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[Tris(3,5-di­phenyl­pyrazol­yl)hydro­borato]nickel(II) bromide

aMolecular Technology Research Unit, Department of Chemistry, Walailak University, Thasala, Nakhon Si Thammarat 80161, Thailand, and bDepartment of Chemistry, Faculty of Science, University of Sheffield, Brook Hill, Sheffield S3 7HF, England
*Correspondence e-mail: hdavid@wu.ac.th

(Received 14 May 2009; accepted 6 June 2009; online 13 June 2009)

In the title tris­(pyrazol­yl)borate (TpPh2) complex, [NiBr(C45H34BN6)], the Ni, Br and B atoms lie on a crystallographic threefold axis and a distorted NiN3Br tetra­hedral geometry arises for the metal ion. In the crystal, C—H⋯(C=C) and C—H⋯π inter­actions help to establish the polar crystal packing.

Related literature

For other TpRNiX (X = Cl, Br) complexes, see: Desrochers et al. (2003[Desrochers, P. J., LeLievre, L., Johnson, R. J., Lamb, B. T., Phelps, A. L., Cordes, A. W., Gu, W. & Cramer, S. P. (2003). Inorg. Chem. 42, 7945-7950.], 2006[Desrochers, P. J., Telser, J., Zvyagin, S. A., Ozarowski, A., Krzystek, J. & Vicic, D. A. (2006). Inorg. Chem. 45, 8930-8941.]); Kunrath et al. (2003[Kunrath, F. A., de Souza, R. F., Casagrande, O. L. Jr, Brooks, N. R. & Young, V. G. Jr (2003). Organometallics, 22, 4739-4743.]); Uehara et al. (2002[Uehara, K., Hikichi, S. & Akita, M. (2002). J. Chem. Soc. Dalton Trans. pp. 3529-3538.]); Guo et al. (1998[Guo, S., Ding, E., Yin, Y. & Yu, K. (1998). Polyhedron, 17, 3841-3849.]); Harding et al. (2007[Harding, D. J., Harding, P., Adams, H. & Tuntulani, T. (2007). Inorg. Chim. Acta, 360, 3335-3340.]). For ionic radius data, see: Shannon (1976[Shannon, R. D. (1976). Acta Cryst. A32, 751-767.]).

[Scheme 1]

Experimental

Crystal data
  • [NiBr(C45H34BN6)]

  • Mr = 808.21

  • Trigonal, R 3

  • a = 12.8227 (8) Å

  • c = 19.327 (3) Å

  • V = 2752.0 (5) Å3

  • Z = 3

  • Mo Kα radiation

  • μ = 1.66 mm−1

  • T = 150 K

  • 0.24 × 0.24 × 0.21 mm

Data collection
  • Bruker SMART CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 1997[Bruker (1997). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.691, Tmax = 0.722

  • 5609 measured reflections

  • 2075 independent reflections

  • 1943 reflections with I > 2σ(I)

  • Rint = 0.037

Refinement
  • R[F2 > 2σ(F2)] = 0.028

  • wR(F2) = 0.063

  • S = 1.06

  • 2075 reflections

  • 163 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.27 e Å−3

  • Δρmin = −0.29 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 670 Friedel pairs

  • Flack parameter: 0.020 (8)

Table 1
Selected geometric parameters (Å, °)

Ni1—Br1 2.3523 (6)
Ni1—N1 2.041 (2)
N1—Ni1—N1i 93.11 (8)
N1—Ni1—Br1 123.04 (6)
Symmetry code: (i) -x+y+1, -x+1, z.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C5—H5⋯Cg1ii 0.95 2.73 3.589 (3) 151
Symmetry code: (ii) [-x+y+{\script{5\over 3}}, -x+{\script{1\over 3}}, z-{\script{2\over 3}}].

