supplementary materials


zj2095 scheme

Acta Cryst. (2012). E68, m1330-m1331    [ doi:10.1107/S1600536812040810 ]

trans-Dichloridobis[dicyclohexyl(2,4,6-trimethylphenyl)phosphane-[kappa]P]palladium(II)

I. Buthelezi, H. Chiririwa, H. Ogutu and R. Meijboom

Abstract top

The title compound, [PdCl2(C21H33P)2], forms a monomeric complex with a trans-square-planar coordination geometry about the PdII atom which lies on an inversion centre. The Pd-P bond lengths are 2.3760 (13) Å, while the Pd-Cl bond lengths are 2.3172 (14) Å. The observed structure was found to be closely related to that of trans-dichloridobis[dicyclohexyl(phenyl)phosphane-[kappa]P]palladium(II), [PdCl2{P(C6H11)2(C6H5)}2] [Burgoyne et al. (2012). Acta Cryst. E68, m404].

Comment top

Complexes involving palladium metal centres are amongst some of the most popular catalytic precursors in organic synthesis due to their catalytic abilities. They are used in carbon-carbon bond formation reactions like the Heck, Stille and Suzuki reactions (Bedford et al., 2004).[PdCl2(L)2] (L = tertiary phosphine, arsine or stibine) complexes can conveniently be prepared by the substitution of 1,5-cyclooctadiene (COD) from [PdCl2(COD)]. The title compound, trans-[PdCl2(C21H33P)2], crystallizes with the Pd atom on a center of symmetry and each pair of equivalent ligands in a mutually trans orientation.The geometry is,therefore, slightly distorted square planar and the Pd atom is not elevated out of the coordinating atom plane. All angles in the coordination polyhedron are close to the ideal value of 90°, with Cl2—Pd1—P1 = 88.39 (6)° and Cl2—Pd1—P1 = 91.61 (6)°. As required by the crystallographic symmetry, the Cl2—Pd1—Cl2 and P1—Pd1—P1 angles are 180°. The symmetry code used to define atoms through the inversion point is: 1 - x, -y, 1 - z.

The title compound compares well with other closely related PdII complexes from the literature containing two chloro and two tertiary phosphine ligands in a trans geometry (Muller & Meijboom, 2010a, b). The title compound, having a Pd1—Cl2 bond length of 2.3172 (14) Å and a Pd—P bond length of 2.3760 (13) Å, fits well into the typical range for complexes of this kind. Notably the title compound did not crystallize as a solvated complex; these type of PdII complexes have a tendency to crystallize as solvates (Ogutu & Meijboom, 2011).

Notably, the title compound is quintessentially isostructural with: [PdCl2{P(C6H11)3}2] (Grushin et al., 1994); [PdBr2{P(C6H11)3}2] (Clarke et al., 2003); and [PdCl2{P(C6H11)2(C7H7)}2] (Vuoti et al., 2008) ((C6H11) = cyclohexyl, (C7H7) = o-tolyl). The Pd–P and Pd–X (X = Br and Cl) bond lengths were compared and it was observed that they were all within the same range of 2.3–2.4 Å. The angles between the bonds around the Pd atom were all observed to be approximately right angles.

Related literature top

For a review on related compounds, see: Spessard & Miessler (1996). For the synthesis of the starting materials, see: Drew & Doyle (1990). For similar R—P2PdCl2 compounds, see: Ogutu & Meijboom (2011); Muller & Meijboom (2010a,b). For their applications, see: Bedford et al. (2004). For the closely related structure of trans-dichloridobis[dicyclohexyl(phenyl)phosphane-κP]palladium(II), see: Burgoyne et al. (2012). For isotypic structures, see: Clarke et al. (2003); Grushin et al. (1994); Vuoti et al. (2008).

