Anatoly V. Golovin

Catalytic isomerization of N-allylic substrates with chiral Os3 clusters as potentially enantioselective reaction

Abstract It was shown that the [1,2]-double bond migration of N -allylic compounds catalyzed at ambient temperature by the chiral clusters (μ-H)Os 3 (μ-OCNR 1 R 2 )(CO) 10 , 1 , is not accompanied by a cluster-molecule destruction or change of its configuration. Therefore, this catalytic reaction is perspective for its development as an enantioselective process. The key factor in a capability of 1 to produce the activation is the nature of carboxamido ligand. Deuterium label is not transferred from the μ-D or ND positions of the cluster-catalyst (μ-D)Os 3 (μ-OCNDMe)(CO) 10 , 1a , to an alkene substrate, indicating that these hydrogen atoms do not take part in the reaction. The proposed reaction mechanism is the prototropic hydrogen transfer and involves the alkene insertion into the OsO bond.

Stereospecific coordination ofl-hydroxyproline esters with triosmium clusters

AbstractThe reactions of cluster (μ-H)Os3(CO)10(μ-OH) with ethyl and isopropyl esters ofl-oxyproline were studied. In the presence of Me3NO intermediate complex (μ-H)Os3(CO)9(μ-OH)L (L — isopropyl ester ofl-oxyproline) is formed, which slowly converts to the more stable cluster (μ-H)Os3(CO)9

Preparation and reactivity of metal-containing monomers 53. Synthesis and stability of a cluster monomer (μ-H)Os3(μ-OCNMe2)(CO)9PPh2CH2CH=CH2 in solution

\left\{ {\mu ,\eta ^2 } \right.--{\rm O}|\overline {CHCH_2 CH(COOPr^i )NH} \mathop C\limits^| \left. {H_2 } \right\}

Preparation, X-ray structure, copolymerization with styrene of [(μ-H)Os3(μ-OCNMe2)(CO)9{P(CH2CHCH2)Ph2}] and catalytic properties of the cluster/styrene copolymer

. Cluster complexes containing chelate-bridging heterocycles were also obtained by heating (μ-H)Os3(CO)10(μ-OH) with esters ofl-oxyproline. In both cases, only one of the possible diastereomeric complexes (μ-H)Os3(CO)9

Synthesis and comparative study of the physicochemical properties of the related optically active complexes [(μ-H)Os3{μ-OCNH-(R)-CHMePh}(CO)9L]{L=CO, NMe3, (S)-(−)-, or (R)-(+)-NH2CHMePh}, toward the cluster and amino ligand configuration determination

\left\{ {\mu ,\eta ^2 } \right.--{\rm O}|\overline {CHCH_2 CH(COOPr^i )NH} \mathop C\limits^| \left. {H_2 } \right\}

Study of allylic rearrangement in (-H)Os 3 (-O=CNRCH 2 CH=CH 2 )(CO)<su

(R = Et, Pri) is formed, which indicates that the reactions are stereospecific. Based on analysis of Dreidings models, an attempt to determine the absolute configuration of the obtained clusters was made.