Abstract
Multiplet structure deconvolution provides a robust method to determine the values of the coupling constants in first-order 1D nuclear magnetic resonance (NMR) spectra. Functions simplifying the coupling structure for partners with spin larger than and for doublets with unequal amplitudes were introduced. The chemical shifts of the coupling partners causing mild second-order effects can, in favourable cases, be calculated from the slopes measured in doublet structures. Illustrations demonstrate that deconvolution can straightforwardly analyse multiplet posing difficulties to humans and, in some cases, extract coupling constants from unresolved multiplets.
Highlights
When studying organic compounds, 1D 1H nuclear magnetic resonance (NMR) spectra are often the only, and sufficient, analytical method engaged
We shall demonstrate the power of the application of multiplet deconvolution outside the world of 2D correlation spectroscopy, where positive and negative peaks coexist and cause specific challenges (Jeannerat and Bodenhausen, 1999), and apply it to the common – not to say mundane – multiplet structure present in standard 1D NMR spectra
This paper presents a follow-up of one published in 1999 (Jeannerat and Bodenhausen, 1999) which showed how to effectively use a set of inverse functions of F to obtain, through a recursive procedure (Novicand Bodenhausen, 2002), the list of the coupling constants and the line shape G
Summary
1D 1H nuclear magnetic resonance (NMR) spectra are often the only, and sufficient, analytical method engaged. The presence of a methyl group on a carbon bearing a proton will produce a quartet structure, the conformation of a double bond has clearly distinct geminal coupling constants, dihedral angle influences vicinal coupling constants (Karplus, 1963), etc These NMR parameters are helping researchers to identify their products, but they allow reviewers to assess the validity of the argument supporting their identification and benefit the community by providing very precious information when structurally similar compounds are encountered. Mestrelab’s Mnova software (Mnova NMR version 14.3.0, 2021) This method was originally developed during the 90s to automatize the analysis of multiplet structure from spectra generated by one of the forgotten pulse sequences: the soft-COSY experiment (Emsley et al, 1990). We shall demonstrate the power of the application of multiplet deconvolution outside the world of 2D correlation spectroscopy, where positive and negative peaks coexist and cause specific challenges (Jeannerat and Bodenhausen, 1999), and apply it to the common – not to say mundane – multiplet structure present in standard 1D NMR spectra
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
