A series of crystalline nonmetal borate compounds was prepared by reactions of linear α,ω-diaminoalkanes, H2N(CH2) n NH2 (n = 5−12), with excess boric acid in aqueous solution. These simple reagents self-assemble in water to form complex ordered structures. The products were characterized by a combination of elemental, thermal, and X-ray diffraction analyses as well as single-crystal X-ray diffraction studies. In each case except for n = 7 and 12, a bis(pentaborate) product of general formula [H3N(CH2) n NH3][B5O6(OH)4]2 (1, 2, 4−7) was obtained in good yield. When n = 12, the product, [H3N(CH2)12NH3][B5O6(OH)4]2·4H2O (8), contained interstitial water. When n = 7, a product of composition [H3N(CH2) 7 NH3][B8O10(OH)6]·2B(OH)3 (3) was obtained, containing an unusual octaborate anion and interstitial boric acid. The borate anions form hydrogen-bonded supramolecular anionic frameworks that host alkyldiammonium dications. These cations contribute to hydrogen bonding and arrange either extended linearly or folded to varying degrees across channels. This study reveals an interplay between the anionic borate host and the cationic guest in which the nature of the cation controls the borate framework structure, which in turn influences cation conformation.

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New framework materials composed of well-defined vanadium oxide clusters were prepared by low-temperature reactions and characterized by X-ray crystal structure analysis. The structures of these solids contain {V O } cages linked into two interpenetrating three-dimensional networks by bridging {M(H O) } groups (M=Fe , Co ; see picture).

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The hydrothermal reactions of vanadium oxide precursors with trialkoxy ligands of the class (HOCH2)3CR (R = CH3, CH2CH3) yield polyalkoxyoxovanadium clusters with a hexametalate core, Ba[V607(0H)3{(0CH2)3-CCH3}3]-3H20 (1), Na2[V607{(0CH2)3CCH2CH3}4] (2), (Me3NH)[V607(0H)3{(0CH2)3CCH3}3] (3), and Na-[V606F(0H)3{(0CH2)3CCH3}3]'3H20 (4). Cluster 1 is a fully-reduced V(I V) species in which nine doubly bridging oxo groups of the parent {V60i9} core have been substituted by alkoxy oxygen donors of the three trialkoxy ligands. The structure of 3 is grossly similar to that of 1, with differences in metrical parameters reflecting the presence of one oxidized V(V) site in the metal core of 3. The fully reduced cluster 2 exhibits complete substitution of the doubly-bridging oxo groups of the parent core by 12 ligand alkoxy donors. The tendency of polyvanadium oxide clusters to encapsulate a variety of guest molecules or ions is demonstrated by the structure of 4, in which the central Ht-oxo group of the parent core has been substituted by a u3-fiuoride, resulting in a considerably distorted {V6C>6-(m3-F)(m2-OH)3(m2-OR)9J core. Crystal data for 1: hexagonal space group P6}mc, a = 13.707(1) A, c = 9.647(2) A, V = 1569.7(2) A* 123, Z = 2, D^ic -2.140 g cm-3; structure solution and refinement based on 399 reflections converged at R = 0.0576. Crystal data for 2: cubic space group Fd3, a = 19.202

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The synthesis and characterization of the novel systems [Zn(2)(H(2)N(CH(2))(2)NH(2))(5)][(Zn(H(2)N(CH(2))(2)NH(2))(2))(2)V(18)O(42)(H(2)O)].9H(2)O (1), [Cd(2)(H(2)N(CH(2))(2)NH(2))(5)][(Cd(H(2)N(CH(2))(2)NH(2))(2))(2)V(18)O(42)(Br)].9H(2)O (2), and [Zn(2)(H(2)N(CH(2))(2)NH(2))(5)][(Zn(H(2)N(CH(2))(2)NH(2))(2))(2)V(18)O(42)(Cl)].9H(2)O (3) have been described. These materials represent a new class of solids that have been prepared by combining conventional coordination compounds with spherical polyoxovanadate clusters. The isomorphous structures of these hybrid solids consist of two-dimensional arrays of container cluster molecules [V(18)O(42)(X)] (X = H(2)O, Br-, Cl-) interlinked by the transition metal complex moieties [M(H(2)N(CH(2))(2)NH(2))(2)] (M = Zn, Cd). These compounds contain an unprecedented complex cation, [M(2)(H(2)N(CH(2))(2)NH(2))(5)](4+). Crystal data for 1: C(9)H(46)N(9)O(26)V(9)Zn(2), monoclinic space group P2(1)/m (No. 11), a = 12.3723(7) A, b = 20.9837(11) A, c = 15.8379(8) A, beta = 97.3320(10) degrees, Z = 4.