Structural Feature of a Hexa-DMSO Cobalt(II) Complex: <i>Pseudo</i>-<i>S</i>₆ Symmetry and <i>Pseudo</i>-<i>C</i>_2v Deformation

Abstract

Previously, a crystal structure of hexa-DMF cobalt(II) complex [Co(DMF)6](BPh4)2 (DMF = N,N-dimethylformamide) was determined, 1 and its coordination geometry around cobalt(II) ion was found to be trigonally compressed. The distortion of this type is related to the splitting pattern of the ground term caused by the spin-orbit coupling; 2 controlling the distortion leads to controlling the magnetic behavior. Moreover, the structure of the complex could be approximated to a rather rare S6 point group. In this study we studied a dimethylsulfoxide (DMSO) derivative with the aim of revealing its structural feature: symmetry and distortion. A DMSO derivative was prepared by refluxing a DMSO solution (2.0 ml) of cobalt(II) nitrate hexahydrate (1.0 mmol, 0.29 g) for 0.5 hour; also, the addition of a DMSO solution of sodium tetraphenylborate (2.0 mmol, 0.68 g) resulted in the precipitation of purple microcrystals. Single-crystals suitable for X-ray analysis were obtained by recrystallization of the microcrystals from DMSO. The crystal data are included in Table 1. The structure was solved by direct methods and expanded using Fourier techniques. The non-hydrogen atoms were refined anisotropically, and hydrogen atoms were refined using the riding model. The final cycle of full-matrix least-squares refinement on F 2 was let to satisfactory converge with R1 = 0.0539 [I > 2s(I)]. The crystal consists of complex cations [Co(DMSO)6] 2+ and tetraphenylborate anions in a 1:2 molar ratio. Although several complexes containing [Co(DMSO)6] 2+ have been reported, 3-6 the present tetraphenylborate derivative has not been reported. The chemical structure is shown in Fig. 1, and an ORTEP view for the complex cation is shown in Fig. 2. In the complex cation, X-ray Structure Analysis Online

Dimethyl sulfoxide as a strongly coordinating solvent: 3′,4′-dihydroxyflavone-Cu(II)-DMSO system case study

“…of fully protonated systems, stronger interaction was found between Cu and DMSO compared to the Cu-DHF bond (r BCP and DI values in Table 3). Such strong coordination can play a key role in ligand replacement reaction when studying various transition metal complexes as competitive reaction between a ligand and DMSO (Sudo et al, 2012). On the contrary, in systems containing deprotonated DHF moiety, the Cu-O bond between Cu and DHF (-2H) is stronger than that between Cu and the DMSO molecule/molecules.…”

Crystal Structure of a Mononuclear Iron(III) Complex, Chloridopentakis(dimethylsulfoxide-κ<i>O</i>)iron(III) Bis(tetraphenylborate)

“…In some related hexakis-dmso complexes, [1][2][3] random at a first glance, but a rotational structure is seen from a direction, as shown in Fig. 3.…”

“…1 In the case of the [Zn(dmso)6](BPh4)2 complex (dmso: dimethylsulfoxide), the crystallographically obtained structure was different from the predicted most stable structure, but it was understood that this structure would be appropriately deformed to reduce the volume. In this study, with the aim of expanding the hexakis-dmso system [1][2][3] to the pentakis-dmso system, [FeCl(dmso)5](BPh4)2 [chloridopentakis(dimethylsulfoxide-κO)iron(III) bis(tetraphenylborate)] was prepared, and its crystal structure was determined by the single-crystal X-ray method.…”

Structural Feature of an Octakis-DMSO Cerium(III) Complex: Tetragonal Antiprismatic Coordination Geometry along the <i>c</i> Axis

“…1,2 Although their elemental compositions are similar, the crystal structures are significantly different, mainly because of a distortion around the cobalt(II) ion caused by the spin-orbit coupling. 1 Since lanthanide complexes are another group with significant spinorbit coupling, there has been considerable interest in the magnetic properties. In this study we investigated the crystal structure of the [Ce(DMSO)8](BPh4)3 complex with the aim to reveal the relationship with the spin-orbit coupling.…”