| Abstrakt: |
Sodium complexes 3 and 5 of the spin labeled monoazacrown ethers 2,2,15,15-tetramethyl-1-aza- 4,7,10,13-tetraoxacyclopentadecane-1-oxyl (2) and 1,4,7,10-tetraoxa-13-(2′,2′,6′,6′-tetramethyl-piperidine-1′-oxyl-4′-yl)azacyclopentadecane (4) were synthesized and studied by EPR and ENDOR spectroscopies. The hyperfine splitting parameter and the g value of the complex 5, containing the exocyclic nitroxyl moiety, were identical to the parent complexon 4, i.e., aN= 15.6 G. g = 2.0060 ± 0.0001. In contrast, the data for the complex 3, containing the endocyclic nitroxyl moiety were different. Thus, the spectrum of the complex 3 was a triplet of quartets with aN= 15.7 G. aNa= 2.47 G, g = 2.0062 ± 0.0001, whereas the spectrum of the parent complexon 2 was a triplet with aN= 15.5 G, g = 2.0059 ± 0.0001. |
