Features of the decomposition of H2O2 in the presence of polynuclear complexes with Co2Cu2 and Co3Cu2 metal cores with deprotonated and di- and triethanolamines (H2Dea and H3Tea), compounds with the composition (H2Tea)ConCumCl (m + n =1; n = 0.33, 0.5, 0.67), and mononuclear complexes (H2Tea)CuCl and (H2Tea)CoCl were examined. It is suggested that the reaction in the presence of poly- and mononuclear complexes has different mechanisms.

Основным продуктом окисления кислородом воздуха при комнатной температуре смеси комплекса состава (СоII)3( -OOCBut)6(NEt3)2 и дибензилового эфира (DBE) в растворе дихлорметан–бензол (4 : 1) является гексаядерный комплекс [(CoIII)6( 4-O)2( 3-O)2( -OOCBut)9(OH)2(HOOCBut)](HNEt3) · 0.5DBE · C6H6 (I). Mеталлоостов I, по данным РСА, содержит псевдокубановый фрагмент [Co4( 4-O)2( 3-O)2], связанный с двумя “периферийными” ионами кобальта(III). Обсуждаются возможность функционирования полученного комплекса в качестве интермедиата-катализатора жидкофазного окисления DBE и особенности конформационных изменений в молекуле DBE, обусловленные характером адаптации последней соответствующим металлокомплексом.

Room-temperature oxidation of a mixture of the complex (CoII)3(μ-OOCBu t )6(NEt3)2 and dibenzyl ether (DBE) with atmospheric oxygen in dichloromethane-benzene (4: 1) gave the hexanuclear complex [(CoIII)6(μ4-O)2(μ3-O)2(μ-OOCBu t )9(OH)2(HOOCBu t )](HNEt3) · 0.5DBE · C6H6 (I) as the major reaction product. According to X-ray diffraction data, the metal framework of complex I contains the pseudocubane fragment [Co4(μ4-O)2(μ3-O)2] linked with two “peripheral” cobalt(III) ions. The possibility of using complex I as an intermediate catalyst for liquid-phase oxidation of DBE as well as the conformational changes in the DBE molecule due to its adaptation to the metal complexes are discussed.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

On the base of the kinetic and activation parameters of the hydrogen peroxide decomposition in the presence of chelates of CoX2 salts (X = Cl, Br, I, NCS) with N,N,N′,N′-tetrasubstituted thiocarbamoylsulfenamides containing exocyclic (out-of-chelate) fragments of dimethylamine (I), piperidine (II), and piperazine (III) the nature of acido-ligands influence on catalase activity of complexes I–III was revealed, depending on the structure and composition of the chelating ligand. Mononuclear complexes I(Br) and II(Br) can transform into 10-membered binuclear macrochelate intermediates.

Reactions of copper(II) carboxylates with dibenzyl ether (DBE) gave binuclear complexes of the formula Cu2(μ-OOCR)4(DBE)2 (R = Bu t , Ph, and CF3). The complexes were characterized by X-ray diffraction. The axial positions in the lantern-type dimer are occupied by the coordinated DBE molecules. The complexes seem to be analogs of intermediate catalysts for the oxidation of DBE with atmospheric oxygen in the presence of transition metal complexes. When stored in air, the complex Cu2(μ-OOCPh)4(DBE)2 underwent oxidation into Cu2(μ-OOCPh)4(HOOCPh)2, which was characterized by X-ray diffraction. The geometry of its framework is similar; the structure is stabilized by intramolecular H bonds between the axially oriented benzoic acid molecules and the adjacent bridging benzoate anions.

We have obtained complexes of Co(II) with 1,4-piperazine-bis(carbothiosulfene diethylamide) (L) of composition [Co2LX4] (X = Cl, Br, I, NCS). We discuss the characteristic features of the decomposition kinetics for H2O2 in the presence of these complexes and the effect of the acido ligands X on their catalytic activity. We have observed isokinetic relationships between the activation parameters and the reaction rate constants. We show that the values of the parameters α and β in the Edwards equation to a considerable extent are due to the composition of the complexes and the ratio [H2O2]0/[Cat]0.

The main products from the liquid-phase oxidation of cyclohexane (CH) by air (333 K) in the presence of the pivalate complexes of cobalt with nuclearity n = 1–4 are the respective hydroperoxide (HP) and cyclohexenone. The effect of n on the rate of formation W HP (Co1<Co4 <Co3 <Co2) differs a little for the W HP/n values (Co4<Co1<Co3<Co2) and particularly for W CH/n (Co4<Co1<Co2<Co3). The factors giving rise to the differences in the catalytic characteristics of the complexes are discussed.

The main products of the reaction in the presence of homo- and heteroligand pivalate and 3,5-dimethylpyrazolate mono-, bi-, and trinuclear complexes of Co, Cu, Ni, and Zn are the hydroperoxide, benzaldehyde, and benzoic acid. The effect of the composition and structure of the complexes on the conversion of the substrate, the selectivity of the process, and the possibility of alternative routes to the oxidation of dibenzyl ether is discussed.

It was found that during the liquid-phase oxidation of cyclohexene (CH) by air (323–343 K) in the presence of a series of homo-and heteronuclear µ 3-oxotrimetallohexapivalates with a M2M′O (M, M′ = Co, Cr, Fe, Ni) core insignificant amounts of the corresponding epoxide are formed, and 3-hydroperoxy-2-cyclohexene (HP), 3-hydroxy-2-cyclohexene (CHol), and 2-cyclohexen-3-one (CHone) accumulate in the oxidate. It is suggested that CHone and CHol are “dead-end” products from the oxidation of CH under the investigated conditions while the HP is a unique “intermediate-damper” that gives rise to the realization of alternative paths (catalytic cycles) for the formation of these products.

Results are given for a kinetic study of the decomposition of the hydroperoxide (HP) of dibenzyl ether (DBE) to give oxidates of the latter in the presence of complexes Cr2MOPiv6·3L(M = Cr(III), Fe(III), Ni(II), and Co(II); L = PPy, γ-Pic, and H2O). The experimental data were satisfactorily described assuming that the formation of an HP–catalyst intermediate complexes is the rate-limiting step and the catalyst is deactivated by components of the DBE oxidate and taking account of the noncatalytic decomposition of the HP.

On the basis of a comparison of the rates of formation of the hydroperoxide, benzaldehyde, and benzoic acid—the basic products of the liquid-phase oxidation of dibenzyl ether in the presence of complexes with the composition Cr2MOPiv6·3L (M=Cr(III), Fe(III), Ni(II), Co(II); L=PPy, γ-Pic, H2O)—it was concluded that, when the sequence of reactions dibenzyl ether→hydroperoxide→benzaldehyde has occurred to a small extent, activation of the substrates occurs at the same catalytic center.