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1H and 13C NMR study of paramagnetic chiral macrocyclic lanthanide complexes

✍ Scribed by Jerzy Lisowski

Publisher
John Wiley and Sons
Year
1999
Tongue
English
Weight
129 KB
Volume
37
Category
Article
ISSN
0749-1581

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✦ Synopsis

The chiral macrocyclic complexes obtained in a template condensation of (R,R)-1,2-diaminocyclohexane and 2,6-diformylpyridine, Ln \ La(III), Ce(III), Eu(III) and Yb(III), were studied by 1H [LnL](NO 3 ) 3 , and 13C NMR spectroscopy. The signal assignment was based on COSY, NOESY and HMQC measurements and the isotropic shifts of the paramagnetic complexes were analysed. The spectra of the investigated compounds in methanolÈchloroform solution indicate a helical conformation of the ligand. The chiral D 2 -symmetrical, complexes are able to form diastereoisomeric adducts with D-and L-aminoacids that can be distin-[LnL](NO 3 ) 3 guished by 1H NMR spectroscopy.

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