Studies On Titanium And Zirconium Complexes Supported By Nitrogen-containing Heterocycles And Their Catalytic Behaviors Towards Intermolecular Hydroamination, ROP Of ε-caprolactone And Dimerization Of Ethylene

The thesis is mainly focused on the syntheses of titanium complexes and their catalytic behaviors towards hydroamination, ROP of ε-caprolactone and dimerization of olefin. It is composed of three parts.Firstly, two indolyl-containing ligands HL1(HL1 = 2-pyrazol-1-yl-1H-indole) and HL2(HL2 = 2-[1,2,4]triazol-1-yl-1H-indole) and three novel titanium complexes Ti(L1)2(NMe2)2(1), Ti(L2)2(NMe2)2(2) and Zr(L1)2(NMe2)2(3) were synthesized. All complexes have been characterized by NMR measurement and elemental analyses as well as the single crystal Xray diffraction of 1 and 2. Both 1 and 2 exhibited high activities towards intermolecular hydroamination of terminal alkynes with high selectivity.Secondly, two new titanium complexes Ti(L1)2Cl2?THF(4?THF) and Ti(L2)2Cl2?THF(5?THF) have been synthesized. The two complexes have been characterized by elemental analyses and NMR studies. The catalytic activity of 1 and 2 to the ring-opening polymerization of ε-caprolactone was investigated. 4?THF and 5?THF efficiently initiated the dimerization of ethylene.Lastly, two new ligands incorporating pyrrolyl ring H2L3(H2L3 = 2-[(1H-Pyrrol-2-ylmethylene)-amino]-phenol) and H2L4(H2L4 = N,N’-Bis-(1H- pyrrol-2-ylmethylene)-benzene-1,2-diamine) were synthesized. Then, two novel complexes Ti2(L3)2(NMe2)8(6) and Ti(NBut)(L4)Py2(7) were prepared. The crystal structures of 6 and 7 were confirmed by X-ray diffraction.