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[2,6-Bis(di-tert-butyl­phosphinometh­yl)­phen­yl-κ3P,C1,P′](nitrato-κO)nickel(II)

aDepartment of Chemistry and Chemical Biology, MSC03 2060, 1 University of New Mexico, Albuquerque, NM 87131, USA, bDepartment of Chemistry, University of Washington, Seattle, WA 98195, USA, and cAdvanced Materials Laboratory, Sandia National Laboratories, 1001 University Boulevard SE, Albuquerque, NM 87106, USA
*Correspondence e-mail: rakemp@unm.edu

(Received 29 September 2008; accepted 7 October 2008; online 15 October 2008)

The NiII atom in the title compound, [Ni(C24H43P2)(NO3)], adopts a distorted square-planar geometry with the P atoms in a trans arrangement. The compound contains a twofold rotational axis with the nitrate group offset from this axis, except for an O atom of the nitrate group, generating two positions of 50% occupancy for the other atoms of the nitrate group.

Related literature

The synthetic preparation was adopted from that employed to prepare the Pd analogue (Cámpora et al., 2004[Cámpora, J., Palma, P., del Rio, D. & Álvarez, E. (2004). Organometallics, 23, 1652-1655.]). For the crystallographic characterization of the Pd analogue, see: Olsson et al. (2007[Olsson, D., Janse van Rensburg, J. M. & Wendt, O. F. (2007). Acta Cryst. E63, m1969.]). For the crystallographic characterization of the starting {2,6-bis­[(di-tert-butyl­phosphino)meth­yl]phenyl}chloridonickel complex, see: Boro et al. (2008[Boro, B. J., Dickie, D. A., Goldberg, K. I. & Kemp, R. A. (2008). Acta Cryst. E64, m1304.]). For related literature, see: Denney et al. (2006[Denney, M. C., Smythe, N. A., Cetto, K. L., Kemp, R. A. & Goldberg, K. I. (2006). J. Am. Chem. Soc. 128, 2508-2509.]); Johansson et al. (2007[Johansson, R., Öhrström, L. & Wendt, O. F. (2007). Cryst. Growth Des. 7, 1974-1979.]); Keith et al. (2006[Keith, J. M., Muller, R. P., Kemp, R. A., Goldberg, K. I., Goddard, W. A. III & Oxgaard, J. (2006). Inorg. Chem. 45, 9631-9633.]).

[Scheme 1]

Experimental

Crystal data
  • [Ni(C24H43P2)(NO3)]

  • Mr = 514.24

  • Orthorhombic, F d d 2

  • a = 24.0023 (14) Å

  • b = 12.6350 (6) Å

  • c = 17.6528 (6) Å

  • V = 5353.5 (4) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.87 mm−1

  • T = 225 (2) K

  • 0.50 × 0.40 × 0.20 mm

Data collection
  • Bruker X8 APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2004[Bruker (2004). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.671, Tmax = 0.846

  • 33484 measured reflections

  • 4078 independent reflections

  • 3703 reflections with I > 2σ(I)

  • Rint = 0.037

Refinement
  • R[F2 > 2σ(F2)] = 0.030

  • wR(F2) = 0.099

  • S = 0.81

  • 4078 reflections

  • 156 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.38 e Å−3

  • Δρmin = −0.38 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1976 Freidel pairs

  • Flack parameter: 0.012 (10)

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2; data reduction: APEX2; 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: DIAMOND (Brandenburg, 1999[Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: publCIF (Westrip, 2008[Westrip, S. P. (2008). publCIF. In preparation.]).

Supporting information


Comment top

The title compound, (I) (Fig. 1), was prepared from {2,6-bis[(di-tert-butylphosphino)methyl]phenyl}chloridonickel(II) (Boro et al., 2008) via a synthesis adopted from the preparation of the Pd analogue (Cámpora et al., 2004). Our research has been directed towards the activation of molecular oxygen using pincer complexes of the late transition metals (Denney et al., 2006; Keith et al., 2006). Compound (I) was prepared as a precursor along the path of the attempted synthesis of a NiII-hydroperoxide.