Experimental top

Dicyclohexyl-(2,4,6 trimethyl phenyl)phosphine (0.11 g, 0.35 mmol) was dissolved in acetone (5cm3). A solution of [Pd(COD)Cl2] (0.05 g,0.17 mmol) in acetone (5 cm3) was added to the phosphine solution. The mixture was stirred for 5 minutes, after which the solution was left to crystallize. Yellow crystals of the title compound suitable for X-ray diffraction studies were obtained. 1H NMR (CDCl3, 400 MHz,p.p.m.): 6.9–6.8(m, 4H), 2.3 (m, 18H),1.5–1.4 (m, 16H),1.5 (m, 8H),1.6 (m, 16H),1.3 (m, 16H), 1.4 (m, 4H).31P NMR (CDCl3, 162.0 MHz, p.p.m.): 80.82. FTIR (cm-1):2920, 2850, 1713, 1678, 1597, 1553, 1442, 1337, 1074, 998, 883, 846, 728,

Refinement top

The aromatic, methine, and methyl H atoms were placed in geometrically idealized positions (C—H = 0.95–0.98) and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C) for aromatic and methine H atoms, and Uiso(H) = 1.5Ueq(C) for methyl H atoms respectively. Methyl torsion angles were refined from electron density.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT-Plus (Bruker, 2007); data reduction: SAINT-Plus (Bruker, 2007); 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 structure of the trans-Dichloridobis[dicyclohexyl-(2,4,6 trimethyl phenyl)phosphane-jP] palladium(II) showing 50% probability displacement ellipsoids. Symmetry code to generate molecule through inversiont point: 1 - x, -y, 1 - z.
[Figure 2] Fig. 2. A perspective of trans-Dichloridobis[dicyclohexyl-(2,4,6 trimethyl phenyl)phosphane-jP] palladium(II) showing the molecular packing modes in the crystals.
(I) top
Crystal data top
C42H66Cl2P2PdZ = 1
Mr = 810.19F(000) = 428
Triclinic, P1Dx = 1.332 Mg m3
Dm = 1.332 Mg m3
Dm measured by not measured
Hall symbol: -P 1Mo Kα radiation, λ = 0.71069 Å
a = 9.466 (5) ÅCell parameters from 3294 reflections
b = 10.625 (5) Åθ = 2.2–28.3°
c = 11.527 (5) ŵ = 0.70 mm1
α = 63.932 (5)°T = 100 K
β = 84.500 (5)°Cube, yellow
γ = 75.874 (5)°0.22 × 0.17 × 0.16 mm
V = 1009.8 (8) Å3
Data collection top
Bruker APEXII CCD
diffractometer
3385 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.082
φ and ω scansθmax = 28.3°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
h = 1212
Tmin = 0.861, Tmax = 0.896k = 1414
17391 measured reflectionsl = 1515
4932 independent reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.061Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.165H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0919P)2]
where P = (Fo2 + 2Fc2)/3
4932 reflections(Δ/σ)max < 0.001
217 parametersΔρmax = 1.05 e Å3
0 restraintsΔρmin = 1.93 e Å3
Crystal data top
C42H66Cl2P2Pdγ = 75.874 (5)°
Mr = 810.19V = 1009.8 (8) Å3
Triclinic, P1Z = 1
a = 9.466 (5) ÅMo Kα radiation
b = 10.625 (5) ŵ = 0.70 mm1
c = 11.527 (5) ÅT = 100 K
α = 63.932 (5)°0.22 × 0.17 × 0.16 mm
β = 84.500 (5)°
Data collection top
Bruker APEXII CCD
diffractometer
4932 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
3385 reflections with I > 2σ(I)
Tmin = 0.861, Tmax = 0.896Rint = 0.082
17391 measured reflectionsθmax = 28.3°
Refinement top
R[F2 > 2σ(F2)] = 0.061H-atom parameters constrained
wR(F2) = 0.165Δρmax = 1.05 e Å3
S = 1.02Δρmin = 1.93 e Å3
4932 reflectionsAbsolute structure: ?
217 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

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.

