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HMBC-like experiment based on longitudinal csa/dipolar cross-correlation.

Sabine Bouguet-Bonnet·Sébastien Leclerc·Pierre Mutzenhardt·Daniel Canet
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Abstract

A gradient-based sequence is proposed for efficiently filtering out all quantities except the longitudinal two-spin order, created by csa/dipolar cross-correlation rates. The dipolar interaction is between a proton and a heteronucleus, the csa being generally the one of the heteronucleus. Proton detection is carried out to benefit from maximum sensitivity. The resulting two-dimensional spectrum has the same aspect as an HMBC spectrum, implying the existence of a J coupling between the two considered nuclei, but here cross-peaks indicate the strength of the relevant csa/dipolar cross-correlation rate. The method is especially interesting in the case of medium-sized molecules where a given heteronucleus is subjected to several csa/dipolar cross-correlation effects, along with the corresponding J couplings.

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Carbon IsotopesMacromolecular SubstancesNuclear Magnetic Resonance, BiomolecularProtonsSensitivity and SpecificityJournal Article

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Sabine Bouguet-Bonnet, Sébastien Leclerc, Pierre Mutzenhardt, Daniel Canet. 2005. HMBC-like experiment based on longitudinal csa/dipolar cross-correlation.. https://doi.org/10.1016/j.jmr.2004.11.012

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