Tris(ethanol-O)tris-(picrato-κ² O ¹,O ²)lanthanum(III) tri-2-pyridylamine solvate

The title compound, [La(C6H2N3O7)3(C2H6O)3]·C15H12N4, has two mol-ecular building blocks, namely the neutral mononuclear adduct of lanthanum picrate with ethanol [i.e. La(pic)3:EtOH (1:3); La(pic)3 = lanthanum picrate and EtOH = ethanol] and the oligodentate aromatic nitro-gen base tri-2-pyridylamine (tpa). The asymmetric unit contains two formula units. The compound was prepared during an investigation of the stereochemistry of lanthanoid picrate complexes with O-donor ligands. The metal-ligand adduct adopts a nine-coordinate tricapped trigonal-prismatic metal atom environment. The stereochemical arrangement of the ligands about the metal core is typical of a fac-isomer with stoichiometry M(bidentate)3(monodentate)3. Face-to-face hydrogen bonds are found between the tpa mol-ecule and the ethanol ligands. One ethanol ligand is disordered over two positions, with site occupancy factors of ca 0.7 and 0.3. The oxygen atoms of a nitro group are also disordered over two positions; the site occupancy factors are ca 0.6 and 0.4.