Crystal structures of the complexes of rare earth picrates with N, N, N′, N′-tetraphenyl-3, 6-dioxaoctanediamide

Abstract

The complexes of rare earth picrate with N, N, N′, N′-tetraphenyl-3, 6-dioxaoctanediamide (TDD), [Eu(pic)3(TDD)]-2CH3CN and [Y(pic)3(TDD)], have been synthesized. The crystal structures reveal that TDD acts as a tetradentate ligand, forming a ring-like coordination structure with its oxygen atoms together with one oxygen atom of the bidentate picrate. In the Eu (III) complex, the europium ion with a larger ionic radius lies out of the ring, while in the Y (III) complex, the yttrium ion with a smaller ionic radius enters the cavity of the ligand. The structures of the complexes are greatly affected by the ionic radii due to participation of the picrates in coordination.