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NMR investigation into the dynamic behaviour of a novel C2-symmetric macrocyclic ligand. | LitMetric
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NMR investigation into the dynamic behaviour of a novel C2-symmetric macrocyclic ligand.

J Erik W Scheuermann Edson S Bento Geoffrey E Hawkes Michael Watkinson

Magn Reson Chem

Department of Chemistry, Queen Mary, University of London, Mile End Road, London E1 4NS, UK.

Published: April 2005

The variable-temperature (1)H NMR spectra of a tosylated triazacyclononane are reported. The spectra show a dynamic process which is assigned to hindered rotation about the amide-like N--S bonds, and a value for the free energy of activation for the rotations is derived, DeltaG* = 50.2 kJ mol(-1) at 273 K. Steric and electronic factors which influence the barrier are discussed.

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http://dx.doi.org/10.1002/mrc.1539DOI Listing

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