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Updated: Sep 23, 2025
Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of ChalcogenidoplumbatesII or IV
Published on: December 29, 2016
Crystal structure of di-μ-chlorido-bis-{chlorido-[(-)-5,6-pinenebi-pyridine]-cobalt(II)}
Massimo Varisco1, Aurelien Crochet2, Olimpia Mamula Steiner1
1University of Applied Sciences of Western Switzerland, HES-SO, HEIA-FR, Boulevard de Pérolles 80, CH-1700 Fribourg, Switzerland.
Abstract:
The crystal structure of [Co2Cl4(C17H18N2)2][CoCl2(C17H18N2)(H2O)] or [Co(L)Cl(μ-Cl)]2[Co(L)(Cl)2(OH2)], where L is the enanti-opure bidentate ligand (-)-5,6-pinenebi-pyridine (C17H18N2), has been determined. Crystals suitable for X-ray structure analysis were obtained by slow evaporation of an ethano-lic solution containing equimolar amounts of L and CoCl2·6H2O. The CoII cations all have a coordination number of five, and in each case the coordination polyhedron is a trigonal bipyramid. The Co-N bonds lengths range from 2.037 (7) to 2.195 (7) Å, and Co-Cl bonds lengths range from 2.284 (2) to 2.509 (2) Å. The asymmetric unit contains two discrete complexes, one dinuclear and the other mononuclear. Between the two mol-ecules, two types of inter-molecular inter-actions have been evidenced: π-π stackings involving the bi-pyridine units, and O-H⋯Cl hydrogen bonds between the hydrogen atoms of the aqua ligand coordinating to the mononuclear complex and the non-bridging chlorido ligand coordinating to the dinuclear mol-ecule. These inter-actions lead to a two-dimensional supra-molecular arrangement parallel to the ab plane.
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