Studies On Synthesis And Catalytic Reactivity Of Group-â…£ And Rare Earth Metal Complexes Incorporating Pyrrolyl Ligands

The thesis mainly focused on the synthesis and catalytic reactivity of group-IV and rare earth metal complexes incorporating pyrrolyl ligands. It's composed of following three parts.Firstly, six pyrrolyl schiff base ligands, L1, L2, L3, L4, L5 and L6 (L1=(E)-N-((1H-pyrrol-2-yl)methylene)pyridin-2-amine, L2=(E)-N-((1H-pyrrol-2-yl) methylene)(pyridin-2-yl)methanamine, L3=(E)-N-((1H-pyrrol-2-yl)methylene)-2-(py -ridin-2-yl) ethanamine; L4=(E)-N-((1H-pyrrol-2-yl)methylene)benzenamine, L5= (E)-N-((1H-pyrrol-2-yl)methylene)(phenyl)methanamine, L6=(E)-N-((1H- pyrrol-2-yl) methylene)-2-phenylethanamine), were designed and six new complexes of composition (NMe2)2Ti(N(C(Pyrrole)HC(Py)H)2N)Ti(NMe2)2?C7H8(1), Ti(L4)(NMe2)3(2), Ti(L5)2 (NMe2)2(3), Ti(L5)(NMe2)2 (4), Ti(L3)(NMe2)3 (5), (Ti(L6)2(NMe2)2)2(THF) (6) were synthesized. The crystal structures of complexes 1-4 were determined by X-ray diffraction, 1H NMR spectroscopy and elemental analysis. The complexes 5 and 6 were characterized by 1H NMR spectroscopy. Dinuclear titanium complex 1 was formed by the ring closing of the ligand L2. Complexes 2-6 are mononuclear titanium complexes incorporating pyrrolyl ligands. In addition, we proposed the formation mechanism of compound 1 and found that compounds 1-4 can be used as catalyst in the alkyne hydroamination reaction.Secondly, a tridentate ligand L7 (L7=N,N-Di(pyrrolyl-α-methyl)-N- methylamine), a quadridentate ligand L8 (L8=Tris((1H-pyrrol-2-yl)methyl)amine) and a heptadentate Schiff-base ligand L9 (L9=[((pyrrol-2-ylmethylidene)amino)ethyl]amine) were syn- thesized. Reaction of DyCl3 with two equivalents of NaN(SiMe3)2 in THF yielded complex (Dy(μ-Cl)(N(SiMe3)2)2 (THF))2 (7). X-ray crystal structure analysis revealed that 7 is a centrosymmetric dimer with asymmetrically bridging chloride ligands. Treatment of L7 with complex 7 and known compound (Yb(μ-Cl)(N(SiMe3)2)2(THF))2, respectively, led to the formations of complex (Dy(μ-Cl)(L7)2(THF)2)2 (8) and complex (Yb(μ-Cl)(L7)2 (THF)2)2 (9). Structure determination indicated that 8 and 9 exhibit as centrosymmetric dimmers with asymmetrically bridging chloride ligands. Treatment of L8 with Ln[N(SiMe3)2]3 (Ln=Sc, Sm, Dy) led to the formations of complexes Sc(L8)(THF)2 (10), Sm(L8)(THF)3 (11) and Dy(L8)(THF)3 (12). Reaction of L9 with Sc[N(SiMe3)2]3 yielded complex Sc(L9) (13). Complexes 10-13 are all mono-ligand coordinated rare earth complexes. The structures of complexes 7-13 were determined by X-ray diffraction and elemental analysis.Thirdly, the complex (NMe2)2Ti(L10)2Sm(THF) (14) (L10=N1,N3-[bis(pyrrole-2 -yl)methylene]diethylenetriamine), which is the first Titanium-Samarium heterometallic complex incorporating pyrrolyl ligand, was synthesized. The crystal structure of complex 14 was determined by X-ray diffraction and elemental analysis. The catalytic activity of 14 to the alkyne hydroamination reaction was also investigated.