3278-38-4Relevant academic research and scientific papers
A Novel Method for the Direct Synthesis of Symmetrical and Unsymmetrical Sulfides and Disulfides from Aryl Halides and Ethyl Potassium Xanthogenate
Soleiman-Beigi,Arzehgar
, p. 986 - 992 (2018/02/09)
An efficient and new method for the synthesis of disulfides and sulfides via the reaction of aryl halides with ethyl potassium xanthogenate in the presence of MOF-199 is described. O -Ethyl- S -aryl carbonodithioate has a key role as an intermediate in this procedure; it was converted into symmetrical diaryl disulfides in DMF. Additionally, this could be applied to the synthesis of unsymmetrical aryl alkyl(aryl′) disulfides by the reaction with S -alkyl(aryl) sulfurothioates (Bunte salts) as well as unsymmetrical aryl alkyl(aryl′) sulfides in DMSO.
Copper nanoparticles supported on polyaniline-functionalized multiwall carbon nanotubes: An efficient and recyclable catalyst for synthesis of unsymmetric sulfides using potassium ethyl xanthogenate in water
Hajipour, Abdol R.,Jajarmi, Saeideh,Khorsandi, Zahra
, (2017/09/01)
A new and powerful polyaniline-functionalized carbon nanotube-supported copper(II) nanoparticle catalyst was successfully prepared and evaluated as a heterogeneous catalyst for the one-pot synthesis of unsymmetric thioethers by coupling of aryl, alkyl and benzyl halides using potassium ethyl xanthogenate as source of sulfur in water. All of these reactions gave the desired products in good to excellent yields. The catalyst is available, air-stable and can be reused several times without significant loss in its catalytic activity.
Synthesis of unsymmetrical sulfides using ethyl potassium xanthogenate and recyclable copper catalyst under ligand-free conditions
Akkilagunta, Vijay Kumar,Kakulapati, Rama Rao
supporting information; experimental part, p. 6819 - 6824 (2011/10/09)
The synthesis of unsymmetrical sulfides has been achieved in good to excellent yields with inexpensive ethyl potassium xanthogenate via cross-coupling reaction using recyclable CuO nanoparticles under ligand-free conditions.The copper oxide nanoparticles can be recovered and reused up to five cycles without loss of activity.
Kinetics and Mechanism of the Benzenethiolysis of O-Ethyl S-(2,4-Dinitrophenyl) and O-Ethyl S-(2,4,6-Trinitrophenyl) Dithiocarbonates and O-Methyl O-(2,4-Dinitrophenyl) Thiocarbonate
Castro, Enrique A.,Pavez, Paulina,Santos, Jose G.
, p. 9034 - 9039 (2007/10/03)
Reactions of O-ethyl 2,4-dinitrophenyl dithiocarbonate (EDNPDTC), O-ethyl 2,4,6-trinitrophenyl dithiocarbonate (ETNPDTC), and O-methyl O-(2,4-dinitrophenyl) thiocarbonate (MDNPTOC) with a series of benzenethiolate anions in aqueous solution, at 25.0 °C and an ionic strength of 0.2 M (KCl), are subjected to a kinetic investigation. Under excess benzenethiolate, these reactions obey pseudo-first-order kinetics and are first order in benzenethiolate. Nonetheless, similar reactant concentrations were used in the reactions of 4-nitrobenzenethiolate anion with the ethyl trinitrophenyl ester (ETNPDTC), which showed overall second-order kinetics. The nucleophilic rate constants (kN) are pH independent, except those for the reactions of ETNPDTC with the X-benzenethiolates with X = H, 4-Cl, and 3-Cl, which increase as pH decreases. The Bronsted-type plots (log kN vs pK a of benzenethiols) are linear with slopes β = 0.66 for the reactions of both ethyl dinitrophenyl ester (EDNPDTC) and ethyl trinitrophenyl ester (ETNPDTC) and β = 0.58 for those of the thiocarbonate ester (MDNPTOC). For the benzenethiolysis of MDNPTOC and EDNPDTC, no breaks were found in the Bronsted-type plots at pKa 4.1 and 3.4, respectively, consistent with concerted mechanisms. Benzenethiolysis of the ethyl trinitrophenyl ester (ETNPDTC) should also be concerted in view of the even more unstable tetrahedral intermediate that would have been formed had this reaction been stepwise. ETNPDTC is more reactive toward benzenethiolate anions than EDNPDTC due to the better leaving group involved in the former substrate. The kN values found for the reactions of EDNPDTC with benzenethiolates are larger than those obtained for the concerted reactions of the same substrate with isobasic phenoxide anions. This is explained by Pearson's hard and soft acids and bases principle. The concerted mechanism for the benzenethiolysis of MDNPTOC, in contrast to the stepwise mechanism found for the phenolysis of this substrate, is attributed to the greater kinetic instability of the hypothetical tetrahedral intermediate formed in the former reaction, due to the greater nucleofugality of ArS- compared with an isobasic ArO-. Benzenethiolates are more reactive toward MDNPTOC and EDNPDTC than the corresponding carbonate and thiolcarbonate, respectively. This is also in accordance with the HSAB principle, since benzenthiolates are relatively soft bases that prefer to bind to a relatively soft thiocarbonyl center rather than a relatively hard carbonyl center.
