Hydrothermal Syntheses, Crystal Structures And Properties Of Metal Phosphites/phosphates

Microporous materials have attracted considerable research interest owing to their rich structural chemistry and potential applications in catalysis, gas storage, adsorption and separation. The aim of this thesis is to explore the hydrothermal/ solvothermal preparation of metal phosphates/phosphites materials by selecting different types of SDAs as ligands or utilizing the in-situ N-alkylation transformations of templates. The structures of these compounds have been determined by single-crystal X-ray diffraction, and further characterized by elemental analysis, IR, powder X-ray diffraction, thermogravimetric and fluorescence analysis. And our work is mainly focused on:1. By selecting different types of organic amines, such as linear aliphatic amines or aromatic amines as ligands, four new inorganic–organic hybrid open-framework zinc phosphates/phosphites, [C6N2O2H16][Zn(HPO3)]2(3-1),(NH4)[Zn5(PO4)3(HPO4)2(HAPIM)2]·(H2O)(3-2), [Hampy][Zn2(HPO3)(PO4)](3-3), [ampy][Zn2(HPO3)](3-4)have been synthesized under hydrothermal conditions. Compound 3-1 is a 3D inorganic–organic hybrid metal phosphite to be prepared with flexible aliphatic polyamines acting as pillaring ligands. Compounds 3-2~3-4 are all synthesized by using the aromatic amines as ligands. It’s worth noting that the amines play dual roles as both ligands and countercations in compound 3-2 and 3-3. The structure of compound 3-2features unusual three-dimensional microporous framework with extra-large 16-ring channels. Compound 3-3 displays a 2D layered structure and has fluorescence and photochromic properties. The structure of compound 3-4 consists of neutral layers of zinc phosphite which are further pillared through rigid ligands ampy.2. In methanol-aqueous solutions, we have realized a series of cyclic aliphatic and aromatic amines’ in-situ N-alkylation transformations under hydrothermal conditions. These amines, containing 1,4-diazabicyclo[2,2,2]octane, piperazine, 1,4-dimethylpiperazine,2,6-dimethylpiperazine, pyridine,4, 4’-bipyridine,3-(aminomethyl)pyridine, are all in situ transformed into structurally related N,N’-dimethyl-1,4-diazabicyclo[2,2,2]octane,N,N,N’,N’-tetramethyl-piperazinium, N-methyl-2,6-dimethyl-piperazine, N-methyl--pyridine, N,N’-dimethyl-4,4’-bipyridine, N-methyl-3-(aminomethyl)pyridine. Using these newly in situ generated quaternary ammonium ions as templates, we have successfully synthesized 14 novle metal phosphates/phosphites. Four of them areberyllium phosphates with different dimensions(4-1~4-4); Four are gallophosphates(4-5~4-8); Three are new zinc phosphates(4-9~4-11), and three are novle zinc phosphite compounds(4-12~4-14).