The compound is bisected by a twofold rotational axis running through C4, C1, Ni1, and O3. The nitrate group is offset from this axis with a C1—Ni1—O1 angle of 164.64 (11)°. As a result of this symmetry induced disorder the nitrate group occupies two positions each with 50% occupancy. The Ni1—O1 bond length 1.976 (3) Å is significantly shorter than the corresponding Pd—O bond length 2.164 (2) Å in the Pd analogue (Johansson et al. 2007). This not surprising, given the smaller size of the Ni atom. The M—C and M—P bonds were also shorter in the Ni compound compared to the Pd. The P—M—P angle, however was closer to the ideal linear geometry with Ni (168.87 (3)°) than Pd (163.41 (3)°).

In their report on the Pd analogue of (I), Johansson et al. (2007) observed non-traditional hydrogen bonding between one of the nitrato O atoms and a hydrogen from the methylene arm of the pincer ligand to form a zigzag chain. The C—H···O interaction measured 3.263 (4) Å (C···O) with an angle of 137°. The same pattern is observed in I (Fig. 2) between C5—H5b···O2, with corresponding measurements of 3.5616 (54) Å and 171.81 (18)°.

Related literature top

The synthetic preparation was adopted from that employed to prepare the Pd analogue (Cámpora et al., 2004). For the crystallographic characterization of the Pd analogue, see: Olsson et al. (2007). For the crystallographic characterization of the starting {2,6-bis[(di-tert-butylphosphino)methyl]phenyl}chloridonickel complex, see: Boro et al. (2008). For related literature, see: Denney et al. (2006); Johansson et al. (2007); Keith et al. (2006).

Experimental top

{2,6-Bis[(di-tert-butylphosphino)methyl]phenyl}chloronickel(II) (0.135 g, 0.28 mmol) and AgNO3 (0.05 g, 0.29 mmol) were combined with THF (20 ml) and the solution was stirred at room temperature for 48 h. The THF was then removed under vacuum and the product was extracted into diethyl ether (15 ml). After filtering, the solution was layered with hexanes and placed in a 238 K freezer. The product crystallized as orange-brown prisms.

Yield 0.118 g, 82%. 1H NMR (250 MHz, C6D6): 6.93 (d, JHH = 7.5 Hz, 1H, Ar-Hpara), 6.68 (t, JHH = 7.5 Hz, 2H, Ar-Hmeta), 2.80 (virtual t, 4H, JHP = 7.15 Hz,CH2), 1.25 (virtual t, 36H, J = 13.1 Hz C(CH3)3) p.p.m.. 13C{1H} (63 MHz, C6D6): 152.8 (t, 2JPC = 11.6 Hz, Ar-Cipso), 147.1 (virtual t, JCP= 32.3 Hz, Ar-Cortho), 125.8 (s, Ar-Cpara), 122.1 (virtual t, JCP = 15.8 Hz, Ar-Cpara), 34.5 (virtual t, JCP = 13.2 Hz, PCH2), 32.7 (virtual t, JCP = 24.6 Hz, PC(CH3)3), 29.6 (s, CH3) p.p.m.. 31P{1H} (101 MHz, C6D6): 69.5 (s) p.p.m..

Refinement top

Hydrogen atoms were included at geometrically idealized positions with C—H distances at the range of 0.93 - 0.98 Å and were treated as riding on their respective heavy atoms. The isotropic thermal parameters of the hydrogen atoms were fixed at 1.2 or 1.5 Ueq of the parent atom.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: APEX2 (Bruker, 2007); data reduction: APEX2 (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: publCIF (Westrip, 2008).

