Wydział Chemii

Marta Paluch

Katarzyna Ślepokura

Tadeusz Lis

Jerzy Lisowski

2011

Inorganic Chemistry Communications

14

92-95

10.1016/j.inoche.2010.09.039

Naukowa

Angielski

Artykuł

The large trioxahexaaza chiral macrocyclic amine L binds three lanthanide(III) ions (Sm(III), Eu(III) and Tm(III)) in such a way that the Ln(III) ions are bridged by the phenolate oxygen atoms of the macrocycle and additional hydroxo bridges. The formation of symmetrical trinuclear complexes is confirmed by ¹H NMR, ESI-MS and elemental analyses. X-ray crystal data for the Eu(III) complex reveal the presence of the Ln₃(μ₃-OH)₂ cluster in the centre of the macrocycle. On the other hand, the larger La(III) or Pr(III) lanthanide ions form dinuclear complexes with the macrocycle L under similar conditions. The titration of the macrocycle L with europium(III) nitrate and sodium hydroxide solutions indicates formation of mononuclear and trinuclear species, while no substantial amount of dinuclear complexes are observed. The formation of the Ln₃(μ₃-OH)₂ core in the trinuclear complexes is cooperative, i.e. the binding of the third Ln(III) ion by the macrocycle L is stronger than the binding of the second Ln(III) ion.

lanthanides, macrocycles, Trinuclear complexes, Chiral complexes, Cooperativity, X-ray crystal structures

https://doi.org/10.1016/j.inoche.2010.09.039

http://www.elsevier.com