Synthesis, Structures Of Guanidinate And Triazapentadienyl Complexes

The research work in the thesis is based on the novel ligands containing nitrogen. Ten novel complexes were synthesed by using aniline or its derevative 2, 6- diisopropylaniline as starting materials via the reaction to cyanoamines free-fromα-hrdrogen. The major contents include the syhtheses and structural studies of novel 1, 3-diazaallyl metal complexes and 1,3,5-triazapentadienyl complexes. All the complexes here were chatacterized by ¹H-NMR, ¹³C NMR, elemental analysis and single crystal X-ray diffraction.Chapter one introduces in detail the background and the significance of the research. The following four parts were included: introduction; development, structural features and synthesis of 1, 3, 5-triazapentadienyl complexes; brief introduction and synthetic method of guanidinates; the applications and outlooks of guanidinates.Chapter two discusses the synthesis and structures of the novel 1,3,5-triazapentadienyl complexes 1a and 1b (Scheme 1) from the reaction of ligand PhN(Li)SiMe₃ (L¹)with carbonatriles free-fromα-hrdrogen at the ratio of 1:1. Their structures were chracterised by ¹H-NMR, ¹³C NMR, elemental analysis and single crystal X-ray diffraction. The steric effects of the substitutes in the carbonitrile on the structures were investigated. A lanthanide 1,3,5-triazapentadienyl complex was prepared for the first time.Chapter three discusses the synthesis and structures of a series of novel 2,4-disubstituted-1,3,5-triazapentadienyl complexes prepared via the reactions of the ligand (Dipp)N(Li)SiMe₃ (Dipp = 2,6- ⁱPr₂-C₆H₃) (L²) with carbonatriles free-from a-hrdrogen at the ratio of 1:2(including Mn, Fe, Co, Ni, Cu complexes, Scheme 2 and Scheme 3). The structures of 2a-2g were characterized by ¹H-NMR, ¹³C NMR, elemental analysis and single crystal X-ray diffraction. The influences of the central metal on the structures were studied.Chapter four involves a new method for 3,5-Disubstituted-1,2,4- triazole complex. This kind of compounds can be easily prepared via the reaction of PhN(Li)SiMe₃ (L¹)with carbonatriles free-fromα-hrdrogen at the ratio of 1:2, using CuCl)2 as catalyst. This method is simple and environmentally friendly. The proposed pathway for the formation of the complex is underway.Scheme 1 Reagents and conditions: i Me₂CN, Et₂O, ca. -78℃; ii YCl₃, THF/Hex, ca. -78℃; iii Bu^tCN, Et₂O, ca. -78℃; iv Me₂CN, Et₂O, ca. -78℃; TMEDAScheme 2 Reagents and conditions: i 2Me₂CN, Et₂O, ca. -78℃; ii MnCl₂, Et₂O, ca. -78℃; iii FeCl₂, Et₂O, ca. -78℃; iv CoCl₂, Et₂O, ca. -78℃; v NiCl₂ . 6H₂O, Et₂O, ca. -78℃. Scheme 3 Reagents and conditions: i 2Me₂CN, Et₂O, ca. -78℃; ii H₂O, r.t., ca. 25℃; iii CuCl/PPh₃, Et₂O, ca. -78℃; CH₂Cl₂(in N₂); iv CuCl, Et₂O, ca. -78℃; CH₂Cl₂(in air).Scheme 4 Reagents and conditions: i 2Me₂CN, Et₂O, ca. -78℃; ii CuCl₂, Et₂O, ca. -78℃.