4-thiazine

2052's picture

Kinetics and Mechanism of Osmium(VIII)-Catalyzed Oxidation of Thiomorpholine by Alkaline Hexacyanoferrate(III)

Journal Title, Volume, Page: 
Journal of Applied Sciences, 2002, Volume: 2, Issue: 7, Page No.: 742-746, DOI: 10.3923/jas.2002.742.746
Year of Publication: 
2002
Authors: 
Mohammed M. Al Subu
Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, An-Najah National University, Nablus, Palestine
Current Affiliation: 
Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, An-Najah National University, Nablus, Palestine
Preferred Abstract (Original): 

Thiomorpholine (tetrahydro-1,4-thiazine), in the presence of Os(VIII) as catalyst, is oxidized by alkaline hexacyanoferrate(III) to 2-hydroxythiomorpholine. There is a first-order dependence in [Fe(CN)63-] and [Os(VIII)] and zero-order dependence in [thiomorpholine] and [OH-]. The observed rate constant was dependent on [Fe(CN)64-] the type of electrolyte and the permitivitty of the reaction medium (10-40% ethanol). The proposed mechanism includes the formation of a transient [OsO4(OH)2 ]2--thiomorpholine complex prior to the rate-determining regeneration of OsVIII by [Fe(CN)63-]. The values of the enthalpy and entropy of activation are calculated from rate constant values measured at different temperatures (20-40 ° C).

Syndicate content