Lanthanide(III) complexes of six-nitrogen-donor macrocyclic ligands with benzyl-type peripheral substituents, and crystal structure of [La(NO3)2(H2O)(C36H38N6)].(NO3)(H2O)

Lanthanide(III) complexes of six-nitrogen-donor macrocyclic ligands carrying a benzyl-type group, -CH2-C6H4-X (X = -H, -OH, or -NH2), at each di-imine side-chain were synthesized by the Schiff-base condensation of 2,6-diacetylpyridine with substituted S- and R,S-1,2-diaminopropanes. The complexes were obtained as mixtures of constitutional isomers and stereoisomers, which were identified by 1H NMR spectra and separated by fractional crystallization. The molecular structure of the 11-coordinate complex [La(NO3)2(H2O)(C36H38N6)](NO3)(H2O) was established by X-ray crystallography.