NMR studies of mixed-ligand lanthanide complexes in solution: Pseudorotation and ring inversion of 18-crown-6 molecule in cerium subgroup chelates

Sergey P. Babailov, Lubov D. Nikulina

Результат исследования: Материалы для журналаСтатья

8 Цитирования (Scopus)

Аннотация

1H and 13C NMR measurements are reported for the CDCl3 and CD2Cl2 solutions of [La(NO 3)3(18-crown-6)] (I), [Pr(NO3) 3(18-crown-6)] (II) and [Ce(NO3)3(18-crown-6)] (III) complexes. Temperature dependencies of the 1H NMR spectra of II have been analyzed using the dynamic NMR methods for multi-site exchange. Two types of conformational dynamic processes in II were identified (the first one with activation enthalpy ΔH=26 ± 4 kJ/mol is conditioned by interconversion of complex enantiomeric form and pseudorotation of macrocycle molecule upon the C2 symmetry axis, the second one with ΔH=46 ± 5 kJ/mol is conditioned by macrocycle molecule inversion). Studies of the values of the lanthanide-induced shifts revealed that the structure of complexes in solution is similar to that reported for the complex I in the crystal state.

Язык оригиналаАнглийский
Страницы (с... по...)103-109
Количество страниц7
ЖурналJournal of Inclusion Phenomena and Macrocyclic Chemistry
Том51
Номер выпуска1
DOI
Статус публикацииОпубликовано - фев 2005
Опубликовано для внешнего пользованияДа

    Fingerprint

ASJC Scopus subject areas

  • Chemistry(all)
  • Condensed Matter Physics

Цитировать