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 > 2sigma(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
Pd10.500.50.02770 (17)
Cl20.66664 (12)0.13206 (13)0.48974 (13)0.0403 (3)
P10.31238 (11)0.14874 (12)0.56557 (10)0.0279 (3)
C160.3797 (5)0.2560 (5)0.6307 (4)0.0332 (10)
C110.1511 (6)0.2214 (6)0.3425 (5)0.0420 (12)
H11A0.08170.16590.40010.05*
H11B0.22850.15490.31970.05*
C60.0268 (5)0.1246 (5)0.6872 (5)0.0363 (11)
C20.2357 (5)0.0711 (5)0.7937 (5)0.0358 (11)
C10.1790 (5)0.0641 (5)0.6878 (4)0.0316 (10)
H10.16090.01370.63690.038*
C40.0041 (6)0.0812 (6)0.8892 (5)0.0438 (12)
C210.4639 (5)0.1621 (6)0.7596 (5)0.0405 (12)
H21A0.39760.11230.82650.049*
H21B0.54380.08810.74920.049*
C170.2603 (5)0.3749 (5)0.6446 (5)0.0415 (12)
H17A0.20870.43730.56080.05*
H17B0.18850.33140.70890.05*
C150.3216 (5)0.3781 (6)0.3220 (5)0.0435 (12)
H15A0.35870.42530.36630.052*
H15B0.4060.31520.30180.052*
C30.1420 (6)0.1368 (5)0.8900 (5)0.0427 (12)
H30.18220.22550.96040.051*
C120.0713 (6)0.3418 (6)0.2195 (5)0.0501 (14)
H12A0.0280.29890.17470.06*
H12B0.0090.40510.24340.06*
C70.3943 (6)0.1527 (6)0.8096 (5)0.0491 (14)
H7A0.43140.1730.8940.074*
H7B0.45210.09430.74110.074*
H7C0.40140.24340.80390.074*
C100.2180 (5)0.2864 (5)0.4122 (4)0.0300 (9)
H100.13690.35210.43430.036*
C180.3265 (6)0.4651 (6)0.6878 (7)0.0567 (16)
H18A0.39390.51290.62080.068*
H18B0.2480.54080.69710.068*
C200.5269 (6)0.2537 (7)0.8028 (6)0.0527 (14)
H20A0.59960.29650.73930.063*
H20B0.57740.19170.88710.063*
C90.0548 (5)0.2671 (6)0.5890 (5)0.0477 (13)
H9A0.1550.28820.61770.071*
H9B0.0560.26330.50570.071*
H9C0.00640.34280.57960.071*
C130.1717 (7)0.4301 (6)0.1292 (5)0.0555 (15)
H13A0.11590.50870.05270.067*
H13B0.24750.36890.09910.067*
C50.0587 (5)0.0501 (6)0.7852 (5)0.0449 (13)
H50.16040.09060.78160.054*
C190.4088 (6)0.3735 (7)0.8154 (6)0.0565 (15)
H19A0.34050.33130.88440.068*
H19B0.45370.4340.83920.068*
C140.2432 (6)0.4931 (6)0.1962 (5)0.0517 (14)
H14A0.16810.5640.21570.062*
H14B0.31440.54460.13730.062*
C80.1042 (7)0.1536 (7)0.9946 (6)0.0652 (18)
H8A0.06150.2571.0380.098*
H8B0.1990.13780.95690.098*
H8C0.11710.11291.05750.098*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Pd10.0255 (3)0.0175 (3)0.0286 (3)0.00253 (18)0.00010 (18)0.00339 (19)
Cl20.0323 (6)0.0314 (6)0.0560 (8)0.0062 (5)0.0050 (5)0.0190 (6)
P10.0264 (6)0.0194 (6)0.0277 (6)0.0018 (4)0.0007 (4)0.0043 (5)
C160.034 (2)0.027 (2)0.034 (2)0.0008 (19)0.0038 (19)0.011 (2)
C110.042 (3)0.035 (3)0.041 (3)0.001 (2)0.007 (2)0.013 (2)
C60.032 (2)0.032 (3)0.042 (3)0.002 (2)0.003 (2)0.017 (2)
C20.037 (2)0.026 (2)0.034 (2)0.0014 (19)0.0014 (19)0.007 (2)
C10.036 (2)0.021 (2)0.029 (2)0.0017 (18)0.0018 (18)0.0067 (18)
C40.051 (3)0.038 (3)0.046 (3)0.021 (2)0.016 (2)0.019 (2)
C210.038 (3)0.037 (3)0.035 (3)0.002 (2)0.004 (2)0.009 (2)
C170.035 (2)0.032 (3)0.054 (3)0.001 (2)0.002 (2)0.020 (2)
C150.042 (3)0.035 (3)0.031 (2)0.003 (2)0.003 (2)0.004 (2)
C30.055 (3)0.030 (3)0.030 (2)0.007 (2)0.008 (2)0.005 (2)
C120.051 (3)0.049 (3)0.044 (3)0.004 (3)0.016 (2)0.014 (3)
C70.049 (3)0.030 (3)0.040 (3)0.013 (2)0.005 (2)0.002 (2)
C100.027 (2)0.024 (2)0.027 (2)0.0038 (17)0.0026 (17)0.0049 (18)
C180.046 (3)0.044 (3)0.088 (5)0.003 (3)0.004 (3)0.040 (3)
C200.045 (3)0.061 (4)0.051 (3)0.001 (3)0.008 (3)0.028 (3)
C90.029 (2)0.045 (3)0.047 (3)0.006 (2)0.003 (2)0.009 (3)
