Self–assembly, Structures and Properties of Metal–Organic Frameworks Based on Pyrimidine and Carboxylate Mixed Ligands

• Main Authors: Chih-Min Liou, 劉志明
• Other Authors: Ching-yang Liou
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/03149570960774975563

碩士 === 中國文化大學 === 應用化學研究所 === 95 === Abstract The purpose of this study was to develop a self-assembly strategy for the preparation of novel metal-organic coordination polymers using 2,2’-bipyrimidine (2bpm) as ligand. Treatment of 2bpm with CuCl2, MnCl2 or ZnCl2, using a metal-to-ligand ratio of 4 : 1, afforded blue crystal {Cu(C8H6N4)(C6H4O4S)(H2O)2}.3H2O (1), pale yellow crystal {Mn2(C8H6N4)(C6H4O4S)2(H2O)6} (2), and colorless crystal {Zn2(C8H6N4) (C6H4O4S)2(H2O)6} (3). Each of the three products is a discrete molecule. A solid-state packing diagram showed that molecule 1 formed a Z shape one-dimensional metal-organic Framework via hydrogen-bonding interactions. Compounds 2 and 3 are isostructures. Hydrogen bonding and π–π stacking interactions were key determinants of the final solid state topologies. Compounds {Cd(C8H6N4)(C10H10O6)•H2O}n (4) and {Cd(C10H10O6)(H2O)2}n (5) were obtained form the assembly reaction of 2bpm and CdCl2. For compound 4, coordination of Cd2+ with two bent benzene-1,4-dioxydiacetate (1,4-BDOA) molecules and chelating 2bpm led to the formation of a mill-wheel like 2-D polymer, in which guest water molecules formed strong hydrogen bonding with the host. The Cd2+ ion coordinated only with 1,4-BDOA in compound 5, forming a Z-shaped one-dimensional polymer with ladder topology. The reaction of ZnCl2 with 2bpm in the presence of p-phenylenediacrylic acid (p-PDA) or 4-carboxycinnamic acid (4-CCA) produced 2D polymers {Zn2(C8H6N4) (C12H10O4)2(H2O)2.CH3OH.3H2O}n (6) and {Zn2(C8H6N4)(C10H8O4)2(H2O)2.6H2O}n (7), respectively. Three-dimensional networks were observed in the packing diagram due to hydrogen bonding between ladders. In 6, guest water and methanol molecules are resided in channels due to hydrogen-bonding interactions. In 7, six guest water molecules also were found in channels as a result of hydrogen-bonding with the host.