Crystal structure of chlorido{tris[2-(isopropylsulfanyl)phenyl]phosphane-κ4 P,S,S′,S′′}nickel(II) trifluoromethanesulfonate

The complex cation of the title compound has a five-coordinate slightly distorted trigonal–bipyramidal structure in which three S atoms are located in the equatorial positions, and one P and one Cl atom in the apical positions.


Chemical context
Unusual five-coordinate nickel(II) complexes have been often obtained by use of polydentate ligands such as tripodal tetradentate ligands (Orioli, 1971;Morassi et al., 1973;Hierso et al., 2003). A variety of tripodal tetradentate ligands having phosphines and/or amines as coordinating sites have been used for the synthesis of five-coordinate nickel(II) complexes. However, for PS 3 -type tripodal tetradentate ligands in which three thioether moieties are tethered to a phosphine moiety, only one crystal structure (Haugen & Eisenberg, 1969) had been reported before we started our studies. Recently, we have synthesized new PS 3 -type tripodal tetradentate ligands, tris(2-isopropylthiophenyl)phosphine, 1a and tris(2-tertbutylthiophenyl)phosphine, 1b (Fig. 1), and reported the syntheses and properties of their group 10 metal complexes (Takeda et al., 2010(Takeda et al., , 2016. Reaction of 1a with NiCl 2 Á6H 2 O in ISSN 2056-9890 Figure 1 Synthesis of nickel(II) complexes bearing the PS 3 -type tripodal tetradentate ligand. the presence of NaBF 4 gave the corresponding cationic fivecoordinate nickel(II) complex, 2, while the reaction of 1b with NiCl 2 Á6H 2 O resulted in the elimination of t-BuCl to afford a neutral five-coordinate nickel(II) complex, 4 (Fig. 1). In this paper, we describe the structure of the title compound, [NiCl(L)]CF 3 SO 3 (L = 1a), 3, which was prepared by reaction of 1a with NiCl 2 Á6H 2 O in the presence of an excess amount of NaCF 3 SO 3 (Fig. 1).

Figure 3
The conformation diagrams of the Ni(SR) 3 moieties (R = i-Pr or Me) for 3 (A) and 5 (B), viewed along the Ni-Cl bond.

Supramolecular features
In the crystal of 3, there are some hydrogen bonds between the cation and the anion (Fig. 4). The cation and the anion are linked into a tape structure along the b-axis direction via C-HÁ Á ÁO and C-HÁ Á ÁF hydrogen bonds (C2-H2Á Á ÁO1 i , C8-H8Á Á ÁF2A iii , C8-H8Á Á ÁF2B iii , C20-H20Á Á ÁO1 i and C22-H22Á Á ÁO2A v ; symmetry codes as in Table 1) . The tapes are further linked by weak C-HÁ Á ÁO and C-HÁ Á ÁF hydrogen bonds formed between the cation and the minor component of the disordered anion (C5-H5Á Á ÁO3B ii and C18-H18BÁ Á ÁF3B iv ; Table 1), forming a three-dimensional network (Figs. 5 and 6). , are different from that of complex 3. The former is an anionic nickel(III) complex having three thiolato ( À SR), one chlorido and one phosphine ligands, and the latter, 4, is a neutral nickel(II) complex having two thioether, one thiolato, one chlorido and one phosphine ligands.

Figure 5
A packing diagram of 3, viewed along the a axis. The C-HÁ Á ÁO and C-HÁ Á ÁF hydrogen bonds are shown as dashed lines.

Refinement
Crystal data, data collection and structure refinement details are summarized in Table 3. The H atoms were positioned geometrically (C-H = 0.95-1.00 Å ) and refined as riding atoms with U iso (H) =1.5U eq (C) for methyl or 1.2U eq (C) for aromatic and methine H atoms. The methyl groups were allowed to rotate freely around the C-C bond. The triflate anion exhibits disorder and was modelled with occupancies of 0.629 (17) and 0.371 (17). The geometric parameters of the minor component were restrained to be similar to those of the major component by using SAME restraint. In addition, one of the methyl groups in the complex cation exhibits disorder and was modelled with occupancies of 0.786 (14) and 0.214 (14). The C25-C27A and C25-C27B bond lengths were restrained to be equal to each other by using SADI restraint.  Data collection: CrystalClear (Rigaku, 2013); cell refinement: CrystalClear (Rigaku, 2013); data reduction: CrystalClear (Rigaku, 2013); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure:

Funding information
SHELXL2014 (Sheldrick, 2015b); molecular graphics: Yadokari-XG (Wakita, 2001;Kabuto et al., 2009); software used to prepare material for publication: Yadokari-XG (Wakita, 2001;Kabuto et al., 2009) and publCIF (Westrip, 2010). Special details Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.