and DFT calculations were carried out.