Figures top
[Figure 1] Fig. 1. View of the title compound showing full numbering scheme. Ellipsoids are shown at 50% probability and hydrogen atoms have been removed for clarity. Only one of the two symmetry equivalent positions for the nitrate group is shown.
[Figure 2] Fig. 2. Hydrogen bonding in (I). For clarity the tert-butyl substituents on P have been removed.
[2,6-Bis(di-tert-butylphosphinomethyl)phenyl- κ3P,C1,P'](nitrato-κO)nickel(II) top
Crystal data top
[Ni(C24H43P2)(NO3)]F(000) = 2208
Mr = 514.24Dx = 1.276 Mg m3
Orthorhombic, Fdd2Mo Kα radiation, λ = 0.71073 Å
Hall symbol: F 2 -2dCell parameters from 9535 reflections
a = 24.0023 (14) Åθ = 2.2–30.3°
b = 12.6350 (6) ŵ = 0.87 mm1
c = 17.6528 (6) ÅT = 225 K
V = 5353.5 (4) Å3Cut-prism, orange–brown
Z = 80.50 × 0.40 × 0.20 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
4078 independent reflections
Radiation source: fine-focus sealed tube3703 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.037
ϕ and ω scansθmax = 30.5°, θmin = 2.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
h = 3434
Tmin = 0.671, Tmax = 0.846k = 1818
33484 measured reflectionsl = 2525
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)] = 0.030H-atom parameters constrained
wR(F2) = 0.099 w = 1/[σ2(Fo2) + (0.1P)2 + 0.25P]
where P = (Fo2 + 2Fc2)/3
S = 0.81(Δ/σ)max = 0.001
4078 reflectionsΔρmax = 0.38 e Å3
156 parametersΔρmin = 0.38 e Å3
1 restraintAbsolute structure: Flack (1983), 1976 Freidel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.012 (10)
Crystal data top
[Ni(C24H43P2)(NO3)]V = 5353.5 (4) Å3
Mr = 514.24Z = 8
Orthorhombic, Fdd2Mo Kα radiation
a = 24.0023 (14) ŵ = 0.87 mm1
b = 12.6350 (6) ÅT = 225 K
c = 17.6528 (6) Å0.50 × 0.40 × 0.20 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
4078 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
3703 reflections with I > 2σ(I)
Tmin = 0.671, Tmax = 0.846Rint = 0.037
33484 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.030H-atom parameters constrained
wR(F2) = 0.099Δρmax = 0.38 e Å3
S = 0.81Δρmin = 0.38 e Å3
4078 reflectionsAbsolute structure: Flack (1983), 1976 Freidel pairs
156 parametersAbsolute structure parameter: 0.012 (10)
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*/UeqOcc. (<1)
Ni10.25000.25000.594610 (14)0.02536 (9)
P10.232841 (19)0.07823 (3)0.58242 (3)0.02639 (10)
C10.25000.25000.48634 (16)0.0263 (5)
C20.22870 (9)0.16438 (14)0.44415 (10)0.0293 (3)
C30.22918 (11)0.16401 (17)0.36544 (11)0.0381 (4)
H30.21530.10510.33900.046*
C40.25000.25000.32575 (19)0.0443 (8)
H40.25000.25000.27250.053*
C50.20438 (10)0.07210 (16)0.48626 (12)0.0357 (4)
H5A0.21490.00540.46180.043*
H5B0.16360.07700.48750.043*
C60.17578 (10)0.02125 (17)0.64252 (13)0.0356 (4)
C70.15103 (12)0.08133 (18)0.60934 (17)0.0492 (6)
H7A0.18030.13370.60380.074*
H7B0.13480.06650.56020.074*
H7C0.12250.10820.64310.074*
C80.13040 (11)0.1061 (2)0.64349 (17)0.0490 (5)
H8A0.10010.08330.67590.073*
H8B0.11660.11700.59250.073*
H8C0.14580.17180.66270.073*
C90.19464 (14)0.00157 (19)0.72359 (15)0.0484 (6)
H9A0.16230.00570.75610.073*
H9B0.21710.06070.74080.073*
H9C0.21660.06280.72560.073*
C100.29710 (10)0.00713 (16)0.58017 (16)0.0434 (5)
C110.33545 (12)0.0368 (3)0.5189 (2)0.0635 (9)
H11A0.36150.01760.50320.095*
H11B0.35580.09700.53880.095*
H11C0.31340.05900.47570.095*
C120.32896 (19)0.0019 (4)0.6540 (3)0.100 (2)
H12A0.32930.06630.67930.150*
H12B0.31100.05380.68640.150*
H12C0.36690.02400.64370.150*
C130.28517 (17)0.1214 (3)0.5629 (4)0.106 (2)
H13A0.27050.12740.51180.159*
H13B0.25800.14840.59860.159*
H13C0.31930.16210.56700.159*
N10.2619 (2)0.2312 (5)0.7546 (2)0.0478 (13)0.50
O10.22947 (16)0.2640 (3)0.70255 (19)0.0394 (7)0.50
