The thiocarbonyl ‘S’ is softer than thiolate ‘S’: A catalyst-free one-pot synthesis of isothiocyanates in water

Jamir, Latonglila ; Ali, Abdur Rezzak ; Ghosh, Harisadhan ; Chipem, Francis A. S. ; Patel, Bhisma K. (2010) The thiocarbonyl ‘S’ is softer than thiolate ‘S’: A catalyst-free one-pot synthesis of isothiocyanates in water Organic & Biomolecular Chemistry, 8 (7). pp. 1674-1678. ISSN 1477-0520

Full text not available from this repository.

Official URL: http://pubs.rsc.org/en/content/articlelanding/2010...

Related URL: http://dx.doi.org/10.1039/B923336A

Abstract

Treatment of the preformed or the in situ generated aryl/alkyl dithiocarbamates triethylammonium salt (ArNHCSS.Et3NH+) with methyl acrylate in an aqueous medium gave solely arylisothiocyanate (ArNCS), whereas the in situ generated aryl dithiocarbamic acid (ArNHCSS.H+) yielded exclusively the thia-Michael adduct (ArNHCSSCH2CH2COOMe). This differential reactivity can be explained by two alternative mechanisms which is dependent both on the nature of the counter cationand on the pH of the reaction medium. Irrespective of the counter cations, the thiocarbonyl sulfur (=S) atom, having large orbital-coefficient, is softer compared to the thiol/thiolate sulfur (-SH/S) in a dithiocarbamate salt and the former adds to the Michael acceptor by a 1,4-addition.

Item Type:Article
Source:Copyright of this article belongs to Royal Society of Chemistry.
ID Code:113929
Deposited On:30 Apr 2018 12:29
Last Modified:30 Apr 2018 12:29

Repository Staff Only: item control page