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The synthesis and structural characterization of two new gallium polynuclear aqua complexes, the supramolecular compound of cucurbit[6]uril with gallium aqua complex containing 32 metal atoms [Ga32(mu4-O)12(mu3-O)8(mu2-O)7(mu-OH)39(H2O)20](PyHsubsetC36H36N24O12)3(NO3)6.53h2O and the tridecanuclear gallium aqua complex [Ga13(mu3-OH)6(mu2-OH)18(H2O)24](NO3)15.12H2O are reported. Two modes of nucleation exist when Ga(sub 3+(aq) is hydrolyzed, one around the tetrahedral GaO4 units and the other around the octahedral GaO6 units.

The hydrothermal conditions from aqueous solutions of lanthanide(III) bromides, CB[6], and 4-cyanopyridine were employed to synthesize the sandwich-type tetranuclear lanthanide complexes with cucurbit[6]uril. The chainlike crystal structure of polymers (Ln = La, Pr, and Dy) are constituted by the sandwich complexes linked via the coordination of IN nitrogen atoms to the silver atoms and could be used as precursors for the synthesis of lanthanide-silver heterometallic coordination polymers.

The syntheses, molecular and crystal structures, and electrochemical properties of three new inclusion compounds derived from cobalt(III) and nickel(II) complexes with 1,3-diaminopropane (tn) or 1,3-diamino-2-propanol (tmOH) and the macrocyclic host cucurbit[8]uril is reported. The results showed that the encapsulation of trans-[[Co[(tn).sub.2][Cl.sub.2]].sup.+] within the cavity of CB[8] stabilizes the complex toward ligand substitution reaction in aqueous solution.

An example of selective isolation of a minor isomer (trans-[[Co(en)2Cl2].sup.+]) is presented from the mixture of isomers (cis and trans) through the formation of an inclusion compound with a macrocyclic host (cucurbit[8]-uri). The encapsulation within the CB[8] cavity significantly alters the properties of guest cation trans-[[Co(en)2Cl2].sup.+] in both solid state and solution.

Mechanochemical reaction of cluster coordination polymers (sub infinity)(super 1)[M3Q7Br4] (M=Mo, W; Q=S, Se) with solid K2C2O4 leads to cluster core excision with the formation of anionic complexes [M3Q7(C2O4)(sub 3)](super 2+). All compounds were characterized by X-ray structure analysis.

Two examples of a new family of supramolecular assemblies based on cucurbituril adduct of hydrogen-bonded molybdenum and tungsten incomplete cuboidal aqua complexes are presented. The novel molecular container assemblies are capable of encapsulation of guest molecules in solution.

Mechanochemical reaction of cluster coordination polymers ¹∞[M3Q7Br4] (M = Mo, W; Q = S, Se) with solid K2C2O4 leads to cluster core excision with the formation of anionic complexes [M3Q7(C2O4)3]2-. Extraction of the reaction mixture with water followed by crystallization gives crystalline K2[M3Q7(C2O4)3]·0.5KBr·nH2O (M = Mo, Q = S, n = 3 (1); M = Mo, Q = Se, n = 4 (2); M = W, Q = S, n = 5 (3)). Cs2[Mo3S7(C2O4]·0.5CsCl·3.5H2O (4) and (Et4N)1.5H0.5K[[Mo3S7(C2O4)3]Br]·2H2O (5) were also prepared. Close Q···Br contacts result in the formation of ionic triples [[M3Q7(C2O4)3]2Br]5-in 1-4 and the 1:1 adduct [[Mo3S7(C2O4)3]Br]3- in 5. Treatment of 1 or 2 with PPh3 leads to chalcogen abstraction with the formation of [Mo3(µ3-Q)(µ2-Q)3(C2,O4)3(H2O)3]2-, isolated as (Ph4P)2[Mo3(µ3-S)(µ2-S)3(C2O4)3(H2O)3]·11H2O (6) and (Ph4P)2[Mo3(µ3-Se)(µ2-Se)3(C2. All compounds were characterized by X-ray structure analysis. IR, Raman, electronic, and 77Se NMR spectra are also reported. Thermal decomposition of 1-3 was studied by thermogravimetry. [ABSTRACT FROM AUTHOR]

From solutions of seleno bridged triangular cluster Mo3Se4(aq)4+ in HCl, crystalline adducts with cucurbituril (Cuc, C36H36N24O12) of different composition, depending on HCl concentration, were isolated. From 2 M HCl, a monosubstituted cationic cluster crystallizes as {[Mo3Se4Cl(H2O)8]2(C36H36N24O12)}Cl6·16H2O (1). Increase in HCl concentration to 6 M gives a pentasubstituted anionic species, (H3O)2[Mo3Se4Cl5(H2O)4]2(C36H36N24O12)·15H2O (2). The crystal structures of 1 and 2 were determined by X-ray crystallography. Each portal of Cuc in 1 is covered with cluster cations [Mo3Se4Cl(H2O)8]3+ like a ‘lid’ on a ‘barrel’. Six water molecules in the trans position to the core μ2-Se form complementary hydrogen bonds with oxygen atoms of Cuc (O⋯O, 2.713–3.067 A˚). In 2 the complementarity is lost and the main structure building factor is short Se⋯Se interactions (Se⋯Se, 2.96–3.43 A˚) between two adjacent anionic clusters. Stereochemistry of halide substitution in the triangular clusters M3Q4 is analyzed. [Copyright &y& Elsevier]