Redox Properties of Heterometallic Osmium Cluster Compounds

Электрохимическими методами изучены редокс-свойства гетерометаллических четырехъядерных анионных [Os3Fe(μ-H)(CO)13]–, [Os3Co(CO)13]– и нейтральных Cp*MOs3(CO)10(μ-H) (μ-Cl) (M = Rh, Ir) кластеров в ацетонитриле и дихлорметане на платиновом, стеклоуглеродном и ртутном капельном электродах. Показано, что в результате редокс-превращений всех изученных гетерометаллических кластеров происходит элиминирование M-содержащих (М = Fe, Co, Rh, Ir) фрагментов и образование гомометаллических трехъядерных кластеров осмия, участвующих в дальнейших электрохимических реакцияхThe redox properties of heterometallic anionic [Os3Fe(μ-H)(CO)13]–, [Os3Co(CO)13]– and neutral Cp*MOs3(CO)10(μ-H)(μ-Cl) (M = Rh, Ir) clusters were studied by electrochemical methods at platinum, glassed carbon and dropping mercury electrodes in acetonitrile and dichloromethane solutions. It was established that redox transformations of these heterometallic clusters results in the elimination of M-containing (М = Fe, Co, Rh, Ir) fragments and the formation of homometallic trinuclear osmium clusters, which undergoes further electrochemical reaction

Unusual Synthesis of Triosmium Carbene Clusters by Tandem Activation of Chlorohydrocarbons and Heterocyclic Amines

Reactions of the [Os3H2(CO)(10)] cluster complex (1) with six-membered heterocyclic amines (morpholine, thiomorpholine, piperidine) and halohydrocarbons (CH2Cl2, ClHC=CHCl, CH2=CCl2) at similar to 25 degrees C have been studied. Two main types of products are formed in all studied reactions. One product is carbene cluster [Os-3(mu-H)(mu-Cl){eta(1)-C(CH3)N(CH2CH2)(2)X}(CO)(9)] (X=O, S, CH2) (3, 3 a and 3 b). Second product is cluster containing enamine ligand [Os-3(mu-H){mu-CH=CHN(C2CH2)(2)X)}(2)(CO)(10)] (X=O, S, CH2) (2, 2 a and 2 b). The carbene ligand is assembled on a cluster, from three organic molecules, thus representing the first example of carbene ligands formed in this way. Clusters with carbene ligand exist as two stable isomers (rotamers hindered towards the Os-C bond), as confirmed by NMR studies and conformational analysis. We have found that in reactions of cluster 1 with acyclic amines containing an oxygen atom in gamma-position (likely morpholine in CH2Cl2), only complexes with bridging enamine ligands are formed. Compounds 2 a, 2 b, 3 and 3 b are characterized by single-crystal X-ray diffraction

Redox Properties of Heterometallic Osmium Cluster Compounds

Электрохимическими методами изучены редокс-свойства гетерометаллических четырехъядерных анионных [Os3Fe(μ-H)(CO)13]–, [Os3Co(CO)13]– и нейтральных Cp*MOs3(CO)10(μ-H) (μ-Cl) (M = Rh, Ir) кластеров в ацетонитриле и дихлорметане на платиновом, стеклоуглеродном и ртутном капельном электродах. Показано, что в результате редокс-превращений всех изученных гетерометаллических кластеров происходит элиминирование M-содержащих (М = Fe, Co, Rh, Ir) фрагментов и образование гомометаллических трехъядерных кластеров осмия, участвующих в дальнейших электрохимических реакцияхThe redox properties of heterometallic anionic [Os3Fe(μ-H)(CO)13]–, [Os3Co(CO)13]– and neutral Cp*MOs3(CO)10(μ-H)(μ-Cl) (M = Rh, Ir) clusters were studied by electrochemical methods at platinum, glassed carbon and dropping mercury electrodes in acetonitrile and dichloromethane solutions. It was established that redox transformations of these heterometallic clusters results in the elimination of M-containing (М = Fe, Co, Rh, Ir) fragments and the formation of homometallic trinuclear osmium clusters, which undergoes further electrochemical reaction