Measurement of coupling constants in symmetrical spin systems using a full multiple‐step cross‐polarization‐driven NMR pulse scheme

AbstractNew NMR pulse schemes completely driven under homonuclear and heteronuclear cross‐polarization conditions are proposed for the study and the measurement of coupling constants in symmetrical molecules in solution. The appropriate superimposition of independent magnetization components can afford several spin‐selective multiplet patterns that are suitable for the determination of the magnitude and the sign of proton–proton and proton–carbon coupling constants with optimum sensitivity levels. A detailed product operator formalism analysis for the proposed doubly selective 1D and nonselective 2D HCP‐TOCSY versions is provided and experimental verification for the configurational analysis of symmetric olefinic systems having chemical equivalence is demonstrated. Copyright © 2005 John Wiley & Sons, Ltd.