4490-97-5Relevant articles and documents
Selective N-acetylation with concurrent S-oxidation of o-amino thiol at ambient conditions over Ce doped ZnO composite nanocrystallites
Jagtap, Rohidas,Sakate, Sachin,Pardeshi, Satish
, p. 19 - 28 (2018/04/27)
The oxidative S–S coupling of thiol to disulfide is an imperative chemical transformation in the domain of biological processes and also finds numerous chemical applications. The CeO2 and ZnO are significant catalysts for oxidation of thiol to disulfide and N-acetylation of amines respectively. Dithiobis(phenylene)bis(benzyldeneimine) moiety containing N-acetyl and disulfide functional groups is a potential antimicrobial agent with Leishmanicidal and antihyperlipidemic activities. Herein, we report a synchronized catalytic application of Ce doped ZnO (Ce-ZnO) and CeO2-Ce-ZnO composites for selective synthesis of Dithiobis(phenylene)bis(benzyldeneimine) from o-amino thiol. The Ce-ZnO samples were synthesized by simple co precipitation method by calcination of hydroxide precursors at 400 °C to get 0–10% Ce-ZnO nanocrystallites. The formation of CeO2-Ce-ZnO composite material was observed beyond 1.5% Ce concentration. The synthesized materials were well characterized by IR, XRD, DRS spectroscopy and SEM-EDS analysis. The application of Ce doped ZnO as an efficient catalyst towards the selective N-acetylation and concurrent S-oxidation of o-amino thiol to afford Dithiobis(phenylene)bis(benzyldeneimine) at ambient temperature in acetonitrile was deliberated. Among all screened catalysts, the maximum selectivity was found for 7.5% Ce-ZnO as CeO2-Ce-ZnO composite catalyst. Lewis acidic property of catalyst supported probable mechanism for achieved dual transformations. Also, the 7.5% Ce-ZnO catalyst has demonstrated a versatile S–S coupling ability for variety of thiol substrates with excellent stability.
Design, syntheses, and characterization of dioxo-molybdenum(vi) complexes with thiolate ligands: Effects of intraligand NH...S hydrogen bonding
Sengar, Raghvendra S.,Miller, Jonathan J.,Basu, Partha
, p. 2569 - 2577 (2008/09/20)
Presence of the hydrogen bonding near a metal center can influence the properties of the complex. Here, we describe changes in redox and spectral properties in discrete dioxo-molybdenum centers coordinated by a single thiolato ligand that can support an intra-ligand hydrogen bond. We have utilized thiophenolato ligands that can harbor hydrogen bonding between the thiophenolato sulfur with an amide functionality creating either a five- or a six-membered ring. Methylation of the amide functionality removes the NH...S hydrogen bonding thus providing a basis for understanding the effect of hydrogen bonding. These thiophenolato ligands have been used in synthesizing dioxo-MoVI complexes of type Tp*MoO2(S-o-RC6H4), where R = CONHMe (11), CONMe2 (12), NHCOMe (13), and N(Me)COMe (14). The complexes have been characterized by NMR, infrared, and UV-visible spectroscopy. Spectroscopic data clearly indicate the presence of hydrogen bonding in both 11 and 13, and stronger in 13, where hydrogen bonding stabilizes a five-membered ring. All complexes exhibit a MoVI/MoV redox couple and redox potentials are modulated by the nature of H-bonding. Compound 14 with the electron-releasing N(Me)COMe group has the highest reduction potential and is more difficult to reduce. The Royal Society of Chemistry.
Thermal ring transformation of 2,2-disubstituted benzothiazoline 1- oxides
Shimizu,Kanematsu,Hashimoto,Kobayashi
, p. 73 - 79 (2007/10/03)
Thermal rearrangement of 2,2-disubstituted benzothiazoline 1-oxides (1) in aprotic solvent afforded the corresponding 1,4-benzothiazines (2) and (3). The thermal reaction performed in the presence of electron-deficient acetylenic compounds produced new tricyclic compounds (7) whose structures have been established by an X-Ray crystal structure determination.