O20.3061 (2)0.1884 (5)0.7355 (3)0.0732 (13)0.50
O30.25000.25000.8206 (2)0.0869 (14)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ni10.03377 (16)0.01934 (13)0.02296 (14)0.00129 (11)0.0000.000
P10.0305 (2)0.01967 (19)0.0290 (2)0.00015 (15)0.00072 (17)0.00082 (15)
C10.0312 (13)0.0241 (12)0.0238 (11)0.0033 (8)0.0000.000
C20.0344 (8)0.0280 (8)0.0256 (8)0.0006 (7)0.0019 (7)0.0025 (6)
C30.0478 (11)0.0397 (11)0.0267 (9)0.0013 (8)0.0025 (8)0.0070 (7)
C40.059 (2)0.0497 (19)0.0237 (12)0.0046 (13)0.0000.000
C50.0468 (11)0.0289 (9)0.0314 (9)0.0077 (8)0.0027 (8)0.0030 (7)
C60.0378 (10)0.0323 (8)0.0368 (10)0.0059 (8)0.0047 (8)0.0017 (7)
C70.0514 (13)0.0399 (11)0.0564 (14)0.0172 (10)0.0099 (11)0.0066 (9)
C80.0387 (11)0.0530 (13)0.0552 (14)0.0026 (10)0.0096 (10)0.0039 (11)
C90.0621 (16)0.0468 (14)0.0364 (11)0.0120 (11)0.0025 (10)0.0099 (9)
C100.0380 (10)0.0317 (10)0.0606 (15)0.0095 (7)0.0119 (10)0.0072 (9)
C110.0397 (12)0.0590 (16)0.092 (2)0.0147 (12)0.0217 (15)0.0184 (17)
C120.061 (2)0.168 (6)0.070 (3)0.056 (3)0.0012 (18)0.028 (2)
C130.069 (2)0.0339 (14)0.215 (7)0.0129 (13)0.034 (3)0.011 (2)
N10.057 (4)0.052 (4)0.0350 (19)0.016 (2)0.0114 (18)0.0079 (18)
O10.0488 (17)0.0462 (17)0.0233 (14)0.0022 (15)0.0012 (13)0.0048 (12)
O20.054 (2)0.104 (4)0.062 (3)0.012 (3)0.011 (2)0.019 (3)
O30.098 (3)0.137 (4)0.0265 (13)0.012 (2)0.0000.000
Geometric parameters (Å, º) top
Ni1—C11.911 (3)C7—H7C0.9700
Ni1—O1i1.976 (3)C8—H8A0.9700
Ni1—O11.976 (3)C8—H8B0.9700
Ni1—P1i2.2195 (4)C8—H8C0.9700
Ni1—P12.2195 (4)C9—H9A0.9700
P1—C51.831 (2)C9—H9B0.9700
P1—C61.876 (2)C9—H9C0.9700
P1—C101.882 (2)C10—C131.503 (4)
C1—C2i1.409 (2)C10—C121.516 (6)
C1—C21.409 (2)C10—C111.525 (4)
C2—C31.389 (3)C11—H11A0.9700
C2—C51.501 (3)C11—H11B0.9700
C3—C41.386 (3)C11—H11C0.9700
C3—H30.9400C12—H12A0.9700
C4—C3i1.386 (3)C12—H12B0.9700
C4—H40.9400C12—H12C0.9700
C5—H5A0.9800C13—H13A0.9700
C5—H5B0.9800C13—H13B0.9700
C6—C91.521 (3)C13—H13C0.9700
C6—C81.528 (4)N1—O31.223 (5)
C6—C71.541 (3)N1—O21.239 (7)
C7—H7A0.9700N1—O11.273 (5)
C7—H7B0.9700O3—N1i1.223 (5)
C1—Ni1—O1i164.64 (11)C6—C8—H8B109.5
C1—Ni1—O1164.64 (11)H8A—C8—H8B109.5
C1—Ni1—P1i84.437 (14)C6—C8—H8C109.5
O1i—Ni1—P1i97.74 (10)H8A—C8—H8C109.5
O1—Ni1—P1i93.00 (10)H8B—C8—H8C109.5
C1—Ni1—P184.435 (14)C6—C9—H9A109.5
O1i—Ni1—P193.00 (10)C6—C9—H9B109.5
O1—Ni1—P197.74 (10)H9A—C9—H9B109.5
P1i—Ni1—P1168.87 (3)C6—C9—H9C109.5
C5—P1—C6103.63 (10)H9A—C9—H9C109.5
C5—P1—C10105.18 (12)H9B—C9—H9C109.5
C6—P1—C10112.97 (10)C13—C10—C12110.1 (3)
C5—P1—Ni1101.56 (7)C13—C10—C11108.7 (3)
C6—P1—Ni1117.12 (7)C12—C10—C11106.1 (3)
C10—P1—Ni1114.22 (8)C13—C10—P1113.5 (2)
C2i—C1—C2116.2 (3)C12—C10—P1110.6 (2)
C2i—C1—Ni1121.90 (13)C11—C10—P1107.52 (16)
C2—C1—Ni1121.90 (13)C10—C11—H11A109.5
C3—C2—C1121.9 (2)C10—C11—H11B109.5
C3—C2—C5119.73 (18)H11A—C11—H11B109.5
C1—C2—C5118.39 (19)C10—C11—H11C109.5
C4—C3—C2120.4 (2)H11A—C11—H11C109.5
C4—C3—H3119.8H11B—C11—H11C109.5
C2—C3—H3119.8C10—C12—H12A109.5
C3i—C4—C3119.3 (3)C10—C12—H12B109.5
C3i—C4—H4120.4H12A—C12—H12B109.5
C3—C4—H4120.4C10—C12—H12C109.5
C2—C5—P1106.33 (13)H12A—C12—H12C109.5
C2—C5—H5A110.5H12B—C12—H12C109.5
P1—C5—H5A110.5C10—C13—H13A109.5
C2—C5—H5B110.5C10—C13—H13B109.5
P1—C5—H5B110.5H13A—C13—H13B109.5
H5A—C5—H5B108.7C10—C13—H13C109.5
C9—C6—C8108.4 (2)H13A—C13—H13C109.5
C9—C6—C7109.6 (2)H13B—C13—H13C109.5
C8—C6—C7108.6 (2)O1i—N1—O3165.1 (6)
C9—C6—P1112.18 (18)O1i—N1—O264.8 (4)
C8—C6—P1104.93 (15)O3—N1—O2123.0 (4)
C7—C6—P1112.90 (16)O3—N1—O1118.8 (4)
C6—C7—H7A109.5O2—N1—O1117.9 (5)
C6—C7—H7B109.5N1i—O1—O2i69.6 (4)
H7A—C7—H7B109.5O2i—O1—N1104.4 (4)
C6—C7—H7C109.5N1i—O1—Ni1152.8 (5)
H7A—C7—H7C109.5O2i—O1—Ni1133.8 (4)
H7B—C7—H7C109.5N1—O1—Ni1121.0 (3)
C6—C8—H8A109.5
Symmetry code: (i) x+1/2, y+1/2, z.