Data collection: SMART (Bruker, 1997[Bruker (1997). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 1997[Bruker (1997). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Tris(pyrazolyl)borates are versatile and popular ligands in coordination chemistry with many complexes now known. Despite the C3 symmetry present in many tris(pyrazolyl)borate ligands few tetrahedral complexes crystallize in space groups containing a C3 axis (Desrochers et al., 2003, 2006; Kunrath et al., 2003; Uehara et al., 2002). Rare examples which do contain a C3 axis include [TpPh2NiCl] and [TpPh2Ni(OAc)] despite the later being formally five-coordinate (Guo et al., 1998; Harding et al., 2007). In the following paper we report a further example namely, the title compound, [TpPh2NiBr], (I).

The reaction of NiBr2.2H2O with KTpPh2 readily affords the title complex as a red-purple solid in moderate yield. Crystals were grown by allowing hexanes to diffuse into a concentrated solution of the complex in CH2Cl2. The compound crystallizes in the trigonal R3 space group. The structure is shown in Figure 1 while important bond lengths and angles are given in the supporting tables. The geometry around the nickel centre is best described as distorted tetrahedral {N1—Ni—N1i = 93.11 (8), N1—Ni—Br1 = 123.04 (6)}. The Ni—N bond lengths are very slightly longer by ca. 0.01 Å than those found in [TpPh2NiCl] (Guo et al., 1998). A similar difference is observed in the structures of [Tp*NiCl] and [Tp*NiBr] (Desrochers et al., 2003, 2006). The Ni—Br distance is 2.3523 (6) Å, ca 0.15 Å longer than the corresponding Ni—Cl distance in [TpPh2NiCl], and consistent with the difference in the bromine and chlorine covalent radii (0.15 Å; Shannon, 1976). Interestingly, the Ni—Br bond length in (I) is significantly longer than that observed for [Tp*NiBr] (2.291 (2) Å). A similar increase, albeit not so marked, is also found between [TpPh2NiCl] and [Tp*NiCl] (ΔNi-Cl = 0.03 Å) suggesting that the larger TpPh2 ligand may be responsible for the longer nickel-halide bond distances.

The crystal packing in the structure of (I) contains several C—H···π interactions between the phenyl rings of neighbouring TpPh2 ligands (see Figure 2). The hydrogen atoms H6 and H11 are directed at the π bonds between C1—N1 and C4—C5, respectively {(C1—N1)π···H6 2.657 (3) Å; (C4—C5)π···H11 2.834 (5) Å} while H5 interacts with a phenyl ring (Cg1···H5 2.730 (3) Å; Cg1 is the centroid of ring C10—C15). Similar interactions occur on all three faces of the TpPh2 ligand creating a network of triangular columns such that all the [TpPh2NiBr] molecules point in the same direction and the phenyl rings adopt a propeller configuration.

Related literature top

For other TpRNiX (X = Cl, Br) complexes, see: Desrochers et al. (2003); Desrochers et al. (2006); Kunrath et al. (2003); Uehara et al. (2002); Guo et al. (1998); Harding et al. (2007). For ionic radius data, see: Shannon (1976).

Experimental top

NiBr2.2H2O (34 mg, 0.14 mmol) was dissolved in THF (5 ml) giving a green solution and then stirred for 5 min. KTpPh2 (95 mg, 0.15 mmol) was dissolved in THF (5 ml) giving a pale yellow solution. Addition of the KTpPh2 solution to the Ni solution resulted in a colour change to a red-pink solution. The solution was stirred for 16 hrs. The solution was reduced to dryness, redissolved in fresh THF (2 ml) and filtered through celite. The purple-pink solution was layered with hexanes (10 ml). After two days purple-pink blocks of (I) appeared. These were washed with EtOH (3 x 3 ml) and hexanes (2 x 5 ml) (59 mg, 54%). νmax(KBr)/cm-1 3059w, 2966w, 2854w (νCH), 2626w (νBH). δH (300 MHz; CDCl3; SiMe4), 7.63 (br m, m- and p-Ph, 18H), 8.53 (br s, o-Ph, 6H), 8.86 (br s, o-Ph, 6H). UV–Vis λmax(CH2Cl2)/nm 318 (ε/dm3mol-1cm-1 3140), 502 (600), 828 (120), 926 (160). m/z (ESI) 727 [M—Br-]+. Anal. Calc. for C45H34N6BBrNi [TpPh2NiBr]: C, 66.87; H, 4.24; N 10.40 Found: C, 66.62; H, 4.29; N, 10.17%

