- Acridine Orange Hemi(Zinc Chloride) Salt as a Lewis Acid-Photoredox Hybrid Catalyst for the Generation of α-Carbonyl Radicals
-
A readily accessible organic-inorganic hybrid catalyst is reported for the reductive fragmentation of α-halocarbonyl compounds. The robust hybrid catalyst is a self-stabilizing combination of ZnCl2 Lewis acid and acridine orange as the photoactive organic dye. Mechanistic specifics of this hybrid catalyst have been studied in detail using both photophysical and electrochemical experiments. A systematic study enabled the discovery of the appropriate Lewis acid for the effective LUMO stabilization of α-halocarbonyl compounds and thereby lowering of reduction potential within the range of a standard organic dye. This strategy resolves the issues like dehalogenative hydrogenation or homo-coupling of alkyl radicals by guiding the photoredox cycle through an oxidative quenching pathway. The cooperativity between the photoactive organic dye and the Lewis acid counterparts empowers functionalization with a wide range of coupling partners through efficient and controlled generation of alkyl radicals and serves as an appropriate alternative to the expensive late transition metal-based photocatalysts. To demonstrate the application potential of this cooperative catalytic system, four different synthetic transformations of α-carbonyl bromides were explored with broad substrate scopes.
- Das, Sanju,De Sarkar, Suman,Mandal, Tanumoy
-
supporting information
(2021/12/10)
-
- Methyl Radical Initiated Kharasch and Related Reactions
-
An improved procedure to run halogen atom and related chalcogen group transfer radical additions is reported. The procedure relies on the thermal decomposition of di-tert-butylhyponitrite (DTBHN), a safer alternative to the explosive diacetyl peroxide, to produce highly reactive methyl radicals that can initiate the chain process. This mode of initiation generates byproducts that are either gaseous (N2) or volatile (acetone and methyl halide) thereby facilitating greatly product purification by either flash column chromatography or distillation. In addition, remarkably simple and mild reaction conditions (refluxing EtOAc during 30 minutes under normal atmosphere) and a low excess of the radical precursor reagent (2 equivalents) make this protocol particularly attractive for preparative synthetic applications. This initiation procedure has been demonstrated with a broad scope since it works efficiently to add a range of electrophilic radicals generated from iodides, bromides, selenides and xanthates over a range of unactivated terminal alkenes. A diverse set of radical trap substrates exemplifies a broad functional group tolerance. Finally, di-tert-butyl peroxyoxalate (DTBPO) is also demonstrated as alternative source of tert-butoxyl radicals to initiate these reactions under identical conditions which gives gaseous by-products (CO2). (Figure presented.).
- Tappin, Nicholas D. C.,Renaud, Philippe
-
supporting information
p. 275 - 282
(2020/12/07)
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- Air-stable binuclear Titanium(IV) salophen perfluorobutanesulfonate with zinc power catalytic system and its application to C–S and C–Se bond formation
-
An air-stable μ-oxo-bridged binuclear Lewis acid of titanium(IV) salophen perfluorobutanesulfonate [{Ti(salophen)H2O}2O][OSO2C4F9]2 (1) was successfully synthesized by the reaction of TiIV(salophen)Cl2 with AgOSO2C4F9 and characterized by techniques such as IR, NMR and HRMS. This complex was stable open to air over a year, and exhibited good thermal stability and high solubility in polar organic solvents. The complex also had relatively strong acidity with a strength of 0.8 Ho ≤ 3.3, and showed high catalytic efficiency towards various C–S and C–Se bond formations in the presence of zinc power. This catalytic system affords a mild and efficient approach to synthesis of thio- and selenoesters, α-arylthio- and seleno-carbonyl compounds, and thio- and selenoethers.