Experimental details

Crystal data
Chemical formula[Ni(C24H43P2)(NO3)]
Mr514.24
Crystal system, space groupOrthorhombic, Fdd2
Temperature (K)225
a, b, c (Å)24.0023 (14), 12.6350 (6), 17.6528 (6)
V3)5353.5 (4)
Z8
Radiation typeMo Kα
µ (mm1)0.87
Crystal size (mm)0.50 × 0.40 × 0.20
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2004)
Tmin, Tmax0.671, 0.846
No. of measured, independent and
observed [I > 2σ(I)] reflections
33484, 4078, 3703
Rint0.037
(sin θ/λ)max1)0.714
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.030, 0.099, 0.81
No. of reflections4078
No. of parameters156
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.38, 0.38
Absolute structureFlack (1983), 1976 Freidel pairs
Absolute structure parameter0.012 (10)

Computer programs: APEX2 (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999), publCIF (Westrip, 2008).

 

Acknowledgements

Funding was provided by the Natural Sciences and Engineering Research Council of Canada (NSERC PDF to DAD) and the Department of Energy (DE-FG02-06ER15765). The diffractometer was purchased via a National Science Foundation CRIF:MU award to the University of New Mexico (CHE-0443580). Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the US Department of Energy under contract No. DE-AC04-94AL85000.

References

First citationBoro, B. J., Dickie, D. A., Goldberg, K. I. & Kemp, R. A. (2008). Acta Cryst. E64, m1304.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationBrandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.  Google Scholar
First citationBruker (2004). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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