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997); data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) with displacement ellipsoids drawn at the 50% probability level. [Symmetry codes:(i) -x + y+1, -x + 1, z; (ii) -y + 1, x-y, z].
[Figure 2] Fig. 2. The molecular packing in (I) showing the three C—H···π interactions. Only selected atoms are labelled or shown for clairty [Symmetry codes:(i) 4/3 - x + y, 2/3 - x, -1/3 + z; (ii) 4/3 - y, -1/3 + x-y, -1/3 + z].
[Tris(3,5-diphenylpyrazolyl)hydroborato]nickel(II) bromide top
Crystal data top
[NiBr(C45H34BN6)]Dx = 1.463 Mg m3
Mr = 808.21Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3Cell parameters from 2851 reflections
Hall symbol: R 3θ = 2.8–30.6°
a = 12.8227 (8) ŵ = 1.66 mm1
c = 19.327 (3) ÅT = 150 K
V = 2752.0 (5) Å3Block, purple–pink
Z = 30.24 × 0.24 × 0.21 mm
F(000) = 1242
Data collection top
Bruker SMART CCD
diffractometer
2075 independent reflections
Radiation source: fine-focus sealed tube1943 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.037
Detector resolution: 100 pixels mm-1θmax = 27.5°, θmin = 2.1°
ϕ scansh = 1616
Absorption correction: multi-scan
(SADABS; Bruker, 1997)
k = 1116
Tmin = 0.691, Tmax = 0.722l = 2125
5609 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.028H-atom parameters constrained
wR(F2) = 0.063 w = 1/[σ2(Fo2) + (0.0169P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max = 0.001
2075 reflectionsΔρmax = 0.27 e Å3
163 parametersΔρmin = 0.29 e Å3
1 restraintAbsolute structure: Flack (1983), 670 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.020 (8)
Crystal data top
[NiBr(C45H34BN6)]Z = 3
Mr = 808.21Mo Kα radiation
Trigonal, R3µ = 1.66 mm1
a = 12.8227 (8) ÅT = 150 K
c = 19.327 (3) Å0.24 × 0.24 × 0.21 mm
V = 2752.0 (5) Å3
Data collection top
Bruker SMART CCD
diffractometer
2075 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 1997)
1943 reflections with I > 2σ(I)
Tmin = 0.691, Tmax = 0.722Rint = 0.037
5609 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.028H-atom parameters constrained
wR(F2) = 0.063Δρmax = 0.27 e Å3
S = 1.06Δρmin = 0.29 e Å3
2075 reflectionsAbsolute structure: Flack (1983), 670 Friedel pairs
163 parametersAbsolute structure parameter: 0.020 (8)
1 restraint
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Br10.66670.33330.732391 (16)0.02249 (14)
Ni10.66670.33330.61068 (2)0.01335 (14)
N10.75319 (18)0.26622 (19)0.55312 (10)0.0127 (4)
N20.75175 (19)0.29001 (19)0.48407 (10)0.0128 (4)
B10.66670.33330.4567 (3)0.0139 (10)
H1B0.66670.33330.39830.017*
C10.8082 (2)0.2003 (2)0.55910 (12)0.0146 (5)
C20.8419 (3)0.1815 (3)0.49355 (13)0.0166 (6)
H20.88120.13730.48290.020*
C30.8064 (2)0.2405 (2)0.44716 (12)0.0136 (5)
C40.8224 (3)0.2532 (3)0.37198 (14)0.0135 (5)
C50.7922 (2)0.1509 (2)0.33065 (13)0.0173 (6)
H50.76010.07380.35150.021*
C60.8094 (3)0.1632 (3)0.25990 (16)0.0182 (7)
H60.78900.09420.23250.022*
C70.8557 (2)0.2743 (3)0.22844 (13)0.0201 (6)
H70.86680.28140.17970.024*
C80.8860 (3)0.3759 (3)0.26839 (13)0.0215 (6)
H80.91790.45250.24690.026*
C90.8698 (3)0.3652 (3)0.33951 (14)0.0190 (6)
H90.89130.43500.36650.023*
C100.8239 (2)0.1510 (3)0.62468 (13)0.0163 (6)
C110.8460 (2)0.2131 (3)0.68680 (14)0.0185 (6)
H110.85640.29190.68720.022*
C120.8530 (3)0.1605 (3)0.74866 (17)0.0230 (7)
H120.86500.20230.79120.028*
C130.8422 (3)0.0472 (3)0.74807 (16)0.0269 (7)
H130.84680.01130.79010.032*