- Wang, Lingxiao,Qiao, Jie,Wei, Jiancong,Liang, Zhiwu,Xu, Xinhua,Li, Ningbo
-
-
- O-(tert-butyl) Se-phenyl selenocarbonate: A convenient, bench-stable and metal-free precursor of benzeneselenol
-
A study by our laboratory shows that air, light and moisture stable O-(tert-butyl) Se-phenyl selenocarbonate could be employed as a safer, practical and efficient alternative to generate “in situ” benzeneselenol or benzeneselenolate anion under different and transition metal-free conditions. This procedure seems to be of general application since the nucleophilic selenium species obtained can be trapped by electrophiles such as alkyl halides, epoxides and electron-deficient alkenes and alkynes under different reaction conditions.
- Temperini, Andrea,Siciliano, Carlo
-
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- Rhodium-Catalyzed Carbene Transfer Reactions for Sigmatropic Rearrangement Reactions of Selenium Ylides
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The rearrangement of selenium ylides is even today almost unexplored, although it would provide access to important organoselenium compounds with broad downstream applications. In this report, the first systematic study of sigmatropic rearrangement reactions of selenium ylides using a simple rhodium catalyst with catalyst loadings as low as 0.01 mol % is described. Selenium oxide pyrolysis of the rearrangement products gives access to important 1,1-disubstituted butadienes.
- Jana, Sripati,Koenigs, Rene M.
-
supporting information
p. 3653 - 3657
(2019/05/24)
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- Rhodium-Catalyzed Rearrangement of S/Se-Ylides for the Synthesis of Substituted Vinylogous Carbonates
-
An efficient rhodium-catalyzed unprecedented oxa-[2,3]-sigmatropic rearrangement of sulfur ylide derived from α-thioesters/ketones and diazo carbonyl compounds has been accomplished for the synthesis of various sulfur-tethered vinylogous carbonates in good to excellent yields. Important features of the developed reaction include wide functional group tolerance, excellent chemo- and regioselectivity, and efficient rearrangement involving the carbonyl motif. The present reaction also equally works well with α-selenoesters for the synthesis of seleno-containing vinylogous carbonates.
- Reddy, Angula Chandra Shekar,Anbarasan, Pazhamalai
-
supporting information
p. 9965 - 9969
(2019/12/24)
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- Preparation method and application of novel ionic binuclear Schiff base titanium complex
-
The invention provides a preparation method of a novel ionic binuclear Schiff base titanium complex and a synthetic method of applying the novel ionic binuclear Schiff base titanium complex to catalyze zinc powder and reduce disulfide or selenide to prepare sulfo(seleno) ester and dissymmetric sulfoether(selenide). The complex is a cationic binuclear Schiff base titanium complex, wherein titaniumatoms are bridged by oxygen atoms and are coordinated with a Schiff base ligand and a hydrone, and an ionic bond is formed by a cation part and an anion part of whole Schiff base titanium. The ionic binuclear Schiff base titanium complex is used as a catalyst, the zinc powder is used as a reducer, the disulfide(selenide) can be reduced and fractured, and the disulfide(selenide) can further and respectively react with anhydride, an alpha-bromo carbonyl compound and bromoalkane to prepare the sulfo(seleno) ester and the dissymmetric sulfoether(selenide). According to the preparation method provided by the invention, the defects that traditional lewis acid halide is deliquescent, an absolute solvent is used, conditions are strict and the like are overcome; an effective path for reducing the disulfide or selenide to prepare the sulfo(seleno) ester and the dissymmetric sulfoether(selenide) is provided, and the preparation method has the advantages of high yield, simpleness in operation andthe like.
- -
-
Paragraph 0071; 0072
(2018/04/03)
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- Light-mediated total synthesis of 17-deoxyprovidencin
-
An asymmetric synthesis of the diterpenoid 17-deoxyprovidencin is described. Key steps include an aldol addition, a base-catalyzed Wipf-type furan formation, a Z-selective ring-closing metathesis for macrocyclization, a photochemical E/Z isomerization to a highly strained and conformationally restricted ring system, and the stereoselective formation of two epoxides on the ring. Photochemistry is the key: An asymmetric synthesis of the diterpenoid 17-deoxyprovidencin is described. Key steps include an aldol addition, a base-catalyzed Wipf-type furan formation, a Z-selective ring-closing metathesis for macrocyclization, a photoinduced Z/E isomerization to a highly strained conformationally restricted ring system, and the stereoselective formation of two epoxides on the macrocycle.
