Synthesis Of Metal Complexes With Bulky Silyl Linked-bis(Amidinate) Ligands And Their Applications In Catalytic Ethylene Polymerization

First reported by Gerhardt in1858, amidines have been widely investigated since then. In the past few decades, the non-cyclopentadienyl catalyst has attracted many organometallic chemist’s attention, especially the metal amidinate complexes become one of the hot topics in searching for non-cyclopentadienyl ligand.The main research work of this dissertation focuses on the characterization and synthesis of novel organometallic complexes incorporated with the silyl-linked bis(amidinate) ligands, some of them were tested for the polymerization of ethylene.Chapter1. A background for the topic of this thesis is summarized, including:(1) structures and characterization of amidines;(2) reserch developments of metal amidinates;(3) the synthesis and catalytic applications of amidinate metal complexes;(4) the aim and significance of the research work are introduced.Chapter2. The compounds2a、3a、4a、5a、6a(Scheme1)were synthesized by the reactions of a with AlCl3,MnCl2,FeCl2,CoCl2, which was characterized by X-ray diffraction crystallography. The amidine7a was synthesis by compound with water, and was characterized by X-ray diffraction.Chapter3. The reactions of b, c with the group IV metal dichloride gave a group of metal compounds2b,3b,2c,3c(Scheme3). They were characterized by X-ray diffraction crystallography and employed as catalysts in the polymerization of ethylene.Finally, the research contents are summarized and the potential applications for the silyl-linked bis(amidinate) metal complexs as catalysts toward ethylene polymerization and ring-opening polymerization (ROP) of lactone are proposed.