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The stereochemistry of crown ethers. III—Conformational variations during alkali complexation

✍ Scribed by E. Kleinpeter; S. Stoss; M. Gäbler; W. Schroth

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

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✦ Synopsis

The 'H and "C NMR spectra of a series of structurally related crown ethers were recorded, and alkali metal complexation of the crown ethers was studied for different Li, Na and K salts. The alkali metal salt-induced 'H and "C chemical shifts are discussed in terms of conformational changes within the macrocyclic ring, and the results obtained were proved to be general by means of NOE enhancement factors and spin-lattice relaxation time measurements. KEY WORDS 'H/I3C NMR Crown ethers Complexation with alkali metal cations Intramolecular flexibility

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