C140.8246 (3)0.0137 (3)0.68574 (15)0.0234 (7)
H140.81910.09040.68490.028*
C150.8150 (3)0.0381 (3)0.62476 (16)0.0209 (6)
H150.80220.00410.58240.025*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.02665 (19)0.02665 (19)0.0142 (2)0.01332 (9)0.0000.000
Ni10.0140 (2)0.0140 (2)0.0120 (3)0.00702 (10)0.0000.000
N10.0107 (10)0.0149 (11)0.0121 (9)0.0061 (9)0.0007 (8)0.0007 (8)
N20.0137 (11)0.0146 (11)0.0096 (8)0.0068 (9)0.0007 (8)0.0006 (8)
B10.0112 (15)0.0112 (15)0.019 (2)0.0056 (8)0.0000.000
C10.0121 (13)0.0105 (13)0.0199 (12)0.0047 (11)0.0016 (10)0.0005 (10)
C20.0186 (14)0.0165 (15)0.0191 (16)0.0122 (13)0.0028 (13)0.0009 (12)
C30.0097 (13)0.0094 (12)0.0189 (12)0.0026 (11)0.0001 (9)0.0010 (9)
C40.0106 (13)0.0148 (14)0.0169 (12)0.0077 (11)0.0010 (10)0.0012 (11)
C50.0171 (15)0.0124 (14)0.0221 (13)0.0071 (12)0.0005 (11)0.0031 (11)
C60.0191 (16)0.0155 (15)0.0234 (16)0.0113 (13)0.0015 (13)0.0039 (13)
C70.0180 (15)0.0237 (15)0.0153 (12)0.0080 (13)0.0044 (11)0.0003 (11)
C80.0210 (15)0.0179 (15)0.0210 (12)0.0062 (12)0.0060 (11)0.0053 (11)
C90.0199 (16)0.0172 (15)0.0193 (13)0.0087 (13)0.0016 (11)0.0029 (11)
C100.0089 (13)0.0166 (14)0.0215 (13)0.0049 (11)0.0001 (10)0.0043 (11)
C110.0136 (14)0.0155 (14)0.0233 (13)0.0050 (12)0.0050 (11)0.0012 (11)
C120.0204 (17)0.0291 (19)0.0180 (15)0.0112 (15)0.0034 (13)0.0002 (14)
C130.0206 (16)0.0304 (17)0.0268 (14)0.0105 (14)0.0022 (13)0.0126 (13)
C140.0206 (16)0.0195 (16)0.0333 (16)0.0124 (13)0.0008 (12)0.0075 (13)
C150.0185 (15)0.0194 (16)0.0257 (14)0.0101 (14)0.0019 (12)0.0011 (12)
Geometric parameters (Å, º) top
Ni1—Br12.3523 (6)C5—H50.9500
Ni1—N12.041 (2)C6—C71.380 (4)
Ni1—N1i2.041 (2)C6—H60.9500
Ni1—N1ii2.041 (2)C7—C81.392 (4)
N1—C11.350 (3)C7—H70.9500
N1—N21.371 (3)C8—C91.387 (4)
N2—C31.360 (3)C8—H80.9500
N2—B11.544 (3)C9—H90.9500
B1—N2i1.544 (3)C10—C111.389 (4)
B1—N2ii1.544 (3)C10—C151.394 (4)
B1—H1B1.1278C11—C121.397 (4)
C1—C21.398 (4)C11—H110.9500
C1—C101.475 (3)C12—C131.390 (5)
C2—C31.388 (3)C12—H120.9500
C2—H20.9500C13—C141.391 (5)
C3—C41.465 (4)C13—H130.9500
C4—C91.397 (4)C14—C151.388 (4)
C4—C51.415 (4)C14—H140.9500
C5—C61.381 (4)C15—H150.9500
N1—Ni1—N1i93.11 (8)C4—C5—H5120.0
N1—Ni1—N1ii93.11 (8)C7—C6—C5121.0 (3)
N1i—Ni1—N1ii93.11 (8)C7—C6—H6119.5
N1—Ni1—Br1123.04 (6)C5—C6—H6119.5
N1i—Ni1—Br1123.04 (6)C6—C7—C8119.7 (2)
N1ii—Ni1—Br1123.04 (6)C6—C7—H7120.1
C1—N1—N2106.99 (19)C8—C7—H7120.1
C1—N1—Ni1141.45 (17)C9—C8—C7119.9 (3)
N2—N1—Ni1111.47 (15)C9—C8—H8120.0
C3—N2—N1109.82 (19)C7—C8—H8120.0
C3—N2—B1127.6 (2)C8—C9—C4120.9 (3)
N1—N2—B1120.3 (2)C8—C9—H9119.5
N2—B1—N2i108.89 (19)C4—C9—H9119.5
N2—B1—N2ii108.89 (19)C11—C10—C15118.8 (3)
N2i—B1—N2ii108.89 (19)C11—C10—C1121.9 (3)
N2—B1—H1B110.0C15—C10—C1119.2 (2)
N2i—B1—H1B110.0C10—C11—C12120.4 (3)
N2ii—B1—H1B110.0C10—C11—H11119.8
N1—C1—C2109.5 (2)C12—C11—H11119.8
N1—C1—C10124.6 (2)C13—C12—C11120.1 (3)
C2—C1—C10125.8 (2)C13—C12—H12120.0
C3—C2—C1106.1 (2)C11—C12—H12120.0
C3—C2—H2127.0C14—C13—C12119.8 (3)
C1—C2—H2127.0C14—C13—H13120.1
N2—C3—C2107.6 (2)C12—C13—H13120.1
N2—C3—C4122.9 (2)C15—C14—C13119.7 (3)
C2—C3—C4129.5 (2)C15—C14—H14120.2
C9—C4—C5118.4 (2)C13—C14—H14120.2
C9—C4—C3121.7 (3)C14—C15—C10121.1 (3)
C5—C4—C3119.9 (2)C14—C15—H15119.4
C6—C5—C4119.9 (3)C10—C15—H15119.4
C6—C5—H5120.0
Symmetry codes: (i) x+y+1, x+1, z; (ii) y+1, xy, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C5—H5···Cg1iii0.952.733.589 (3)151
Symmetry code: (iii) x+y+5/3, x+1/3, z2/3.