C130.065 (4)0.048 (3)0.035 (3)0.002 (3)0.013 (3)0.006 (3)
C50.029 (2)0.047 (3)0.057 (3)0.008 (2)0.008 (2)0.023 (3)
C190.052 (3)0.069 (4)0.065 (4)0.016 (3)0.015 (3)0.045 (4)
C140.051 (3)0.039 (3)0.038 (3)0.006 (3)0.012 (2)0.007 (2)
C80.075 (4)0.056 (4)0.062 (4)0.024 (3)0.032 (3)0.024 (3)
Geometric parameters (Å, º) top
Pd1—Cl22.3172 (14)C15—H15A0.99
Pd1—Cl2i2.3172 (14)C15—H15B0.99
Pd1—P12.3760 (13)C3—H30.95
Pd1—P1i2.3760 (13)C12—C131.502 (8)
P1—C101.859 (4)C12—H12A0.99
P1—C161.862 (5)C12—H12B0.99
P1—C11.868 (5)C7—H7A0.98
C16—C171.532 (6)C7—H7B0.98
C16—C211.541 (6)C7—H7C0.98
C11—C101.524 (7)C10—H101
C11—C121.536 (7)C18—C191.520 (9)
C11—H11A0.99C18—H18A0.99
C11—H11B0.99C18—H18B0.99
C6—C51.382 (7)C20—C191.526 (8)
C6—C11.427 (6)C20—H20A0.99
C6—C91.503 (7)C20—H20B0.99
C2—C31.393 (6)C9—H9A0.98
C2—C11.431 (6)C9—H9B0.98
C2—C71.522 (6)C9—H9C0.98
C1—H11C13—C141.509 (8)
C4—C31.364 (7)C13—H13A0.99
C4—C51.395 (8)C13—H13B0.99
C4—C81.510 (7)C5—H50.95
C21—C201.522 (8)C19—H19A0.99
C21—H21A0.99C19—H19B0.99
C21—H21B0.99C14—H14A0.99
C17—C181.526 (7)C14—H14B0.99
C17—H17A0.99C8—H8A0.98
C17—H17B0.99C8—H8B0.98
C15—C141.534 (6)C8—H8C0.98
C15—C101.540 (6)
Cl2—Pd1—Cl2i180C13—C12—H12B109.2
Cl2—Pd1—P191.61 (6)C11—C12—H12B109.2
Cl2i—Pd1—P188.39 (6)H12A—C12—H12B107.9
Cl2—Pd1—P1i88.39 (6)C2—C7—H7A109.5
Cl2i—Pd1—P1i91.61 (6)C2—C7—H7B109.5
P1—Pd1—P1i180H7A—C7—H7B109.5
C10—P1—C16103.8 (2)C2—C7—H7C109.5
C10—P1—C1110.9 (2)H7A—C7—H7C109.5
C16—P1—C1104.3 (2)H7B—C7—H7C109.5
C10—P1—Pd1104.11 (15)C11—C10—C15110.4 (4)
C16—P1—Pd1114.10 (15)C11—C10—P1112.8 (3)
C1—P1—Pd1118.79 (15)C15—C10—P1110.9 (3)
C17—C16—C21109.7 (4)C11—C10—H10107.5
C17—C16—P1113.7 (3)C15—C10—H10107.5
C21—C16—P1112.9 (3)P1—C10—H10107.5
C10—C11—C12109.6 (4)C19—C18—C17111.6 (5)
C10—C11—H11A109.7C19—C18—H18A109.3
C12—C11—H11A109.7C17—C18—H18A109.3
C10—C11—H11B109.7C19—C18—H18B109.3
C12—C11—H11B109.7C17—C18—H18B109.3
H11A—C11—H11B108.2H18A—C18—H18B108
C5—C6—C1119.4 (4)C21—C20—C19111.7 (5)
C5—C6—C9114.2 (4)C21—C20—H20A109.3
C1—C6—C9126.4 (4)C19—C20—H20A109.3
C3—C2—C1119.4 (4)C21—C20—H20B109.3
C3—C2—C7115.9 (4)C19—C20—H20B109.3
C1—C2—C7124.7 (4)H20A—C20—H20B107.9
C6—C1—C2117.3 (4)C6—C9—H9A109.5
C6—C1—P1125.7 (3)C6—C9—H9B109.5
C2—C1—P1116.9 (3)H9A—C9—H9B109.5
C6—C1—H190.7C6—C9—H9C109.5
C2—C1—H190.7H9A—C9—H9C109.5
P1—C1—H190.7H9B—C9—H9C109.5
C3—C4—C5116.5 (4)C12—C13—C14110.5 (5)
C3—C4—C8123.1 (5)C12—C13—H13A109.6
C5—C4—C8120.4 (5)C14—C13—H13A109.6
C20—C21—C16110.7 (4)C12—C13—H13B109.6
C20—C21—H21A109.5C14—C13—H13B109.6
C16—C21—H21A109.5H13A—C13—H13B108.1
C20—C21—H21B109.5C6—C5—C4123.7 (5)
C16—C21—H21B109.5C6—C5—H5118.2
H21A—C21—H21B108.1C4—C5—H5118.2
C18—C17—C16110.3 (4)C18—C19—C20109.5 (5)
C18—C17—H17A109.6C18—C19—H19A109.8
C16—C17—H17A109.6C20—C19—H19A109.8
C18—C17—H17B109.6C18—C19—H19B109.8
C16—C17—H17B109.6C20—C19—H19B109.8
H17A—C17—H17B108.1H19A—C19—H19B108.2
C14—C15—C10110.9 (4)C13—C14—C15112.5 (5)
C14—C15—H15A109.4C13—C14—H14A109.1
C10—C15—H15A109.4C15—C14—H14A109.1
C14—C15—H15B109.4C13—C14—H14B109.1
C10—C15—H15B109.4C15—C14—H14B109.1
H15A—C15—H15B108H14A—C14—H14B107.8
C4—C3—C2123.7 (5)C4—C8—H8A109.5
C4—C3—H3118.1C4—C8—H8B109.5
C2—C3—H3118.1H8A—C8—H8B109.5
C13—C12—C11111.8 (5)C4—C8—H8C109.5
C13—C12—H12A109.2H8A—C8—H8C109.5
C11—C12—H12A109.2H8B—C8—H8C109.5
Symmetry code: (i) x+1, y, z+1.
Acknowledgements top

