Stereochemistry of Crown Ethers I. Conformational and Dynamic Behaviour of N-Tosyl-Substituted Diaza Crown Ethers

Article abstract of DOI:10.1002/mrc.1260260507

The variable temperature 1H and 13C NMR spectra of some N-tosyl diaza crown ethers have been obtained.They are discussed with respect to the preferred conformers of the crowns and the free energies of activation of the interconversional process of the large ring.Both the preferred conformers and the ring interconversional barriers have been found strongly dependent on the structure and the ring size of the studied compounds.KEY WORDS Variable-temperature 1H and 13C NMR spectra N-tosyl diaza crown ethers Crown conformation Free energies of activation.