Dialkyl Diselenides Research Articles

ChemInform Abstract: Reduction of Elemental Selenium by Samarium Diiodide: Selective Synthesis of Diorganyl Selenides and Diselenides.

The reduction of elemental selenium by samarium diiodide led to selective formation of selenolate anion species (Se2− and Se22−), the alkylation of which provided dialkyl selenides and diselenides, respectively, in excellent yields.

ChemInform Abstract: Synthesis of Substituted Glycerol Selenide Ethers under Microwave Irradiation.

Substituted glycerol selenide ethers are rapidly obtained in high yields and good regioselectivities by reducing dialkyl diselenides with sodium tetrahydroborate in a basic environment followed by reaction with glycidyl sulfide ether under microwave irradiation conditions.

ChemInform Abstract: Synthesis and Reactions of the Optically Active Dialkyl Diselenides from the Pinane Group.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

New chiral selenium electrophiles derived from functionalized terpenes

A convenient method for the synthesis of optically active dialkyl diselenides derived from bicyclic terpenes functionalized with hydroxy, etheral, sulfide, and selenide groups is described. The diselenides were used for a synthesis of chiral electrophilic selenium reagents, then in the asymmetric selenenylation of styrene and selenocyclization with o-allylphenol. The influence of nonbonding selenium-heteroatom interactions in the generated organoselenium electrophiles on the stereoselectivity of an addition reaction has been investigated. Calculations by a DFT method on a B3LYP (6–311G ( d)) level, confirmed the existence of nonbonded selenium–heteroatom interactions in the investigated systems.

Synthesis and Reactions of the Optically Active Dialkyl Diselenides from the Pinane Group

A convenient method of synthesis of the optically active dialkyl diselenides from the pinane group is described. The 3-hydroxy and 3-alkoxy derivatives of bis(cis-myrtanyl) diselenide have been obtained. The influence of a structure of the resulting diselenides on the diastereomeric excess of the methoxyselenenylation reaction and the selenocyclization have been investigated. Keywords: Asymmetric synthesis, Diselenides, Selenium, Terpenoids

ChemInform Abstract: Reductive Selenation of Aliphatic Ketones to Dialkyl Diselenides with Se—CO—H2O under Atmospheric Pressure.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Ring opening of unprotected aziridines by zinc selenolates in a biphasic system

A set of chiral β-seleno amines were prepared by the ring-opening reaction of unprotected aziridines. Under acid conditions diaryl or dialkyl diselenides were reduced by zinc and treated with unprotected aziridines to produce the desired products in good yields. Chiral β-telluro amine was also obtained using this method.

Synthesis and reactions of enantiomerically pure dialkyl diselenides from the p-menthane group

A convenient route for the synthesis of optically active dialkyl diselenides from the p-menthane system utilizing a reaction of alkyl tosylates and chlorides with sodium diselenide is reported. The diselenides obtained have been used for asymmetric methoxyselenenylation of styrene. Quantum chemical calculations of the chair conformers stability of the terpeneselenenyl bromides from the p-menthane group have also been carried out using density functional theory (DFT, at the B3LYP/6-311G(d) level). The influence of the diselenides structure on the stereoselectivity in the methoxyselenenylation reaction is also discussed.

Dialkyl dichalcogen cations

One electron oxidation of dialkyl diselenides and ditellurides is achieved with NO(+)CF(3)SO(3)(-). According to ab initio calculations the radical cations have a trans stucture. In the solid state they dimerize to rectangular units [R-Te](4)(2+) and [R-Se](4)(2+). The long SeSe and TeTe bond is obviously due to a pi*-pi* interaction.

Synthesis of 1,1′-Binaphthyl-2,2′-diyl Phosphoroselenoic Ammonium Salts and Their Conversion to Optically Active Dialkyl Diselenides

Abstract Optically pure phosphoroselenoyl chloride reacted with Et3N in the presence of H2O to give a phosphoroselenoic tertiary ammonium salt. Formation of the salt was confirmed by X-ray molecular structure analysis. The quaternary ammonium salt was prepared by reacting phosphoroselenoic acid O-2-silylethyl ester with Bu4NF. The alkylation of tertiary ammonium salt with racemic alkyl halides gave phosphoroselenoic acid Se-esters as diastereomeric mixtures. The cleavage of Se-esters with Bu4NF gave optically active dialkyl diselenides.

