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Measurement of long-range proton—carbon coupling constants in medium-sized molecules

✍ Scribed by Miloš Hricovíni; Tibor Liptaj

Publisher
John Wiley and Sons
Year
1989
Tongue
English
Weight
295 KB
Volume
27
Category
Article
ISSN
0749-1581

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✦ Synopsis

A m d i e d version of the two-dimensional semiselective INEPT experiment is presented which allows the determination of long-range protowarbon couplings in medium-sized molecules. The difference in the TI relaxation times is utilized for the reduction of the number of protons from which coherence is transferred. This results in a simpliication of the 1D and 2D spectra obtained. The capability of the proposed pulse sequence is demonstrated by the determination of the long-range couplings in a model molecule. KEY WORDS Long-range proton-carbon couplings Partially relaxed overlapping multiplets Semiselective coherence transfer A is usually set to a shorter value than the optimum for the cancellation of the antiphase component 2S, Tz.

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