Palladacycle-catalyzed Suzuki-miyaura Coupling Of MIDA Boronates And C-H Activation Reaction Of Heteroaryl Substituted Thiophenes

In this thesis, the catalytic activity of cyclopalladated ferrocenylimines andN,O-ligands palladacycle complex in C-C cross-coupling reactions had been studied.The main obtained results were as follows:1. An efficient and versatile protocol of cyclopalladatedferrocenylimines-catalyzed Suzuki-Miyaura reaction involving variousN-methyliminodiacetic acid (MIDA) boronates with aryl/heteroaryl halides had beendeveloped in EtOH/H2O or H2O. Typically, using triphenylphosphine adduct ofcyclopalladated ferrocenylimine as catalyst, a series of heteroaromatic compoundswere obtained in good to excellent yields in the presence of K3PO4as base inEtOH/H2O or H2O (20mol%TBAB) at90-100oC under nitrogen protection. Thereaction of aryl/heteroaryl chlorides with MIDA boronates could be carried out in thepresence of cyclopalladated ferrocenylimines (dimer) compounds and X-Phos (4mol%) at90oC in H2O to afford the target products in good to excellent yields.2. Using the thiophene products obtained in the Suzuki-Miyaura reaction, thecatalytic activity of N,O-ligands palladacycle complex in C-H arylation of thiopheneswith4-bromotoluene had been investigated. The direct C-H arylation ofaryl/heteroaryl thiophenes at the α-position could proceed in low catalyst loading of bis(alkoxo)palladium complex (0.1mol%) at100oC to give the correspondingproducts in good to excellent yields.