Crystal Structure of N,N'-Bis(3,4,5-trimethoxybenzylidene)-ethylenediaminediiodozinc(II)

Abstract

Schiff-base ligands have been extensively studied in the development of coordination complexes of transition metals. Depending on the ligands involved, Zn(II) complexes show a wide variety of structures, such as dinuclear triple helix and polymer complexes. 5,6 The Schiff-base ligand (3,4,5-MeO-ba)2en acts as a bidentate ligand coordinating via two N atoms to the metal center.2 As part of our continuing interest in the synthesis of transition metal complexes with Schiff base ligands, 1,2 we have reported the title complex, [Zn((3,4,To a stirring solution of 320 mg (1 mmol) of ZnI2 in 3 ml of methanol was added dropwise a solution of 416 mg (1 mmol) of (3,4,5-MeO-ba)2en 7 in 3 ml of dichloromrthane. The solution was stirred for an additional 30 min at room temperature. The product precipitated as a white powder, and was collected by filtration and then dissolved in 20 ml of acetone and filtered. The filtrate was left overnight to give colorless crystals.A colorless single crystal with dimensions of 0.25 ¥ 0.20 ¥ 0.18 mm 3 was chosen for a single-crystal X-ray diffraction study.Data were collected on a Enraf-Nonius CAD-4 diffractometer (graphite Mo Ka radiation, 071073 Å) at 293K. Details of the data collection and refinement parameters are listed in Table 1. The structure was solved by direct methods.The positions of the H atoms were placed in at geometrically idealized positions (C-H = 0.93 Å, N-H = 0.86 Å) and constrained to ride on their parent atoms with Uiso(H) = 1.2Ueq(carrier atom).Selected interatomic distances are gathered in Table 2.The crystal structure of the title complex, [Zn((3,4, The title complex, [Zn((3,4,5-MeO-ba)2en)I2], has been synthesized and structurally characterized by single crystal X-ray diffraction. The geometry around the zinc atom is a distorted tetrahedron. This structure consists of intermolecular hydrogen bonds of the type C-H·I and C-H·O.