A Novel Inorganic-organic Hybrid Borate with Unique One-dimensional Infinite Aluminium-oxygen Chains

A novel inorganic-organic hybrid borate,Al2(fum)(H3BO3)(OH)4]n·n(H3BO3)(1,H2fum=fumaric acid),has been synthesized and characterized by single-crystal X-ray diffraction,FTIR and elemental analysis.Crystal data for compound 1:orthorhombic,space group Pnma,a=14.108(3),b=6.9412(14),c=14.995(3)A,V=1468.3(5)A3,Z=4,Mr=359.72,Dc=1.627g/cm3,μ=0.254 mm-1,F(000)=736,the final R=0.0492 and wR=0.1650 with I＞2σ(I).In compound 1,each AlⅢ ion is coordinated by six oxygen atoms to adopt a distorted octahedral geometry.Both fumarate anion and the coordinated boric acid act as bidentate bridging ligands to link two neighboring AlⅢ centers simultaneously.Each AlⅢ ion is bridged by two μ2-hydroxyl ligands to construct an infinite wave-like Al2(fum)(H3BO3)(OH)4]n.chain.These one-dimensional chains form hydrogen bonds with free boric acid molecules giving rise to a three-dimensional supramolecular network.