Spectroscopic and crystal structure of europium(III) picrate complexes with novel BINOL derivatives

Two novel ligands N-Benzyl-2-{2'-[(benzyl-phenyl-carbamoyl)-methoxy]-[1,1']binaphthalenyl-2-yloxy}-N-phenyl-acetamide (L1) and N-Methyl-2-{2'-[(methyl-phenyl-carbamoyl)-methoxy]-[1,1']binaphthalenyl-2-yloxy}-N-phenyl-acetamide (L2), and their europium(III) complexes with picrate, [Eu(pic)(3)(L1)] and [Eu(pic)(3)(L-2)], were synthesized and characterized by elemental analysis, IR, UV-Vis and fluorescence spectroscopy. The crystal structure of [Eu(pic)(3)(L1)]center dot 2CHCl(3) was determined by single crystal X-ray diffraction. The europium atom is coordinated by nine oxygen atoms of four from the L1 and five from two bidentate and one unidentate picrates. The fluorescent intensity of [Eu(pic)(3)(L2)] is about 2.6 times that of [Eu(pic)(3)(L1)] in solid states. But in CHCl3 solution, the fluorescent intensity of [Eu(pic)(3)(L1)] is stronger slightly than [Eu(pic)(3)(L2)].