engleski

Monoaquabis(pyridine)bis(saccharinato)copper(II), [Cu(H2O)(py)2(sac)2]

The systematic structural and spectroscopic study of pyridine saccharinato complexes with various metals (Mn, Co, Ni, Cu, Hg, Pb) is a part of our broader research on the metal saccharinate complexes with different mono- (imidazole, pyridine) or polymembered ring bases (2,2'-bipyridine, o-phenantroline) coordinated to the metal atom. Recently we have determined the crystal structure of pyridine saccharinato complexes of ClHg(II), Co(II) and Ni(II). Here, the results of the crystal structure determination of the Cu(II) pyridine saccharinate monohydrate are briefly reported. Crystal data. C24H20CuN4O7S2, Orthorhombic, I ba2, Mr = 604.10, a = 9.487(7), b = 21.545(1), c = 13.164(1) A, V = 2690.8(2) A3, Dc = 1.491 g cm-3, Z = 4, F(000) = 1236, lambda(MoKa) = 0.71073 A, mi = 1.01 mm-1, R = 0.025, wR = 0.036 (w-1 = s2Fo + 0.0008Fo2), S = 1.03 for 2502 reflections with Inet gt 2sInet out of 2958 independent diffraction data and 173 variable parameters. The structure is built up of individual [Cu(H2O)(py)2(sac)2] molecules. The copper atom is bonded to two pyridine nitrogens and two saccharinato nitrogen atoms as well as to the water molecule forming thereby a slightly distorted square pyramid. The copper atom lying on a two-fold rotation axis (together with the water oxygen atom) is 0.2209(7) A above the basic square plane formed by the four nitrogen atoms. The bond distances in the coordination polyhedron are: Cu-Npy 2.040(2) A, Cu-Nsac 2.032(2) A, Cu-Ow 2.177(2) A. The N-Cu-N bond angles amount 88.67(8), 89.97(8), 167.36(9), and 167.69(8)o, respectively. The values of the Ow-Cu-N angles are 96.16(6) and 96.32(6)o, respectively. The pyridine molecule is almost perpendicular to the plane of the saccharinato ligand. The angle between the corresponding best planes is 86.8(1)o. The water molecule is hydrogen bonded to the saccharinato carbonyl oxygen atom forming an infinite chain of hydrogen bonds along the z-axis. The OwˇˇˇOco distance is 2.698(3) A.

Saccharin; copper complex; crystal structure; hydrogen bonding

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