Accurate measurement of long range proton–carbon scalar coupling constants

Abstract

The accuracy and practicality of measuring heteronuclear scalar coupling constants, ⁿJ_CH, from modern NMR experimental methods is examined, based on F1 or F2 evolution of ⁿJ_CH in HSQMBC (including EXSIDE) and HMBC experiments. The results from these methods are compared to both robust experimental data (derived from coupled ¹³C spectra), computed (Density Functional Theory) and literature values where available. We report on the accuracy, ease of use and time efficiency of these multi-dimensional methods and highlight their extent and limitations.