Synthesis And Structures Of 1,3,5-Trizapentadienato Complexes Having Guanidinato Moieties

In the research work, we studied on the addition reactions of PhN(Li) SiMe3 with 2 equiv of differentα-hydrogen-free carbonitriles, which led to in stiu synthesis of 1,3,5-triazapentadienato ligands [PhNC(R')NC(R')NR]-(R= SiMe3, R'=NMe2,1-piperidino) and further to their derived metal complexes. Five novel metal complexes were synthesized and their structures were characterized by single crystal X-ray diffraction,1H NMR,13C NMR and elemental analysis. The details included the following three chapters.Chapter 1. The significance and background of the research were introduced in detail. It is divided into three sections:(1) the introduction of organometallic chemistry; (2) the developments and applications of guanidinates; (3) synthesis and structures of 1,3,5-triazapentadienato ligands and their derived metal complexes.Chapter 2. The reaction of reagent PhN(Li)SiMe3(L) withα-hydrogen-free 1-piperidinecarbonitrile at the ratio of 1:2 led to 1,3,5-triazapentadienato ligands and further to their derived transition-metal complexes 2a and 2b (Scheme 1). Their structures were characterized by single crystal X-ray diffraction,1H NMR,13C NMR and elemental analysis. Scheme 1 Synthesis of complex 2a and 2b Reagents and congditions:ⅰ2 1-piperidinecarbonitrile, Et2O, ca,-78℃; 1/2FeCl2, Et2O, ca,-78℃.ⅱ2 1-piperidinecarbonitrile, Et2O, ca,-78℃; 1/2CoCl2, Et2O, ca,-78℃.Chapter 3. The reactivity of reagent PhN(Li)SiMe3(L) withα-hydrogen-free nitrile (Me2NCN,1-piperidinecarbonitrile) at the ratio of 1:2 was studied, and from which the 1,3,5-triazapentadienato ligands were obtained. The ligands reacted with SnCl2·2H2O can give 3a, while with SnCl2 lead to 3b and 3c (Scheme 2). Their structures were characterized by single crystal X-ray diffraction,1H NMR,13C NMR and elemental analysis. Their structural features were analylized and compared with each other.Scheme 2 Synthesis of complex 3a-3c Reagents and conditions:ⅰ2 Me2NCN, Et2O, ca,-78℃; SnCl2.2H2O, Et2O, ca,-78℃.ⅱ2 Me2NCN, Et2O, ca,-78℃; 1/2SnCl2, Et2O, ca,-78℃.ⅲ2 1-piperidinecarbonitrile, Et2O, ca,-78℃; 1/2SnCl2, Et2O, ca,-78℃.