- Toelle, Nina,Weinstabl, Harald,Gaich, Tanja,Mulzer, Johann
-
supporting information
p. 3859 - 3862
(2014/05/06)
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- Ionic liquid/PPh3 promoted cleavage of diphenyl disulfide and diselenide: A straight-forward metal-free one-pot route to the synthesis of unsymmetrical sulfides and selenides
-
A metal-free cleavage of diphenyl disulfide and diphenyl diselenide has been achieved using ionic liquid/triphenyl phosphine (PPh3) and a convenient protocol for the one-pot synthesis of unsymmetrical sulfides and selenides by condensing 'in situ' generated thiolate or selenate anion with alkyl halides has been developed. In addition, 1,4-conjugate addition of the generated thiolate anions to activated alkenes has also been demonstrated. The ionic liquid, 1-methyl-3-pentyl imidazolium bromide, [pmIm]Br plays a crucial role in promoting the course of the reactions and shows superior activity and selectivity compared to other solvents. The [pmIm]Br has been reused for at least five times without appreciable loss of activity.
- Banerjee, Subhash,Adak, Laksmikanta,Ranu, Brindaban C.
-
supporting information; experimental part
p. 2149 - 2152
(2012/05/05)
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- On the reactivity of indium(III) benzenechalcogenolates (chalcogen = sulfur and selenium) towards organyl halides for the synthesis of organyl phenyl chalcogenides
-
The reactivity of indium(III) benzenechalcogenolates (chalcogen = sulfur, selenium) towards organyl halides (organyl = alkyl, allyl, benzyl, acyl) was examined. A practical one-pot method to prepare organyl phenyl chalcogenides indium metal and diphenyl dichalcogenide was found. The coupling is fairly broad in scope and generally works better organyl halides capable to produce stable carbocations.
- Peppe, Clovis,Borges De Castro, Lierson
-
experimental part
p. 678 - 683
(2009/10/30)
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- Convenient preparation of benzylseleno- and phenylselenoalkanoic acids: Reagents for synthesis of organoselenium compounds
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An efficient and operationally simple route to benzylseleno- and phenylselenoalkanoic acids from ethyl benzyl/phenylselenoalkanoates is described. This involves preparation of ethyl benzyl/phenylselenoalkanoates as substrates by reaction of dibenzyl/diphenyl diselenide and sodium borohydride with ethyl chloroalkanoates in ethanol followed by basic hydrolysis and subsequent acidification. Copyright Taylor & Francis Group, LLC.
- Bhalla, Aman,Sharma, Sitansh,Bhasin, Kuldip K.,Bari, Shamsher S.
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p. 783 - 793
(2007/10/03)
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- Zinc-mediated cleavage of diselenides: A novel synthesis of unsymmetrical diorganyl selenides in aqueous media
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A convenient synthetic method has been developed for the preparation of unsymmetrical selenides through a one-pot zinc-mediated reaction of diselenides and active organic halides in aqueous media.
- Movassagh, Barahman,Shamsipoor, Mojgan
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p. 121 - 122
(2007/10/03)
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- A novel synthesis of unsymmetrical selenides via the cleavage of Se-Se bond by Sm/cat.CoCl2 system
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Promoted by Sm/cat. CoCl2 system, the Se-Se bond of diaryldiselenides was easily cleaved to form a "living" intermediate, which reacted readily with alkyl halides to afford unsymmetrical alkylarylselenides in good yields under mild and neutral reaction conditions.
- Chen, Rener,Su, Weike,Zhong, Weihui
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p. 620 - 621
(2007/10/03)
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- Reductive cleavage of Se-Se bond by Sm/NiCl2 or Sm/NiCl 2.6H2O system: A novel preparation of unsymmetrical aryl selenides
-
The Sm/NiCl2 or Sm/NiCl2.6H2O system promoted diarylselenides to react with alkyl halides to afford unsymmetrical aryl selenides in good yields under mild and neutral conditions.
