G. I. Nikishin

Bio: G. I. Nikishin is an academic researcher from Russian Academy of Sciences. The author has contributed to research in topics: Radical & Homolysis. The author has an hindex of 11, co-authored 280 publications receiving 540 citations.

Homolytic alkylation of cycloalkanones by 1-alkenes initiated by tertiary-butyl hydroperoxide

Abstract: 1. The possibility of using tert-butyl hydroperoxide to initiate the reaction of homolytic alkylation of cycloalkanones with 1-alkenes at temperatures of 100–140° was studied. 2. Tert-butyl hydroperoxide is analogous to ditert-butyl peroxide in the indicated ability.

Homolytic addition of aliphatic alcohols to tetrachloroethylene in the liquid phase

Abstract: As the result of a radical reaction between tetrachloroethylene and aliphatic alcohols in liquid phase, not only products of the substitution of hydrogen at theα-C atom of the alcohol for the trichlorovinyl group, but also isomers with a trichlorovinyl group at other C atoms, preferably in theω-1 position, are formed.

Oxidative cleavage of 1-alkylcyclopentanols by lead tetraacetate-metal chloride system

Abstract: Oxoalkyl radicals are generated when the lead tetraacetate-alkali or alkaline earth metal chloride system is reacted with 1-alkylcyclopentanols, which are oxidized to chloroketones.

Oxidation of acetoxyalkyl radicals by divalent copper salts

Abstract: 1. The 1-ethyl-3-aeetoxypropyl and 1-ethyl-4-acetoxybutyl radicals were respectively generated by the oxidative decarboxylation of the 2-ethyl-3-acetoxybutanoic and 2-ethyl-4-acetoxypentanoic acids under the influence of lead tetraacetate, and a study was made of their oxidation by the acetate, trifluoroacetate, fluoborate, sulfate, chloride and perchlorate of divalent copper. 2. Most of the copper salts oxidize the 1-ethyl-3-acetoxypropyl and 1-ethyl-4-acetoxybutyl radicals exclusively to the 2- and 3-pentenyl and the 3- and 4-hexenyl acetates, with the predominant formation of the isomers where the acetoxy group is furthest away from the double bond. Ligands that are coordinated with the copper are practically without effect on the ratio of the formed isomeric alkenyl acetates.

Thermal decomposition of cyclic peroxydiacids

Abstract: 1. New cyclic peroxydiacids were synthesized: peroxydi-cis-hexahydrophthalic, peroxydi-cis-Δ4-tetrahydrophthalic, and peroxydi-cis-endomethylene-Δ4-tetrahydrophthalic. 2. The thermal decomposition of peroxydiacids in acetic acid obeys a first-order equation with respect to the peroxide. As a result of the decomposition of the peroxydiacids, anhydrides are formed. A mechanism was proposed for their formation by cyclization of acyloxy radicals.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Cobalt-Catalyzed C―H Activation

Abstract: Catalytic C–H activation has emerged as a powerful tool for sustainable syntheses. In the recent years, notable success was achieved with the development of cobalt-catalyzed C–H functionalizations with either in situ generated or single-component cobalt-complexes under mild reaction conditions. Herein, recent progress in the field of organometallic cobalt-catalyzed C–H activation is reviewed until November 2015.

Catalytic Enantioselective Transformations Involving C-H Bond Cleavage by Transition-Metal Complexes.

Abstract: The development of new methods for the direct functionalization of unactivated C–H bonds is ushering in a paradigm shift in the field of retrosynthetic analysis. In particular, the catalytic enantioselective functionalization of C–H bonds represents a highly atom- and step-economic approach toward the generation of structural complexity. However, as a result of their ubiquity and low reactivity, controlling both the chemo- and stereoselectivity of such processes constitutes a significant challenge. Herein we comprehensively review all asymmetric transition-metal-catalyzed methodologies that are believed to proceed via an inner-sphere-type mechanism, with an emphasis on the nature of stereochemistry generation. Our analysis serves to document the considerable and rapid progress within in the field, while also highlighting limitations of current methods.