Design of ecologically safe and science intensive electrochemical processes

This review discusses the results of and prospects for studies aimed at design of new science intensive, environmentally safe technologies for the synthesis of organophosphorus compounds by halogenation of α-olefins, including modification of rapeseed oil; it also considers methods for the production of some other intermediates for chemical industry. New synthetic applications have been developed, using combined methods of classical organic chemistry and electrochemistry, for processes based on electrochemical generation of catalysts (mediators)—complexes of metals in low oxidation states, halogen complexes, etc. Selective electrochemical procedures are suggested for the synthesis of triphenylphosphine, trialkylphosphates, and nanosized transition metal phosphides from white phosphorus.     

Aromatization of methylcyclopentane and cyclohexane over zinc-containing high silica zeolites

High catalytic activity and selectivity of high silica zeolites containing no cations of noble metals, towards aromatization of methylcyclopentane (MCPA) and cyclohexane (CHA) has been revealed.

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New nanoheterostructures based on astralenes: Spectral characteristics and some application aspects

Original compositions in the form of suspensions of astralenes with luminescing solubilizers in various solvents, including liquid crystals (LCs), are developed. Using an LC composition as an example, the possibility of extending the dynamic range of optical limiting due to the joint action of two-photon absorption in the LC matrix and stimulated scattering by carbon nanoparticles is demonstrated. The spectral and luminescent characteristics of such suspensions are determined. The role played by the photochemical factor in the photodynamics of optical limiting in carbon heteronanostructures is discussed.     

Germylene complexes of tungsten pentacarbonyls W(CO)5GeCl2 and W(CO)5GeW(CO)5: Electrochemical synthesis and quantum-chemical computations

Convenient synthetic route to prepare the germylene complexes of tungsten pentacarbonyls, W(CO)₅GeCl₂ and W(CO)₅GeW(CO)₅, electrochemically is developed. Combined quantum-chemical/IR spectroscopic approach is used for identification of the synthesized compounds. Good agreement between theoretical and experimental spectra can be regarded as one of the proofs of their supposed structures.     

Electrochemical nickel-induced fluoroalkylation: synthetic, structural and mechanistic study

Electrocatalytic generation of nickel catalysts in low oxidation states by reduction of nickel complexes with various ligands (2,2'-bipyridine, 2,2':6',2'-terpyridine, (S,S)-2,6-bis(4-phenyl-2-oxazolin-2-yl)-pyridine) in the presence of olefinic substrates and fluoroalkyl halides leads to new organic products derived from addition-dimerization processes. Due to the presence of two stereocenters in the dimerization products two diastereomers were characterized by a variety of analytical techniques including multi-dimensional NMR methods and X-ray single crystal diffraction. The formation of dimers was prevented by the inclusion of the hydrogen atom donor tributyltin hydride. The cyclic voltammetry study of selected nickel complexes along with fluoroalkyl halides demonstrated that Ni(I)L is the active form of the catalyst.     

Features of the Formation of Composite Materials in Anisotropic Liquid Systems with Elongated Suspended Particles

The equations of rotational motion of nondeformable spherical and axisymmetric elongated particles and a rheologic equation for stresses in arbitrary gradient flows of dilute suspensions of such particles in an anisotropic carrying fluid are obtained within the framework of a structural-phenomenological approach. As a rheologic model of the suspension-carrying fluid and a hydrodynamic model of the suspended particles, we use the Ericksen simple anisotropic fluid and a symmetric triaxial dumbbell, respectively. The constitutive equations obtained are used to study the effect of anisotropy of the carrying fluid on the dynamics of suspended particles and on the rheologic properties of suspensions in a simple shear flow. A stationary orientation of the elongated suspended particles under the action of hydrodynamic forces is discovered. The possibility of applying this phenomenon to the formation of composite materials is discussed.