Hydrothermal Synthesis And Structural Characterization Of Organic - Inorganic Hybrid Compounds. Vanadium Cluster

In this paper, six novel organic/inorganic hybrid complexes: [Zn(phen)(H20)V206] 1, [NH4]2[Zn(phen)3]2[Zn(phen)2(H2O)2][V16O38 (C1)]-5H20 2, H3[Cu(phen)2]s[V16038(Cl)]-3H20 3, H3[Cd(phen)2(H2O) (Cl)][{Cd(phen)2(H20)}2{V16038(Cl)}]-3.5H20 4, H3[Cd(phen)3][{Cd(phen)2 (H20)}2{V16038(C1)}]-3.5H20 5 and [Fe(phen)2]2[As8[V14O42(H2O)o.5]-H2O 6. have been hydrothermally synthesized through modifying synthetic conditions and starting materials. Structures of the six complexes have been determined by single crystal X-ray diffraction, and the influencing factors on structures of hybrid complexes have been discussed. Complex 1 exhibits ribbon-like structure covalently constructed from cyclic tetramer [V4Oi2]4" subunits and [Zn(phen)(H2O)]2+ fragments, this connectivity mode generates hexametallic, 12-membered [(Zn-phen)2V4Oi2] rings with the [VO4J tetrahedron corner-connected along ar-axis, the phen groups decorating the ribbon on theperiphery. The Compound 2 consists of one [Vi6O3g(Cr)] " anion and two kinds of cations: [Zn(phen)3]2+ and [Zn(phen)2(H2O)2]2+, while the compoud 3 consists of one [Vi6O38(Cr)]8" anion and five [Cu(phen)2]+ cations. In these two hybrid complexes, the "naked" [Vi6O3s(Cr)]8~ is the first observation in polyoxovanadate chemistry up to now. Compound 4 consists of chiral [{L/D-Cd(H2O)(phen)2}2{V16O38(Cl)}]4- polyoxoanions and L/D-[Cd(Cl)(H2O) (phen)2]+ cation. In the 3-D structure of 4, a novel supramolecular assembly of enantiomers L/D-[Cd(Cl)(H2O)(phen)2]+ is formed via strong intermolecular H-bonding and n-n stacking interactions with chiral chains of [{L/D-Cd(H2O)(phen)2}2 {Vi6O38(Cl)}]4', racemic layers and channels. The channels contain enantiomers L/D-[Cd(Cl)(H2O)(phen)2]+ in pairs. In order to study the influence of chiral cations on the structure of compound, we synthesized compound 5 with different chiral cation [Cd(phen)3]3+ and different polyoxoanions [{Cd(H2O)(phen)2}2{V16O38(Cl)}]4'. To our knowledge, in these two hybrid complexes, such discrete hexadecavanadate cluster coordinated to transition-metal complexes with chiral structure isreported for the first time. Compound 6 consists of arsenic-vanadium polyoxoanions [AsgfVuC^tbCOo.s]4* and transition-metal complexes[Fe(phen)2]2+ cations. [Fe(phen)2] complex fragments form one dimensional supramolecular chain through TI-'-TI stacking interactions, and pack into three dimensional framework with [As8[Vi4O42(H2O)o.s]4+ cluster by strong intermolecular H-bonding. Other characterizations for these six complexes by elemental analysis, IR, ESR, XPS, and thermal analysis have also been described.