Efficient synthesis of diorganyl selenides via cleavage of Se–Se bond of diselenides by indium(III) catalyst and zinc

A simple and efficient procedure for the synthesis of unsymmetrical diorganyl selenides from an one-pot indium(III) catalyzed procedure, in the presence of zinc, has been developed. Various organic halides and even the unreactive organic chlorides underwent the reaction efficiently. Also diaryl and dialkyl diselenides underwent the coupling reaction.

Syntheses and Reactions of New Optically Active Terpene Dialkyl Diselenides

AbstractThe reaction of sodium diselenide with optically active alkyl tosylates or chlorides is found to be a useful method for the synthesis of optically active dialkyl diselenides. Optically active monoterpene diselenides derived from menthane, carane, pinane, and bornane systems have been obtained. The influence of the terpene fragment of the obtained diselenides on the diastereomeric excess of the methoxyselenylation products has been investigated. The best result for methoxyselenylation was observed for (–)‐diisopinocamphyl diselenide. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

Convenient Route to Dialkyl Diselenides from Alkyl Tosylates. Synthesis of Di(cis‐myrtanyl) Diselenide.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Condition‐Driven Selective Syntheses of Dialkyl Diselenides Involving Elemental Selenium and Sodium Borohydride.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Convenient route to dialkyl diselenides from alkyl tosylates. Synthesis of di( cis-myrtanyl) diselenide

A one-step method for the synthesis of dialkyl diselenides, by reaction of alkyl tosylates with sodium diselenide is described. Three variants of the synthesis, using as an example the preparation of optically active di( cis-myrtanyl) diselenide, are compared.

Condition-Driven Selective Syntheses of Dialkyl Diselenides Involving Elemental Selenium and Sodium Borohydride

Dialkyl diselenides have been prepared from alkyl halides, sodium borohydride and elemental selenium using two different methods. One of them involves the intermediate formation of diselenide dianion equivalent ( - SeSe - ).

Synthesis of New Diaryl and Dialkyl Diselenides as Potential Virucides and Antimicrobials.

AbstractFor Abstract see ChemInform Abstract in Full Text.

Synthesis of diselenides and selenides from elemental selenium

Sodium hydride is able to reduce elemental selenium to sodium diselenide (Na 2Se 2), but not to sodium selenide (Na 2Se). Dialkyl diselenides and even dialkyl selenides, including unsymmetrical dialkyl selenides, can be nevertheless synthesized using the proper Se/NaH ratio (1/1 or 1/2).

Syn addition of dialkyl diselenide to phenylacetylene in the presence of tin tetrachloride

The tin tetrachloride-mediated reaction of dialkyl diselenides with phenylacetylene proceeds as syn addition to afford' 2a,b.

Insertion of Elemental Sulfur into the Se-Se Bond of Diorganyl Diselenides. Synthesis of Bis-alkyl(seleno) Polysulfides

Reaction of dialkyl diselenides R2Se2 (R = Me, n-Bu) with sulfur at room temperature in the presence of the catalytic system DMSO-Na2S·9H2O-triethylbenzylammonium chloride, as well as at 55-60°C in the presence or in the absence of catalysts leads to the insertion of from one to six atoms of sulfur into the Se-Se bond. Bis(methylseleno) polysulfides MeSeSnSeMe with n = 5-6 gradually liberate sulfur on keeping. Dibutyl diselenide is less active than dimethyl diselenide, and diphenyl diselenide does not react with sulfur in boiling carbon disulfide. At 55-60°C a small portion of selenium in dialkyl diselenides passes into unreacted sulfur which is indicative of cleavage of the C-Se bonds in bis(methylseleno) polysulfides.