623-79-0Relevant articles and documents
Dithiocarbonato nickel, palladium and platinum complexes bearing bis(diphenylphosphino)ferrocene: synthesis and X-ray structure determination
El-Khateeb, Mohammad,Tanash, Qusay,Abul-Futouh, Hassan,G?rls, Helmar,Weigand, Wolfgang
, (2019)
Abstract: The dithiocarbonato metal complexes M(κ2S,S-S2CO)(κ2P,P-dppf) {M= Ni, Pd, Pt; dppf= bis(diphenylphosphino)ferrocene} are obtained from the reaction of the metal(II) complexes [M(κ2S,S-S2COEt)2] with the dppf ligand or from the chloride substitution of M(κ2P,P-dppf)Cl2 by the O-ethyldithiocabonato anion. These complexes are produced by C-O bond cleavage by the O-ethyldithiocarbonato anion present in solution. These new complexes have been characterized by UV-Vis, NMR, IR spectroscopy and elemental analysis. The structures of the three complexes were further confirmed by single-crystal X-ray diffraction analysis. Graphical Abstract: The dithiocarbonato metal complexes M(κ2S,S-S2CO)(κ2P,P-dppf) {M= Ni, Pd, Pt, dppf= bis(diphenylphosphino)ferrocene} are obtained from the reaction of the metal(II) complexes [M(κ2S,S-S2COEt)2] with the dppf ligand or from the chloride substitution of M(κ2P,P-dppf)Cl2 by the O-ethyldithiocabonato anion. These new complexes have been characterized by UV-Vis, NMR, IR spectroscopy and elemental analysis. The structures of complexes 1–3 were further confirmed by single-crystal X-ray diffraction analysis.[Figure not available: see fulltext.].
Reihlen,Elben,Everet
, p. 45,50 (1931)
Supramolecular interactions in sodium N-(ethoxythioxomethyl)-β- alaninate-water (4/6) crystal and its application in synthesis of L-carnosine
Zhang, Shi-Jie,Xu, Feng,Yang, Wei-Ji,Hu, Wei-Xiao
, p. 1182 - 1189 (2013/02/22)
Compound sodium N-(ethoxythioxomethyl)-β-alaninate (sodium 3-(ethoxycarbonothioyl)propanoate) was synthesized and characterized by IR, 1HNMR, ESI-HRMS and single crystalX-ray diffraction. Single crystalX-ray diffraction analysis showed that the title compound crystallized in the triclinic space group P-1 with cell parameters a = 10.142 (2) A, b = 13.738 (3) A, c = 15.751 (3) A, α= 72.937 (2)°, β = 78.694 (2)°, γ = 89.999 (2)°, V = 2053.4 (7) A3, Dc = 1.464 g cm-3, Z = 2. In the extended structure of sodium N-(ethoxythioxomethyl)-β-alaninate-water (4/6), (NaL)4· 6H2O [L = CH3CH2OC(S)NHCH2CH 2COO], ligands (Ls) are stabilized by intermolecular O-H···O, N-H···O, C- H···O and weak O-H···S and C-H···S linkages, which further consolidate the crystal packing, making the ligand chains stacked along [0-1 1], and intramolecular O-H···S hydrogen bond is also observed. Each Na atom is surrounded with six O atoms, forming an octahedron and mutually bonded as tetramers. These tetramers are linked through O atom bridges from water molecules, extending as layers in the ab plane. In addition, synthesis of β-alanyl dipeptides was developed with particular focus on the preparation of L-carnosine. Springer Science+Business Media New York 2012.
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.