Rate Coefficients by Integration of Total Reaction NMR Spectra.

Reaction kinetics provide quantitative descriptions of phenomenological behavior that can be correlated with underlying chemical reaction mechanisms. Kinetic data is conventionally interrogated using one of three general methods: linear or nonlinear regression, numerical parameter estimation, and modern graphical analysis. Cumulative temporal concentrations (CTCs) derived from areas under temporal concentration curves are an alternative method to estimate kinetic parameters from reaction monitoring data. The requisite areas under temporal concentration curves are conveniently estimated from a total reaction NMR spectrum (TRS) generated using routine NMR spectroscopic acquisition and processing methods. Six case studies, involving intermediates, equilibria, catalysis, branching, and bimolecular processes, demonstrate how a combined TRS/CTC approach offers a straightforward method to estimate efflux rate coefficients for isolated chemical steps, without curve fitting.