J-edited pure shift NMR for the facile measurement of (n)J(HH) for specific protons.

Chemphyschem

NMR Research Centre and Solid State Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012 (India), Fax: (+81) 8023601550.

Published: April 2015

We report a novel 1D J-edited pure shift NMR experiment (J-PSHIFT) that was constructed from a pseudo 2D experiment for the direct measurement of proton-proton scalar couplings. The experiment gives homonuclear broad-band (1)H-decoupled (1)H NMR spectra, which provide a single peak for chemically distinct protons, and only retain the homonuclear-scalar-coupled doublet pattern at the chemical-shift positions of the protons in the coupled network of a specific proton. This permits the direct and unambiguous measurement of the magnitudes of the couplings. The incorporation of a 1D selective correlation spectroscopy (COSY)/ total correlation spectroscopy (TOCSY) block in lieu of the initial selective pulse, results in the exclusive detection of the correlated spectrum of a specific proton.

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http://dx.doi.org/10.1002/cphc.201402792DOI Listing

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