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A family of unusual octacopper cage methylsilsesquioxanes 1 - 4 were prepared and characterized. Features of their cagelike (prismatic) structure were established using X-ray diffraction studies. Effects of distortion of prismatic cages 1 - 4 due to variation of (i) additional alkaline metal ions (K, Rb, or Cs), (ii) combination of solvating ligands, and (iii) nature of encapsulating species were found. Opportunities for the design of supramolecular 1D extended structures were found. These opportunities are based on (i) formate linkers between copper centers (in the case of Cu 8 K 2 -based compound 2 ) or (ii) crown ether-like contacts between cesium ions and siloxane cycles (in the case of Cu 8 Cs 2 -based compound 4 ). Cu 8 Cs 2 -complex 4 was evaluated in the catalysis of alkanes and alcohols. Complex 4 exhibits high catalytic activity. The yield of cyclohexane oxidation products is 35%. The presence of nitric acid is necessary as a co-catalyst. The oxidation of alcohols with the participation of complex 4 as a catalyst and tert-butyl hydroperoxide as an oxidizer also proceeds in high yields of up to 98%.

A series of phenylsilsesquioxane-benzoate heptacopper complexes 1 - 3 were synthesized and characterized by X-ray crystallography. Two parallel routes of toluene spontaneous oxidation (into benzyl alcohol and benzoate) assisted the formation of the cagelike structure 1 . A unique multi-ligation of copper ions (from ( i ) silsesquioxane, ( ii ) benzoate, ( iii ) benzyl alcohol, ( iv ) pyridine, ( v ) dimethyl-formamide and ( vi ) water ligands) was found in 1 . Directed self-assembly using benzoic acid as a reactant afforded complexes 2 - 3 with the same main structural features as for 1 , namely heptanuclear core coordinated by ( i ) two distorted pentameric cyclic silsesquioxane and ( ii ) four benzoate ligands, but featuring other solvate surroundings. Complex 3 was evaluated as a catalyst for the oxidation of alkanes to alkyl hydroperoxides and alcohols to ketones with hydrogen peroxide and tert-butyl hydroperoxide, respectively, at 50 °C in acetonitrile. The maximum yield of cyclohexane oxidation products as high as 32% was attained. The oxidation reaction results in a mixture of cyclohexyl hydroperoxide, cyclohexanol, and cyclohexanone. Upon the addition of triphenylphosphine, the cyclohexyl hydroperoxide is completely converted to cyclohexanol. The specific regio- and chemoselectivity in the oxidation of n -heptane and methylcyclohexane, respectively, indicate the involvement of of hydroxyl radicals. Complex 3 exhibits a high activity in the oxidation of alcohols.

The first examples of metallasilsesquioxane complexes, including ligands of the 8-hydroxyquinoline family 1 - 9 , were synthesized, and their structures were established by single crystal X-ray diffraction using synchrotron radiation. Compounds 1 - 9 tend to form a type of sandwich-like cage of Cu 4 M 2 nuclearity (M = Li, Na, K). Each complex includes two cisoid pentameric silsesquioxane ligands and two 8-hydroxyquinoline ligands. The latter coordinates the copper ions and corresponding alkaline metal ions (via the deprotonated oxygen site). A characteristic (size) of the alkaline metal ion and a variation of characteristics of nitrogen ligands (8-hydroxyquinoline vs. 5-chloro-8-hydroxyquinoline vs. 5,7-dibromo-8-hydroxyquinoline vs. 5,7-diiodo-8-hydroxyquinoline) are highly influential for the formation of the supramolecular structure of the complexes 3a , 5 , and 7 - 9 . The Cu 6 Na 2 -based compound 2 exhibits high catalytic activity towards the oxidation of ( i ) hydrocarbons by H 2 O 2 activated with HNO 3 , and ( ii ) alcohols by tert -butyl hydroperoxide. Studies of kinetics and their selectivity has led us to conclude that it is the hydroxyl radicals that play a crucial role in this process.