- Chen,Su
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p. 958 - 959
(2007/10/03)
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- Fluorinations of α-seleno carboxylic acid derivatives with hypervalent (difluoroiodo)toluene
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A very efficient synthesis of (difluoroiodo)toluene avoiding the use of elemental chlorine and elemental fluorine is described. We have fluorinated a series of α-acceptor substituted selenides using (difluoroiodo)toluene. The reactions are usually very clean and under the reaction conditions no further oxidized products are observed. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
- Arrica, Maria A.,Wirth, Thomas
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p. 395 - 403
(2007/10/03)
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- Indium(I) iodide-promoted cleavage of diaryl diselenides and disulfides and subsequent condensation with alkyl or acyl halides. One-pot efficient synthesis of diorganyl selenides, sulfides, selenoesters, and thioesters
-
Diphenyl diselenides and disulfides undergo facile cleavages by indium(I) iodide and the corresponding generated selenate and thiolate anions condense in situ with alkyl or acyl halides present in the reaction mixture. Thus, a simple, efficient, and general procedure has been developed for the synthesis of unsymmetrical diorganyl selenides, sulfides (thioethers), selenoesters, and thioesters by this one-pot reaction at room temperature.
- Ranu, Brindaban C.,Mandal, Tanmay
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p. 5793 - 5795
(2007/10/03)
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- Electrosynthesis of ethyl α, α-difluoro-α-(phenylseleno)acetate and its photochemical synthetic application
-
Anodic fluorination of ethyl α-fluoro-α-(phenylseleno) acetate was successfully carried out to give ethyl α,α -difluoro-α-(phenylseleno)acetate in high yield. Photolysis of the difluorinated product in the presence of various olefins provided regioselective difluorometylene adducts in good to moderate total yields. The reaction involves phenylselenyl transfer at the early stage followed by the elimination of a phenylselenyl group from the adducts once formed to provide the unsaturated and saturated difluoromethylene products.
- Murakami, Satoru,Ishii, Hideki,Fuchigami, Toshio
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p. 609 - 614
(2007/10/03)
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- Indium(I) iodide-mediated cleavage of diphenyl diselenide. An efficient one-pot procedure for the synthesis of unsymmetrical diorganyl selenides
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(Matrix presented) A simple and efficient procedure has been developed for the synthesis of unsymmetrical diorganyl selenides through a one-pot indium(I) iodide-mediated reaction of alkyl halide and diphenyl diselenide in methylene chloride at room temperature.
- Ranu, Brindaban C.,Mandal, Tanmay,Samanta, Sampak
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p. 1439 - 1441
(2007/10/03)
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- Phenyl tributylstannyl selenide as a promising reagent for introducion of the phenylseleno group
-
A new synthetic method of organoselenium compounds has been developed. When phenyl tributylstannyl selenide (PhSeSnBu3) was allowed to react with acyl or aroyl chlorides in the presence of a catalytic amount of a palladium complex such as Pd(PPh3)4, Se-phenyl selenol esters were obtained in moderate to good yields. Similarly, the palladium complex catalyzed the reaction of PhSeSnBu3 with α-halo carbonyl compounds to afford the corresponding α-phenyseleno carbonyl compounds in moderate yields.
- Nishiyama, Yutaka,Kawamatsu, Hiroaki,Funato, Saori,Tokunaga, Keiji,Sonoda, Noboru
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p. 3599 - 3602
(2007/10/03)
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- Synthesis of chalcogenides using indium intermediates in aqueous media
-
Selenides and vinylic selenides were synthesized from their corresponding organic halides and alkynes in aqueous media using indium metal.
- Galindo, Andréa C.,Oliveira, Juliana M.,Barboza, Maria A. G.,Gon?alves, Simone M. C.,Menezes, Paulo H.
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p. 129 - 140
(2007/10/03)
-
- General synthesis of alkyl phenyl selenides from organic halides mediated by zinc in aqueous medium
-
Organic halides of different structural types react with diphenyl diselenide and zinc dust in aqueous medium to give alkyl phenyl selenides. Benzylic and allylic bromides, α-bromoesters, acids and ketones and some primary alkyl iodides produce high yields even under acidic conditions. Less reactive halides need basic medium. The reaction proceeds equally well in the presence of various unprotected functional groups. Control experiments support a SH2 mechanism via alkyl radicals.