Financial assistance from the South African National Research Foundation (SA NRF), the Research Fund of the University of Johannesburg, TESP and SASOL is gratefully acknowledged.

references
References top

Bedford, R. B., Cazin, C. S. J. & Holder, D. (2004). Coord. Chem. Rev. 248, 2283–2321.

Bruker (2007). APEX2 and SAINT-Plus. Bruker AXS Inc., Madison, Wisconsin, USA.

Burgoyne, A. R., Meijboom, R. & Ogutu, H. (2012). Acta Cryst. E68, m404.

Clarke, M. L., Orpen, A. G., Pringle, P. G. & Turley, E. (2003). Dalton Trans. pp. 4393–4394.

Drew, D. & Doyle, J. R. (1990). Inorg. Synth. 28, 346–349.

Grushin, V. V., Bensimon, C. & Alper, H. (1994). Inorg. Chem. 33, 4804–4806.

Muller, A. & Meijboom, R. (2010a). Acta Cryst. E66, m1420.

Muller, A. & Meijboom, R. (2010b). Acta Cryst. E66, m1463.

Ogutu, H. & Meijboom, R. (2011). Acta Cryst. E67, m1662.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.

Spessard, G. O. & Miessler, G. L. (1996). Organometallic Chemistry, pp. 131–135 Upper Saddle River, New Jersey: Prentice Hall.

Vuoti, S., Autio, J., Laitila, M., Haukka, M. & Pursiainen, J. (2008). Eur. J. Inorg. Chem. pp. 397–407.