Experimental details

Crystal data
Chemical formula[NiBr(C45H34BN6)]
Mr808.21
Crystal system, space groupTrigonal, R3
Temperature (K)150
a, c (Å)12.8227 (8), 19.327 (3)
V3)2752.0 (5)
Z3
Radiation typeMo Kα
µ (mm1)1.66
Crystal size (mm)0.24 × 0.24 × 0.21
Data collection
DiffractometerBruker SMART CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 1997)
Tmin, Tmax0.691, 0.722
No. of measured, independent and
observed [I > 2σ(I)] reflections
5609, 2075, 1943
Rint0.037
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.028, 0.063, 1.06
No. of reflections2075
No. of parameters163
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.27, 0.29
Absolute structureFlack (1983), 670 Friedel pairs
Absolute structure parameter0.020 (8)

Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected geometric parameters (Å, º) top
Ni1—Br12.3523 (6)Ni1—N12.041 (2)
N1—Ni1—N1i93.11 (8)N1—Ni1—Br1123.04 (6)
Symmetry code: (i) x+y+1, x+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C5—H5···Cg1ii0.952.733.589 (3)151
Symmetry code: (ii) x+y+5/3, x+1/3, z2/3.
 

Acknowledgements

The authors gratefully acknowledge the Thailand Research Fund (grant No. RMU5080029) and the National Research Council of Thailand (grant No. WU51106) for support of this work.

References

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