Crystal structure of cis bis(4-benzoyl-3-methyl-1-phenyl pyrazol-5-one)- cis bis(methanol)-cobalt(II), C 36 H 34 CoN 4 O 6 Omoruyi G. Idemudia *, I , Alexander P. Sadimenko I and Eric C. Hosten II I Department of Chemistry, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa II Department of Chemistry, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031, South Africa Received July 02, 2014, accepted March 05, 2015, available online March 10, 2015, CCDC no. 1267/4260 Abstract C 36 H 34 CoN 4 O 6 , monoclinic, P2 1 /n (no. 14), a = 13.9021(5) Å, b = 13.9557(5) Å, c = 17.3379(6) Å, b = 101.254(2)°, V = 3299.1 Å 3 , Z = 4, R gt (F) = 0.0316, wR ref (F 2 ) = 0.0869, T = 200 K. Source of material To a solution of Bmpp-Ph (3-methyl-1-phenyl-4-[(phenyl)(2- phenylhydrazin-1-yl)methylidene]-1H-pyrazol-5(4H)-one, 2 mmol, 0.74 g) in hot ethanol (40 mL) was added in drops aqueous solution of CoCl 2 ×4H 2 O (1 mmol, 0.20 g) while stirring under re- flux. After 4 h of reflux, the pink precipitate was filtered, washed with ethanol/water (1:1), dried at room temperature and stored over fused CaCl 2 . Slow evaporation of a solution of the resultant pink solid in methanol afforded orange crystals of an unprece- dented Co(Bmpp) 2 (MeOH) 2 suitable for x-ray crystallography. Experimental details Carbon-bound H atoms were placed in calculated positions and were included in the refinement in the riding model approxima- tion, with U iso (H) set to 1.2 U eq (C). The H atoms of the methyl groups were allowed to rotate with a fixed angle around the C–C bond to best fit the experimental electron density (HFIX 137 in the SHELX program suite [11]), with U iso (H) set to 1.5 U eq (C). The oxygen-bound H atoms were located on a difference Fourier map and refined freely. Discussion As an analytical reagent acylpyrazolones have been employed as good spectroscopic chelating ligand for the determination of met- als in trace amounts [1], they have also been used as excellent cat- alysts [2]. They are bioactive di-ketone heterocycles [3] and are capable of forming Schiff bases with amino groups [4, 5]. Suc- cessful coordination of acylpyrazolone diketones with transition metals have been reported to increase their catalytic properties [6]. We have already reported a bioactive cobalt complex of acyl- pyrazolone [7]. In view of our interest in metal complexes of Schiff bases, presented herein is the molecular and crystal struc- ture of a new cobalt complex. The studies on the bioactive and catalytic activities of the title compound are presently ongoing. In the crystal structure the title complex has an octahedral coordina- tion geometry consisting of two Bmpp ligands and two coordinat- ing methanol molecules. Each 4-benzoyl-3-methyl-1-phenyl pyrazol-5-one (Bmpp) ligand is deprotonated with the negative charge delocalized. The Bmpp ligands occur cis to each other sim- ilarly to the cis complex reported by Wu et al. [8] which has one methanol and one ethanol ligand. In contrast the complex we re- ported earlier [7] with two coordinating ethanol ligands has two Bmpp ligands trans to each other. The average Bmpp Co–O bond length here is 2.070(33) Å which is very similar to the mixed etha- nol methanol complex [8] where the average bond length is 2.071(29) Å. In the complex with the two trans ethanols [7] the average Co–O bond length is only slightly shorter at 2.038(36) Å. The title complex is obviously non-centrosym-metrical therefore the two Bmpp ligands having different geometrical configura- tions. In the first ligand the dihedral angle between the least square planes through the phenyl rings is 20.76(9)°, while in the second ligand the dihedral angle is larger at 86.25(10)°. There are a number of potential intramolecular hydrogen bonds with the shortest being the C216–H216×××O21 interaction with length 2.24 Å. There is also an intramolecular C–H×××p ring interaction C222–H222 with the pyrazole ring N11, N12, C11–C13 of length 2.55 Å to the ring centroid. In the crystal structure adjacent com- plexes are linked together with two intermolecular O3–H3×××O22 interactions with length 1.94(2) Å which in terms of graph-set 162 Z. Kristallogr. NCS 230 (2015) 162-164 / DOI 10.1515/ncrs-2014-0239 © 2015 Walter de Gruyter GmbH, Berlin/Munich/Boston Crystal: orange blocks, size 0.365´0.396´0.444 mm Wavelength: Mo K a radiation (0.71073 Å) m: 5.72 cm -1 Diffractometer, scan mode: Bruker APEX-II CCD, j and w 2q max : 56.77° N(hkl) measured , N(hkl) unique : 48511, 8246 Criterion for I obs , N(hkl) gt : I obs >2 s(I obs ), 6934 N(param) refined : 436 Programs: SHELX, SADABS, SAINT, ShelXLe, ORTEP-3, PLATON, MERCURY [11–16] Table 1. Data collection and handling. _____________ * Correspondence author (e-mail: oidemudia@ufh.ac.za)