Crystal structure of (5-bromo-2,3-diaminopyridine-N,N′-bis(3-methoxysalicylideneiminato)- O,O′,N,N′)nickel(II) – methanol (1:1), Ni(C21H16BrN3O4) · CH3OH

Abstract

Source of materialThe Schiff base ligand was synthesized by condensation 5-bromo-2,3-diaminopyridine and 2-hydroxy-3-methoxybenzaldehyde with the ratio 1:2inethanol. The synthesis of the title complex was carried out by reacting Ni(ClO 4 ) 2 · 6H 2 Oand the schiff base ligand (1:1, molar ratio) in methanol. After stirring, the process was continued for about 30 min at room temperature. The mixture was filtered and the filtrate was allowed to partially evaporate in air for sevral days to produce red-brown crystals suitable for X-ray diffraction with ayield about 60 %. DiscussionSchiff-bases have played an important role in the development of coordination chemistry as they readily form stable complexes with most of the transition metals, in which some could exhibit interesting properties [1][2][3][4].The coordination sphere for the Ni(II) ion in the title crystal structure is aslightly distorted square planar, in which the four positions are occupied by two Natoms and two Oatoms of the Schiffbase ligand. The mean deviation from the plane formed by the two Natoms, two Oatoms and the Ni ion is only 0.035 Å,indicative of that these five atoms can form aperfect plane. The bond lengths of Ni-Na re 1.874(3) Å and 1.929(3) Å,a nd Ni-O 1.861(2) Å and 1.905(2) Å,respectively, are consistant with the corresponding distances in 6,6'-dimethoxy-2,2'-(ethane-1,2-diyl-bis(nitrilomethylidyne)diphenolato)nickel(II) [5].