- Bieber, Lothar W.,De Sá, Ana C.P.F.,Menezes, Paulo H.,Gon?alves, Simone M.C.
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p. 4597 - 4599
(2007/10/03)
-
- Convenient one-pot synthesis of α-selenonitriles, α-selenoesters and asymmetrical selenides by a Sm/ZnCl2 system in DMF-H2O
-
α-Selenonitriles, α-selenoesters, and asymmetrical selenides can be readily obtained from the one-pot reaction of diselenides and active organic halides by a Sm/ZnCl2 system in DMF-H2O.
- Guo,Zheng,Zhang
-
p. 160 - 161
(2007/10/03)
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- PhSeSiR3-catalyzed group transfer radical reactions
-
A novel design for initiating radical-based chemistry in a catalytic fashion is described. The design of the concept is based on the phenylselenyl group transfer reaction from alkyl phenyl selenides by utilizing PhSeSiR3 (1) as a catalytic reagent. The reaction is initiated by the homolytic cleavage of -C-Se- bond of an alkyl phenyl selenide by the in situ generated alkylsilyl radical (R3Si), obtained by the mesolysis of PhSeSiR3](·)- (1(·)-). The oxidative dimerization of counteranion PhSe- to PhSeSePh functions as radical terminator. The generation of 1(·)- is achieved by the photoinduced electron transfer (PET) promoted reductive activation of 1 through a photosystem comprising of a visible-light (410 nm)-absorbing electron rich DMA as an electron donor and ascorbic acid as a co-oxidant (Figure 1). The optimum mole ratio between the catalyst 1 and alkyl phenyl selenides for successful reaction is established to be 1:10. The generality of the concept is demonstrated by carrying out variety of radical reactions such as cyclization (10, 15-18), intermolecular addition (25), and tandem annulations (32).
- Pandey, Ganesh,Rao,Nageshwar Rao
-
p. 4309 - 4314
(2007/10/03)
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- Synthesis of allyl-type selenides and α -selenoesters in aqueous media promoted by cadmium
-
Promoted by metallic cadmium which was produced by reduction of CdCl2 · H2O with samarium in situ, allyl bromide and α -bromocarboxylates react with diorgano diselenides in aqueous solutions to give allylic-type selenides and α -selenocarboxylates in moderate to good yields.
- Zheng, Yunfa,Bao, Weiliang,Zhang, Yongmin
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p. 1731 - 1736
(2007/10/03)
-
- Preparation and oxidation of α-phenylselanyl esters
-
Alkylation and selenenylation of selenium-stabilized ester enolates have allowed the preparation of α-phenylselanyl esters 5, 7, 8 and of α,α-bis(phenylselanyl)esters 6, respectively. The competitive selenophilic reaction, leading to an allylic phenylselenide 9, was avoided in the presence of HMPA. α-phenylselanyl α,β-unsaturated esters 15 were prepared by oxidation of compounds 6 and dehydrohalogenation of β-chloroesters 17. Some other transformations: oxidation, transesterification and Grignard reaction were also studied. H2O2 oxidation of Z-esters 15 has led to stable E-α-seleninyl esters 20. (C) 2000 Elsevier Science Ltd.
- Lebarillier, Loic,Outurquin, Francis,Paulmier, Claude
-
p. 7483 - 7493
(2007/10/03)
-
- Synthesis and reactivity of α and β-chloro-α-phenylselanyl esters
-
Thermal decomposition of the dichloro-adducts derived from α-phenylselanylesters 1, 2 and 4 has been studied. N-Chloro-succinimide treatment of esters 2 was an efficient preparative method for α-chloro-α-phenylselanylesters 10 and α-chloro-α,β-unsaturated esters 11. Some transformations of esters 10 were achieved, α,β-Dichloro-α-phenylselanylesters 22 were prepared from β-chloro-α-phenylselanylesters 5 or by decomposition of the dichloroselenuranes 21 derived from esters 4. (C) 2000 Elsevier Science Ltd.
