Electrochemical Oxidation of Metal Dialkyl Phosphites and Their Reaction with Halogens

Electrochemical oxidation of sodium dialkyl phosphites with alkyl radicals of normal structure leads to formation of tetraalkyl pyrophosphites as the main products, while electrochemical oxidation of litium dialkyl phosphites and sodium salts with branched alkyl radicals yields tetraalkyl hypophosphates. The reaction of metal dialkyl phosphites with halogens leads to analogous results

Reactions of trialkylphosphine radical cations with cycloalkenes

Electrochemical oxidation of tertiary aliphatic phosphines in the presence of cyclohexene or cyclopentene yields isomeric cycloalkenylphosphonium salts with different positions of the double bond in the cycloalkenyl substituent relative to the phosphonium group

Radical Cations of Phosphorous Amides in Reactions with Alkenes

Electrochemical oxidation of diethyl diethylphosphoramidite and ethyl tetraethylphosphorodiamidite in the presence of alkenes results in formation of amido(1-alkenyl)- and amido(2-alkenyl)phosphonates. Under the same conditions, hexaethylphosphorous triamide forms a dodecaethylhexaaminodiphosphonium salt. Electrochemical oxidation of the above phosphoramidites and -diamidites in the presence of diethyl hydrogen phosphite or O,O-dibutyl hydrogen thiophosphite and an alkene involves addition of (RO)2P(O,S)H at the multiple bond and yields a different ratio of isomeric mono- and diamidoalkenylphosphonates

Electrochemical and Catalytic Initiation of Triethyl Phosphite Addition to Cyclohexanone

Electrochemical oxidation of triethyl phosphite in the presence of cyclohexanone results in a mixture of three products: diethyl(1-ethoxycyclohexyl)phosphonate, diethyl phosphonate, and 2-(1-cyclohexenyl)cylcyclohexanone. These products are formed through the stage on the anode synthesis of quasiphosphonium salts, which initiate addition of triethyl phosphite to cyclohexanone and condensation of cyclohexanone. The fact that quasiphosphonium salts catalyze addition of the phosphite to the ketone was proved by independent experiment

Mechanism of Electrochemical Synthesis of Phosphonium and Quasiphosphonium Salts

The radical cations generated on the anode in the course of electrochemical oxidation of tripropylphosphine in the presence of toluene and water are established to react with the aromatic compound and initial phosphine rather than with water molecules. The experimental findings made it possible to propose a new method of electrochemical synthesis of arylphosphonium salts. The electrochemical synthesis of quasiphosphonium salts, performed by electrochemical oxidation of tertiary phosphines in the presence of alcohols, amines, phenols, thiols, and disulfides, is assumed to involve a diphosphonium intermediate, while the synthesis of arylphosphonium cations proceeds by the mechanism of free-radical aromatic substitution

High energy hadrons in EAS at mountain altitude

An extensive simulation has been carried out to estimate the physical interpretation of dynamical factors such as , in terms of high energy interaction features, concentrated in the present analysis on the average transverse momentum. It appears that the large enhancement observed for versus primary energy, suggesting in earliest analysis a significant rise of with energy, is only the result of the limited resolution of the detectors and remains in agreement with a wide range of models used in simulations.Comment: 13 pages, 6 PostScript figures, LaTeX Subm. to JPhys

Free-Radical Phosphorylation of Olefins Initiated by Anodic Oxidation

Electrochemical oxidation of lithium and sodium dialkyl phosphites generates dialkyl phosphonyl radicals, which initiate chain free-radical addition of dialkyl phosphites across the alkene multiple bond to form alkyl(cycloalkyl)phosphonates. Alkyl(cycloalkyl)phosphonates are formed simultaneously owing to anodic oxidation of adsorbed primary radical adducts of phosphonyl radical and alkene molecule to give the carbenium cation, followed by deprotonation of the latter

Electrochemically induced phosphorylation of alkenes

The processes of electrochemical phosphorylation of alkenes were investigated. It was found that anodically generated radical-cations of trialkyl phosphites, dialkyl trimethylsilyl phosphites, mono-and diamidophosphites were added to olefin molecules to give unsaturated alkenephosphonates. The anodic oxidation of tetraalkyl pyrophosphites proceeds with disintegration of initial radical-cations and leads to mixture alkane-and alkenephosphonates. Greater amounts of alkanephosphonates were formed during anodic oxidation of sodium (or lithium) dialkyl phosphites in the presence of alkenes. © 1997 Published by Elsevier Science Ltd

Yield, plasticity, stability and homeostasis of spring barley cultivars in the Non-Black Earth Region

Background. The expansion of agrometeorological factors negatively affecting the productivity of spring barley has oriented plant breeders towards developing adaptable forms capable of realizing their genetic potential for higher yield under unfavorable conditions. Applying several methods of statistical data analysis helps to perform a more accurate assessment of the material differentiated according to its adaptability indicators. The objective of this study was to assess the adaptability of spring barley cultivars on the basis of their yield, plasticity, stability and homeostasis.Materials and methods. The resulting data were obtained for ten spring barley cultivars developed at Nemchinovka FRC.Results. High yield potential of more than 8.5 t/ha was disclosed in barley cultivars ‘Yaromir’, ‘Nur’, ‘Nadezhny’, ‘Sudar’, ‘Zlatoyar’ and ‘Znatny’. Cvs. ‘Luboyar’, ‘Nadezhny’ and ‘Rafael’ showed the highest adaptability to the worst growing conditions (4.65–5.04 t/ha) as well as high adaptive and compensatory ability. Cvs. ‘Sudar’, ‘Nur’ and ‘Zlatoyar’ were identified for high environmental plasticity (Cvi = 24.1–25.9%; bi = 1.02–1.16; σ = 1.52–1.59), while ‘Lyuboyar’, ‘Znatny’ and ‘Vladimir’ for their stability parameters (S2di = 0.05–0.19; σ2CACi = 1.60–1.78; σ2(G×E)gi = 0.05–0.15). The highest values of homeostasis (BVGi = 3.45– 3.53; CSLi = 138.7–139.4; Homi = 9.02–9.85) were registered for cvs. ‘Rafael’ and ‘Lyuboyar’. The calculated rating of the tested cultivars identified ‘Nadezhny’ as the best in productivity, while ‘Zlatoyar’ was the best in environmental plasticity. The highest levels of stability and homeostasis were recorded for cvs. ‘Rafael’ and ‘Lyuboyar’.Conclusion. Comprehensive assessment of productivity and adaptability indicators in the tested spring barley cultivars showed that ‘Lyuboyar’, ‘Nadezhny’, ‘Zlatoyar’ and ‘Rafael’ were the best under the conditions of the Non-Black Earth Region