| Abstract |
New copper(II) catalytic systems for the mild oxidative C-H functionalization of cycloalkanes and cycloalkenes were developed, which are based on a series of mixed-ligand aminoalcohol-dicarboxylate coordination polymers, namely [Cu-2(mu-dmea)(2)(mu-nda)(H2O)(2)](n) center dot 2nH(2)O(1), [Cu-2(mu-Hmdea)(2)(mu-nda)](n) center dot 2nH(2)O(2), and [Cu-2(mu-Hbdea)(2)(mu-nda)](n) center dot 2nH(2)O (3) that bear slightly different dicopper(II) aminoalcoholate cores, as well as on a structurally distinct dicopper(II) [Cu-2(H(4)etda)(2)(mu-nda)] center dot nda center dot 4H(2)O(4) derivative [abbreviations: H(2)nda, 2,6-naphthalenedicarboxylic acid; Hdmea, N, N -dimethylethanolamine; H(2)mdea, N-methyldiethanolamine; H(2)bdea, N-butyldiethanolamine; H(4)etda, N, N, N , N -tetrakis(2-hydroxyethyl) ethylenediamine]. Compounds 1-4 act as homogeneous catalysts in the three types of model catalytic reactions that proceed in aqueous acetonitrile medium under mild conditions (50-60 degrees C): (i) the oxidation of cyclohexane by hydrogen peroxide to cyclohexyl hydroperoxide, cyclohexanol, and cyclohexanone, (ii) the oxidation of cycloalkenes (cyclohexene, cyclooctene) by hydrogen peroxide to a mixture of different oxidation products, and (iii) the single-pot hydrocarboxylation of cycloalkanes (cyclopentane, cyclohexane, cycloheptane, cyclooctane) by carbon monoxide, water, and a peroxodisulfate oxidant into the corresponding cycloalkanecarboxylic acids. The catalyst and substrate scope as well as some mechanistic features were investigated; the highest catalytic activity of 1-4 was observed in the hydrocarboxylation of cycloalkanes, allowing to achieve up to 50 \% total product yields (based on substrate). |
