A Definitive NMR Solution for a Simple and Accurate Measurement of the Magnitude and the Sign of Small Heteronuclear Coupling Constants on Protonated and Non‐Protonated Carbon Atoms

Simply successful: a proton-selective HSQMBC-TOCSY experiment can be used to measure small proton-carbon ((n)J(CH); n>1) coupling constants on both protonated and non-protonated carbon atoms. The method combines in a single pulse scheme all the benefits of the widely used HSQMBC and HSQC-TOCSY experiments. The magnitude and the sign of (n)J(CH) can be determined simply with excellent accuracy.