V. A. Sergeev

Interaction of chromium vapour with benzonitrile and bromobenzene

Abstract Bis(benzonitrile)chromium was isolated from the reaction of benzonitrile with chromium vapour. The major process was accompanied by cyclotrimerization of benzonitrile to form 2,4,6-triphenyltriazine. Phenyl bromide reacted with chromium to give insignificant amounts of cationic bis(arene)chromium compounds containing bromobenzene, diphenyl and benzene as ligands.

Membrane catalysts for hydrogenation with cryochemically synthesized palladium clusters

New type of membrane catalysts has been prepared through blinding of 2–3 µm pores of cermet membranes with Pd clusters from its cryochemically synthesized sol in toluene. Those catalysts display 30 times superior activity with respect to Pd weight than the membrane catalysts in the form of foil from Pd alloys.

Metal complexes in catalytic conversions of olefins. 4. Heterogenization of nickel complexes on chemically modified silochrome surface; activity and selectivity in ethylene dimerization

When activated by Et2AlCl phosphine-containing homogeneous nickel complexes and their heterogenized analogs (HMC) formed on silochrome S-120 modified by NH2 and N(PPh2)2 groups differ significantly in their effectiveness in ethylene dimerization. The catalytic activity of Ni-HMC-Et2AlCl depends on how the HMC was formed. Ni-HMC-I obtained by ligand exchange on chemically modified silochrome is ∼5–15 times more effective than Ni-HMC-II synthesized from the gas phase. The selectivity in formation of α-olefins (σC4 + σC6) is ∼4–5 times higher in the presence of Ni-HMC than for its homogeneous analogs.

Ferromagnetic resonance of products of low-temperature cocondensation of iron vapors with nonadecane

Conclusions1.We synthesized the products of high-vacuum low-temperature cocondensation of iron vapors with nonadecane, which we investigated by the ferromagnetic resonance method.2.An increase in the iron content in the synthesis products leads to a decrease in the ferromagnetic resonance linewidth and to an insignificant decrease in the g factor.

Synthesis and19F-NMR spectra of fluoro-substituted dibenzenechromium derivatives

Conclusions1.Simultaneous condensation of chromium vapors with the vapors of two substituted benzenes, one of which was fluorobenzene, gives substituted dibenzenechromium complexes of the type (C6H5F)Cr(C6H5X).2.The values of the19F chemical shifts correlate satisfactorily with the σm+ and σmp substituent constants.

Synthesis of fluorine-containing dibenzenechromium nitriles using chromium vapor

ConclusionsThe cocondensation of chromium and two aromatic compounds gives mixed bisarenchromium complexes, namely, fluorobenzene(benzonitrile)chromium and trifluoromethylbenzene(benzo-nitrile)chromium.

Preparation of bisarenechromium π complexes from phenylacetylene and chromium vapors

ConclusionA mixture of isomeric 1,2,4- and 1,3,5-triphenylbenzenes and their π complexes with chromium and also organic and organochromium polymers were formed in the reaction of phenylacetylene with chromium vapors under high vacuum.

Catalytic activity of the products of low-temperature cocondensation of olefins with the vapors of transition metals

Conclusions1.The reaction of 1-hexene with vapors of Cr, Mn, Fe, Co, and Ni in the conditions of the method of high-vacuum, low-temperature cocondensation results in the formation of a suspension which is stable in an atmosphere of argon.2.When the cocondensate is thawed, the starting 1-hexene undergoes catalytic transformations with the formation of products of positional and cis-, trans-isomerization, oligomerization, and dehydrocyclization.

Synthesis of substituted nitriles of dibenzenechromium series using chromium vapors

ConclusionsSome mixed bisarenechromium complexes, namely toluene (benzonitrile) chromium, anisole (benzonitrile) chromium, and acetophenone (benzonitrile) chromium were obtained by the reaction of Cr with two aromatic compounds in the vapor phase.