Research in the field of highly energetic materials is nowadays directed towards the syntheses of simple molec...
Qi Yang,Gang Xie,Sanping Chen,Shengli Gao Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, Shaanxi Key Laboratory of Physico-Inorganic Chemistry,College of Chemistry and Materials Science, Northwest University,Xi’an,710069,China
Three new cobalt（II） coordination compounds, [Co（3,3＇-Hbpt）2（H2pm）（H20）2]＇2H20 （1）, [Co（4,4＇-Hbpt）（pm）0.5（H20）]＇3H20 （2） and [Co（3,4＇-Hbpt）（pm）0.5（H20）3]＇2H20 （3） （3,3＇-Hbpt = 3,5-bis（3-pyridyl）-lH-1,2,4-triazole; 4,4＇-bpt = 3,5-bis（4-pyridyl）- 1H-1,2,4-triazole, 3,4＇-Hbpt = 3-（3-pyridyl）-5-（4＇-pyridyl）-lH-1,2,4-triazole and Hapm = pyromellitic acid） have been synthe- sized by hydrothermal reactions. Single-crystal X-ray diffraction reveals that compound 1 has a one-dimensional （1D） chain network, 2 exhibits a four-connected three-dimensional （3D） structure with 1D open channels encapsulated by water molecules, while 3 displays a regular two-dimensional （2D） architecture connected through 1D metal helical chains. In addition, the effi- cacy of compounds 1-3 as additives to promote the thermal decomposition of ammonium perchlorate （AP） is explored by dif- ferential scanning calorimetry （DSC）.
A 3D mixed-valence Co（Ⅲ）-Co（Ⅱ） compound [Co9（bta）10（Hbta）2（H2O）10]n·[22（H2O）]n （1） （H2bta=N,N-bis（1H-tetrazole-5- yl）-amine） was hydrothermally synthesized by reaction of Co（NO3）2·6H2O with H2bta·H2O. Compound 1 consists of three kinds of distorted-octahedral [CoⅡ（N4O2）] paramagnetic nodes which are separated by [CoⅢ（bta）2（Hbta）]2-/[CoⅢ（bta）3]3- dia- magnetic linkers to generate a 3D porous metal-organic framework （MOF） with alternative …Co（Ⅲ）…Co（II）… array and channels incorporating water molecules. Under an applied magnetic field of 4000 Oe, compound 1 exhibits slow relaxation of magnetization at low temperatures, giving AE/kB=30.O0 K and ι0=2.0×10^-8 s.
Five transition metal coordination compounds, [Mn2（8-qoac）E（bdc）（H2O）4]（1）（8-qoacH=quinoline-8-oxy- acetate acid, H2bdc=benzene-1,4-dicarboxylic acid）, [Zn4（8-qoac）4（bdc）2]n（2）, {[CdE（8-qoac）E（Hip）2（H2O）2]·（H2O）4}n（3）（H2ip=benzene-1,3-dicarboxylic acid）, [Pb3（8-qoac）2（bdc）1.5（HEO）Cl]n（4） and [Zn2（8-qoac）（8-ql）（bdc）]n （5）（8-Hql=8-hydroxyquinoline）, were synthesized by hydrothermal syntheses of metal salts with benzenedicarboxy- lic acid and 8-qoacH. Compound 1 possesses a discrete dimer bridged by bdc2- ligand. Compound 2 presents a 2D layer network constructed from bdc2- linkers and 1D infinite ribbons, in which Zn（II） centers are bridged by 8-qoac- with a tetradentate binding mode. Compound 3 displays a 1D zigzag chain, with adjacent chains further connected via extensive O-H…O hydrogen bonds to generate a 3D supramolecular structure. Compound 4 shows a 3D framework containing trinuclear lead secondary building units and bdc2- linkers, in which a new coordination mode of 8-qoac- ligand is observed. In compound 5, Zn（II） ions are simultaneously bridged by 8-qoac-, 8-ql- and bdc2- ligands to form tetranuclear zinc units, which are further interlinked by bdc2- linkers to yield a 2D wave-like layer. Based on intrali- gand（IL）（π-π＊） fluorescent emission, compounds 1--5 possess strong purple fluorescent emissions. In addition, the thermal stabilities of compounds 1--5 were studied.