Reactions of arenediazonium tetrafluoroborates with inorganic and organic salts
Grishchuk,Gorbovoi,Zagrichuk,Ganushchak,Kudrik
, p. 1299 - 1303 (2007/10/03)
Arenediazonium tetrafluoroborates were reacted with inorganic and organic salts under anionarylation reaction conditions in the presence of strong nucleophiles (O,O-dimetyl dithiophosphate, N,N-diethyldithiocarbamate, and O-alkyl dithiocarbonate anions) and in the absence of catalysts [Cu(I) and Fe(II) salts] to obtain in high yields (dimethoxythiophosphinoylmercapto)-, (N,N-diethylthiocarbamoylmercapto)-, and (alkoxythiocarbonylmercapto)benzenes. The products of the reactions of arenediazonium tetrafluoroborates with potassium thiocyanate were identified and their compositions were determined. These reactions are proposed to occur by a radical mechanism, both under catalytic and noncatalytic conditions.
Hydrolysis and aminolysis of alkyl xanthate esters and cellulose analogues
Humeres, Eduardo,Soldi, Valdir,Klug, Marilene,Nunes, Mauricea,Oliveira, Celia M.S.,Barrie, Patrick J.
, p. 1050 - 1056 (2007/10/03)
The hydrolysis and aminolysis of a series of S-substituted O-alkylxanthate esters was studied in 20% v/v aqueous methanol at 35°C. The pH-rate profiles of the hydrolyses showed water and hydroxide-ion-catalyzed reactions. The reaction of 2,4-dinitrophenyl cellulose xanthate (CelXDNP) and p-nitrobenzyl cellulose xanthate (CelXNB) with polyalanine and lysozyme produced a covalent bond between the polypeptide and the cellulose matrix, as shown by solid-state 13C NMR. However, the nature of the bonding could not be identified. The reaction of nucleophiles (H2O, OH-, RNH2) and xanthic esters was consistent with an addition-elimination mechanism through a tetrahedral intermediate. Bronsted plots against the pKa of the nucleophile (βnu) or the nucleofuge of the substrate (βlg) were used to characterize the rate-determining step. The pKa values of the nucleophiles ranged between -1.74 and 15.74, and for the nucleofuges, they were in the range of 10.50-0.92. For nucleophiles with pKa values up to about 10, βlg was 0.10-0.15, and βnu changed from 0.48 to 0.35 for the strongest electron-withdrawing nucleofuge. It was concluded that the water-catalyzed hydrolyses, and also aminolyses with moderately basic amines, occur with rate-determining formation of the tetrahedral intermediate. For strong bases such as hydroxide ion, the disappearance of the intermediate becomes the slowest step. The reaction of cellulose xanthic esters with external nucleophiles as hydroxide ion and amines shows simple first-order kinetics and is slower than alkyl or sugar xanthates, probably due to the diffusion effect through the tight cybotactic region of cellulose.
Correlation of the rates of solvolysis of phenyl chlorothionoformate and phenyl chlorodithioformate
Kevill, Dennis N.,D'Souza, Malcolm J.
, p. 1118 - 1122 (2007/10/03)
The specific rates of solvolysis of phenyl chlorothionoformate (PhOCSCl) are remarkably similar to those previously reported for phenyl chlorothioformate (PhSCOCl). When analyzed using the extended Grunwald-Winstein equation over the usual range of solvent types, these solvolyses show essentially identical divisions into the solvents favoring the addition-elimination channel and those favoring the ionization channel. The introduction of one sulfur caused a partial shift away from the addition-elimination pathway, which was dominant over the full range of solvents for phenyl chloroformate (PhOCOCl). Consistent with these results, introduction of the second sulfur within phenyl chlorodithioformate (PhSCSCl) leads to a completion of this shift, such that an extended Grunwald-Winstein treatment of the specific rates of solvolysis now shows the ionization pathway to be dominant over the full range of solvents.
Reactions of Aromatic Diazonium Salts with Butyl Vinyl Ether in the Presence of Potassium O-Alkyl Dithiocarbonates
Grishchuk,Kudrik,Gorbovoi,Ganushchak
, p. 1482 - 1485 (2007/10/03)
Arenediazonium tetrafluoroborates, sulfates, and nitrates react with butyl vinyl ether in aqueous acetone in the presence of potassium O-alkyl dithiocarbonates to yield O-alkyl S-(2-aryl-1-butoxyethyl) dithiocarbonates (Alk = Et, Bu, t-Bu). The reaction is accompanied by formation of O-alkyl S-aryl dithiocarbonates, which are the main products of the reaction of arenediazonium salts with potassium O-alkyl dithiocarbonates in the absence of unsaturated compound.
Reactions of Aromatic Diazonium Salts with Esters of Acrylic and Metacrylic Acids in the Presence of Potassium Xanthates
Grishchuk,Gorbovoi,Kudrik,Ganushchak
, p. 619 - 622 (2007/10/03)
Alkyl 2-(alkoxycarbothioylthio)-3-arylpropanoates have been prepared by the reactions of aryldiazonium tetrafluoroborates, sulfates, and nitrates with esters of acrylic and metacrylic acids in acetone and aqueous acetone media in the presence of potassium