- Lebarillier, Loic,Outurquin, Francis,Paulmier, Claude
-
p. 7495 - 7502
(2007/10/03)
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- Reductive Cleavage of the Se-Se Bond by the Sm-Me3SiCl-H2O System: Preparation of Unsymmetrical Phenyl Selenides
-
The reduction of diphenyl diselenide by the Sm-Me3SiCl-H2O system led to a selenide anion. This 'living' species reacted with organic halides, epoxides, α,β-unsaturated esters and α,β-unsaturated nitrtles to afford unsymmetrical phenylselenides in good yields under mild and neutral conditions.
- Wang, Lei,Zhang, Yongmin
-
p. 598 - 599
(2007/10/03)
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- Insertion of elemental selenium into zinc carbon bond and application in synthesis of α-selenocarbonyl compound
-
Selenium inserted into the zinc carbon bond of alkyl and aryl zinc halides to form the corresponding the zinc alkyl and arylselnoates. They reacted in THF-HMPA with α-bromo carbonyl compounds to afford the α- selenocarbonyl compounds in high yields.
- Huang, Xian,Xu, Xin-Hua
-
p. 807 - 811
(2007/10/03)
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- Organometallic Reaction in Aqueous Media. Synthesis of α-Selenoesters by Reactions of α-Bromoesters with Diselenides Promoted by Metallic Tin
-
In aqueous conditions α-bromoesters can react with diselenides by metallic tin to give α-selenoesters in moderate to good yields.
- Qian, Weixing,Bao, Weiliang,Zhang, Yongmin
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p. 393 - 394
(2007/10/03)
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- Rate Constants for Chalcogen Group Transfers in Bimolecular Substitution Reactions with Primary Alkyl Radicals
-
Rate constants for group transfers of the MeS, PhS, PhSe, and PhTe groups from chalcogen-substituted acetate, acetonitrile, malonate, and malononitrile compounds, from N-(phenylthio)phthalimide and from Me2S2 and Ph2S2 to primary alkyl radicals, have been determined by competition kinetics using PTOC esters as the radical precursors and competing trapping agents.Thio group transfers from malononitrile derivatives are marginally faster than the corresponding group transfer from the symmetrical disulfide, and the rate constant for PhSe group transfer from PhSeSePh isgreater than those from the derivatives studied here.Substituent effects suggest that the chalcogen transfer reactions may be concerted.For three cases in which direct comparisons can be made, the rate constants for reactions of phenylchalcogenides are approximately equal to those for halogen atom transfer when the chalcogen and halide are in the same row of the periodic table and the radical resulting from displacement is the same.The rate constants reported in this work will be useful for the rational design of synthetic schemes based on homolytic group transfer chemistry.
- Curran, Dennis P.,Martin-Esker, Amanda A.,Ko, Sung-Bo,Newcomb, Martin
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p. 4691 - 4695
(2007/10/02)
-
- Synthesis of α-phenylchalcogeno acetic acids, ethyl-α-phenylchalcogeno acetates and ethyl-α-halo-α-phenylchalcogeno acetates
-
Reaction of phenyltellurolate or phenylselenolate anion with α-bromoacetic acid under phase transfer conditions using a liquid-solid system affords the α-phenyltelluro acetic acid and the α-phenylseleno acetic acid in 44 and 50percent yields respectively.
- Dabdoub, Miguel J.,Guerrero, Palimecio G.,Silveira, Claudio C.
