Unusual intermolecular "through-space" j couplings in p-se heterocycles
Paula Sanz Camacho1, Kasun S Athukorala Arachchige1, Alexandra M Z Slawin1
1†School of Chemistry, EaStCHEM and Centre of Magnetic Resonance, University of St. Andrews, Fife, KY16 9ST, U.K.
Abstract:
Solid-state NMR spectra of new P-Se heterocycles based on peri-substituted naphthalene motifs show the presence of unusual J couplings between Se and P. These couplings are between atoms in adjacent molecules and occur "through space", rather than through conventional covalent bonds. Experimental measurements are supported by relativistic DFT calculations, which confirm the presence of couplings between nonbonded atoms, and provide information on the pathway of the interaction. This observation improves the understanding of J couplings and offers insight into the factors that affect crystal packing in solids, for future synthetic exploitation.
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