Picture of smart phone in human hand

World leading smartphone and mobile technology research at Strathclyde...

The Strathprints institutional repository is a digital archive of University of Strathclyde's Open Access research outputs. Strathprints provides access to thousands of Open Access research papers by University of Strathclyde researchers, including by Strathclyde researchers from the Department of Computer & Information Sciences involved in researching exciting new applications for mobile and smartphone technology. But the transformative application of mobile technologies is also the focus of research within disciplines as diverse as Electronic & Electrical Engineering, Marketing, Human Resource Management and Biomedical Enginering, among others.

Explore Strathclyde's Open Access research on smartphone technology now...

A single aqueous reference equilibrium constant for amide synthesis-hydrolysis

Ulijn, R.V. and Moore, B.D. and Janssen, A.E.M. and Halling, P.J. (2002) A single aqueous reference equilibrium constant for amide synthesis-hydrolysis. Journal of the Chemical Society, Perkin Transactions 2, 2002 (5). pp. 1024-1028. ISSN 1472-779X

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

Experimentally measured equilibrium constants at a given pH in part reflect the contributions of ionisation of acidic and basic groups present. These contributions can be isolated from the equilibrium constant by expressing all reactant concentrations in terms of the uncharged forms only. This article presents methods to calculate uncharged reference equilibrium constants for amide synthesis/hydrolysis reactions. For zwitterions in particular these methods are not always straightforward. It is explained how (microscopic) pK(a) values can be estimated where experimental values are not available. A large number of equilibrium data are analysed for hydrolysis or synthesis of protected and unprotected di- and tri-peptides, beta-lactam antibiotics, and acyl acids and amides. This reveals just how similar the reference equilibrium constants are when ionisation is properly accounted for (K-ref(0) = 10(3.6) M-1) regardless of the molecular form of the reactants involved.