-
-
- A convenient procedure for the preparation of organic selenides
-
Treatment of diphenyl diselenide with tributylphosphine in an alkaline medium forms phenylselenolate ion which converts alkyl halides, α,β-unsaturated ketones, and epoxides into alkyl selenides, (phenylseleno)alkenones, and β-(phenylseleno)alkanols, respe
- Sakakibara,Katsumata,Watanabe,Toru,Ueno
-
p. 377 - 379
(2007/10/02)
-
- REACTION OF BENZENESELENOL WITH TRI- AND TETRACHLOROETHYLENES UNDER CONDITIONS OF PHASE-TRANSFER CATALYSIS
-
The reaction of benzeneselenol with trichloroethylene in concentrated sodium hydroxide solution, catalyzed by ammonium salts, leads to Z-phenyl α,β-dichlorovinyl selenide with an equimolar ratio of the catalyst and the selenol or to a mixture of the Z and E isomers with a ratio of 1:10.In addition to the expected trichlorovinyl selenide PhSeCCl=CCl2, the analogous reaction with tetrachloroethylene also gives a mixture of the Z and E isomers of α,β-dichlorovinyl selenides and, in addition, 1,2-bis(phenylseleno)-1,2-dichloroethylene PhSeCCl=CClSePh.If trialkylbenzylammonium chlorides R3PhCH2N(1+)*Cl(1-) are used as catalyst, phenyl benzyl selenide PhSeCH2Ph is formed as a side product.The results of the reaction in the case of trichloroethylene are explained by the addition of the selenolate ion to the CClCCl, generated from the trichloroethylene in situ, and isomerization of the initially formed Z-phenyl α,β-dichlorovinyl selenide to the thermodynamically more stable E isomer.In the case of tetrachloroethylene they are explained by the usual addition-elimination mechanism with the formation of trichlorovinyl selenide, accompanied by reductive dechlorination of the CCl2=CCl2 to CHCl=CCl2 by the selenolate and subsequent reaction of the selenolate with CHCl=CCl2.
- Martynov, A. V.,Mirskova, A. N.,Kalikhman, I. D.,Voronkov, M. G.
-
p. 454 - 462
(2007/10/02)
-
- Relative Reactivities of Various Sulfides, Selenides and Halides Towards SH2 Attack by Tributyltin Radicals
-
The order of reactivity towards SH2 attack by tributyltin radicals on various groups X in four different molecular environments (RCO2CH2X, RCH2OCH2X, XCH2CO2Et and RCH2X) has been found by competition experiments to be Br > PhSe > Cl > p-CNC6H4S > PhS > p-MeC6H4S > MeS.The mechanism of the reaction of chloromethyl phenyl sulfide with alkoxides is discussed.
- Beckwith, Athelstan L. J.,Pigou, Paul E.
-
-
- REACTION OF ARACYL- AND ALKOXYCARBONYLMETHYLSELENONIUM SALTS WITH NUCLEOPHILIC REAGENTS
-
A method is proposed for the synthesis of α-methylselenium derivatives of aryl and heteryl methyl ketones and ethyl acetate by demethylation of readily available aracyl-, heteroacyl-, and methoxycarbonylmethylselenonium salts with triethylamine.It was established that triphenylphosphine cleaves dimethylphenacylselenonium bromide both at the Se-methyl and at the Se-CH2COPh bond (preferentially).Triphenylphosphine selenide is formed in this reaction in addition to the corresponding phosphonium salts.
- Magdesieva, N. N.,Kyandzhetsian, R. A.,Kirpichenok, M. A.,Chovnikova, N. G.
-
p. 2279 - 2284
(2007/10/02)
-
- Substitution Reactions of Thallous Thiophenoxide and Thallous Phenylselenide with Halogen-Bearing Substrates
-
Thallous thiophenoxide (1) and thallous selenide (2) were prepared by the action of either thallous ethoxide or thallous pentoxide on thiophenol and benzeneselenol.The reagents 1 and 2 reacted readily with aroyl and acyl halides, imidoyl chlorides, α-halo ketones, α-halo esters, α-halo lactones, α-halo carboxylic acids, allyl halides, alkyl halides, chlorotrimethylsilane, chloroacetonitrile, and N-chlorosuccinimide to give substitution products and varying amounts of diphenyl disulfide and diphenyl diselenide.The reactions were run as heterogeneous mixtures in ether.The origin of the diphenyl disulfide and diphenyl diselenide was homolytic cleavage of the thallium-sulfur or thallium-selenium bond, on the basis of the products derived from the reactions of N-chlorosuccinimide with 1 and 2.
- Detty, Michael R.,Wood, Gary P.
-
-