Synthesis, crystal and molecular structure of [Co(L)3](OH)Cl · H3Ssal) · H2O, where L is benzhydrazide and H3Ssal is 5-sulfosalycilic acid

Abstract

Hydrazides of carboxylic acids are bioactive, and some of them are applied in pharmacology. However, the presence of three functional groups (C=O, -NH-, and -NH 2 ), which are able to interact with each other and to act as donating groups in complexation with d metals, makes hydrazides of carboxylic acids and their coordination compounds interesting for structural studies. X ray diffraction data for a number of hydrazide coordination compounds with metals, including some benzhydrazide complexes, are found in [1]. Literature data on the structures of benzhydrazide coordination compounds with 3d metals concern only complexes with inorganic anions. Information on similar complexes with carboxylates is unavailable.In this work, the coordination compound [CoL 3 ](OH)Cl(Н 3 Ssal) ⋅ H 2 O (I), where L is benzhy drazide (hydrazide of benzoic acid), and Н 3 Ssal is 5 sulfosalycilic acid, has been synthesized and studied by IR spectroscopy and X ray diffraction. EXPERIMENTALSynthesis of complex I. CoCl 2 ⋅ 6H 2 O (2.38 g, 0.01 mol) was dissolved in water (5 mL), thereupon NaOH (0.4 g, 0.01 mol) was added. The settled precipitate was fil tered out, carefully washed with water, and added in portions to a solution of sulfosalycilic acid (2.18 g, 0.01 mol) in water (5 mL). To the resulting solutions, ben zhydrazide (4.08 g, 0.03 mol) dissolved in water (30 mL) was added in portions under stirring. After the precipitate settled, it was washed with water several times and dried in a desiccator over CaCl 2 to a constant weight.Crystals suitable for X ray diffraction analysis were obtained by recrystallizing the powder product from water.IR absorption spectra were recorded as KBr pellets on a Frontier Perkin Elmer FTIR spectrometer (4000-350 cm -1 ). X ray diffraction analysis. Prismatic crystals of complex I (С 28 Н 28 ClCoN 6 O 11 S) are orange and tri clinic: а = 9.948(2) Å, b = 13.288(3) Å, c = 14.710(3) Å, α = 109.39(3)°, β = 95.60(3)°, γ = 110.38°, V = 1668.7(6) Å 3 , FW = 751.0, F(000) = 772, ρ calcd = 1.495 g/cm 3 , μ = 5.936 g/cm 3 , Z = 2, space group РThe intensities of 5744 independent non zero reflections (2803 reflections were refined) were mea sured on an Enraf Nonius CAD 4 diffractometer (CuK α radiation, graphite monochromator, θ/2θ scan ning, θ max = 70°).The structure was solved and refined by least squares (on F 2 ) using the SHELXL 97 software [2]. Hydrogen atoms were located in calculated positions and refined isotropically with the parameter U H , which was 1.2 times higher than the thermal parameter of a corresponding non hydrogen atom. Abstract-The coordination compound [Co(L) 3 ](OH)Cl(H 3 Ssal) ⋅ H 2 O (I) (L is benzhydrazide, and H 3 Ssal is 5 sulfosalycilic acid) has been synthesized and studied by IR spectroscopy and X ray diffraction. Orange crystals are triclinic: a = 9.948(2) Å, b = 12.288(3) Å, c = 14.710(3) Å, α = 109.39(3)°, β = 95.60(3)°, γ = 110.38(3)°, V = 1668.7(6) Å 3 , Z = 2, space group P Structural units of compound I are complex cat ions, OHand Clanions, sulfosalycilic acid molecules, a...