Synthesis And Characterization Of Diazaphopholes-derived Bidentate Ligand(N,N’)and Palladium Complexes

Diazaphosphole is a kind of heterocyclic compounds containingN and P atom, it is of particular interest owing to its uniquestructure and chemical properties. Especially, heterocyclic anionexhibited high stability, so that it can be used as ligand and orcoordinated with metal ions to obtain metal complex, which exhibitunique chemical properties and structure.In this thesis, sevel new bidenate ligands(N, N’) and palladiumcomplexes were designed and synthesized on the basis ofdiazaphosphole. Their synthetic method, structure and performancewere studied. The main works are as follows:1. A series of1H-3,5-disubstituted-1,2,4-diazophosphine ofsymmetrical structure were obtained by three-step process at thebeginning of N, N-disubstituted amide. In these compounds,1H-3,5-di-p-methyphenyl-1,2,4-diazophosphine is new compound and itsstructure were analysied through X-ray diffraction.2. Three new2-(3,5-disubstituted-1,2,4-diazaphosphole-1-yl)pyridine were designed and synthesized on the basis of1H-3,5-disubstituted-1,2,4-diazophosphine (R=H, i-Pr, Ph). These newcompounds were characterized by melting point, nuclear magneticresonance (1H NMR,13C NMR,31P NMR), elemental analysis andinfrared spectrum. The palladium complexes were synthesized with the new ligand and Pd(CH3CN)2Cl2.2. Six kinds of2-(3,5-disubstituted-1,2,4-diazophosphine-1-ylmethyl)pyridine (R=H, i-Pr, Ph, p-Me-Ph, t-Bu, thiophyl) weresynthesized and characterized by melting point, nuclear magneticresonance (1H NMR,13C NMR,31P NMR), elemental, the infraredspectrum. The single crystal structure of two compoundssubstituents(R=p-Me-Ph, t-Bu) were obtained and analysied by X-raydiffraction. The corresponding novel metal complexes weresynthesized by reacting Pd(CH3CN)2Cl2with2-(3,5-disubstituted-1,2,4-diazophosphine-1-ylmethyl)(R=i-Pr, Ph,t-Bu). The single crystal structure of palladium(Ⅱ) complex with2-(3,5-diphenyl-1,2,4-diazophosphine-1-ylmethyl)pyridine was obtainedby X-ray single crystal diffraction.