A novel flower-like hydrated magnesium carbonate hydroxide,Mg_5(CO_3)_4(OH)_2·4H_2O,with micro-structure composed of individual thin nano-sheets was synthesized using a facile solution route without the use of template or organic surfactant.Reaction time has an important effect on the final morphology of the product.The micro-structure and morphology of Mg_5(CO_3)_4(OH)_2·4H_2O were characterized by means of X-ray diffractometry(XRD),field-emission scanning electron microscopy(FE-SEM).Brunauer-Emmett-Teller(BET)surface areas of the samples were also measured.The probable formation mechanism of flower-like micro-structure was discussed.It was found that Mg_5(CO_3)_4(OH)_2·4H_2O with flower-like micro-structure was a novel and efficient catalyst for the synthesis of diphenyl carbonate(DPC)by transesterification of dimethyl carbonate(DMC)with phenol.
WANG QiangWANG Ke-liWU Xing-longLUO Sheng-junHU Chang-wen
A new three-dimensional supramolecule composed of copper-Schiff base complex, [Cu(naphdien)]Cl·H2O, where naphdien is Schiff base of 2-hydroxy-1-naphthaldehyde and diethyle- netriamine, has been synthesized and determined by single-crystal X-ray diffraction. It belongs to the monoclinic system, space group P21/c, with a = 7.3490(15), b = 7.0847(16), c = 30.845(3), β = 95.33(3)°, V = 1599.0(5)3, Z = 4, C15 H20ClCuN3O2, Mr = 373.33, Dc = 1.551 g/cm3, μ = 1.543 mm-1, F(000) = 772, R = 0.0536 and wR = 0.0927 for 2788 unique reflections with 1659 observed ones (I >2σ(I)). In the crystal structure, mononuclear units [Cu(naphdien)]Cl·H2O are linked into a two-dimensional framework via strong hydrogen bonds, and extended into a three-dimensional supramolecular structure through π-π stacking interactions.
