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Acta Cryst. (2008). E64, m454    [ doi:10.1107/S1600536808000603 ]

A second polymorph of [1,2-bis(di-tert-butylphosphino)ethane]dichloridoplatinum(II)

A. Gunay, W. W. Brennessel and W. D. Jones

Abstract top

The title complex, [PtCl2(C18H40P2)], contains a PtII center in an approximately square-planar geometry [cis angle range = 88.09 (3)-91.39 (3)°; twist angle = 1.19 (5)°]. The Pt-P bond lengths of 2.2536 (8) and 2.2513 (8) Å and the Pt-Cl bond lengths of 2.3750 (8) and 2.3588 (8) Å are normal. This crystal form is a polymorph of a structure reported previously [Harada, Kai, Yasuoka & Kasai (1976). Bull. Chem. Soc. Jpn, 49, 3472-3477].

Comment top

One of the most commonly used Pt(0) precursors, Pt(COD)2, COD = 1,5-cyclooctadiene, is generally synthesized by the reduction of platinumdichlorides, like Pt(COD)Cl2, with Li2(COT), COT = cyclooctatetraene (Green et al., 1977; Crascall & Spencer, 1990), or with SmI2 (Ogoshi et al., 2004). The latter reduction with 20 equivalents of SmI2 afforded Pt(COD)2 in moderate yields (45% average). After addition of chelating ligand 1,2-bis(di-tert-butylphosphino)ethane (dtbpe) to the SmI2 reduction product, it was observed that some PtII remained, based on the formation of the title compound, Pt(dtbpe)Cl2 (I). An independent synthesis of (I) was performed to support these observations, in which dtbpe was added directly to Pt(COD)Cl2 (see experimental section). The resulting pure product in 88% yield was characterized by 1H, 13C, 31P NMR spectroscopies and by single-crystal X-ray diffraction.

Related literature top

For related literature, see: Crascall & Spencer (1990); Green et al. (1977); McDermott et al. (1976); Ogoshi et al. (2004).

Experimental top

Pt(COD)Cl2, COD = 1,5-cyclooctadiene, was synthesized according to the published procedure (McDermott et al., 1976). Under an atmosphere of dinitrogen, bis(di-tert-butylphosphino)ethane (dtbpe) (212 mg, 0.67 mmol) was added to a light yellow suspension of Pt(COD)Cl2 (250 mg, 0.67 mmol) in THF (25 ml). The reaction mixture was heated with stirring for 12 h at 373 K. After complete conversion to (I) was verified by 31P NMR spectroscopy, the volatiles (THF, COD) were removed in vacuo, leaving the white powdery product (343.4 mg, 0.59 mmol) in 88% yield. Crystals of (I) were grown by vapor diffusion of hexanes into THF.

Refinement top

The H-atoms were included in the refinements at geometrically idealized positions with C—H distances 0.98 and 0.99 Å for CH3 and CH2 type H-atoms, respectively; Uiso values were 1.5Ueq and 1.2Ueq of the carrier atoms for the methyl and CH2 groups, respectively. The final difference map showed a residual electron density in the vicinity of H31A atom and was chemically meaningless.

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Bruker, 2000); software used to prepare material for publication: SHELXTL (Bruker, 2000).

Figures top
[Figure 1] Fig. 1. Displacement ellipsoid (50% probability) drawing of (I) with H atoms omitted.
[1,2-bis(di-tert-butylphosphino)ethane]dichloridoplatinum(II) top
Crystal data top
[PtCl2(C18H40P2)]F000 = 1160
Mr = 584.43Dx = 1.663 Mg m−3
Monoclinic, P21/nMo Kα radiation
λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 4040 reflections
a = 11.0981 (10) Åθ = 3.0–32.9º
b = 15.3242 (13) ŵ = 6.38 mm−1
c = 14.5413 (13) ÅT = 100.0 (1) K
β = 109.287 (1)ºBlock, colorless
V = 2334.2 (4) Å30.20 × 0.14 × 0.08 mm
Z = 4
Data collection top
Bruker SMART APEXII CCD
diffractometer		8022 independent reflections
Radiation source: fine-focus sealed tube6312 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.034
T = 100.0(1) Kθmax = 32.0º
area detector, ω scans per φθmin = 2.0º
Absorption correction: multi-scan
(SADABS; Sheldrick, 2007)		h = −15→16
Tmin = 0.342, Tmax = 0.600k = −22→22
20415 measured reflectionsl = −19→21
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)] = 0.029H-atom parameters constrained
wR(F2) = 0.060  w = 1/[σ2(Fo2) + (0.0232P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max = 0.002
8022 reflectionsΔρmax = 1.11 e Å−3
208 parametersΔρmin = −0.81 e Å−3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
[PtCl2(C18H40P2)]V = 2334.2 (4) Å3
Mr = 584.43Z = 4
Monoclinic, P21/nMo Kα
a = 11.0981 (10) ŵ = 6.38 mm−1
b = 15.3242 (13) ÅT = 100.0 (1) K
c = 14.5413 (13) Å0.20 × 0.14 × 0.08 mm
β = 109.287 (1)º
Data collection top
Bruker SMART APEXII CCD
diffractometer		8022 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2007)		6312 reflections with I > 2σ(I)
Tmin = 0.342, Tmax = 0.600Rint = 0.034
20415 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.029208 parameters
wR(F2) = 0.060H-atom parameters constrained
S = 1.02Δρmax = 1.11 e Å−3
8022 reflectionsΔρmin = −0.81 e Å−3
Special details top

Experimental. 1H NMR (CDCl3, 20 °C): δ 1.5 (d, 3JHP = 14.1 Hz, 36 H, -(CH3)3), 1.9 (d, 2JHP = 16 Hz, 4 H, -CH2-); 13C NMR (CDCl3, 20 °C): δ 24.5 (d, 1JCP = 33 Hz, -CH2-), 30.4 (s, -(CH3)3), 37.6 (d, 1JCP = 30 Hz, -C-); 31P NMR (CDCl3, 20 °C): δ 75.7 (s, with platinum satellites 1JPPt = 3643.2 Hz).

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
Pt10.268368 (10)0.706474 (7)0.781256 (8)0.01505 (3)
Cl10.17379 (7)0.80168 (5)0.86681 (6)0.02422 (16)
Cl20.44219 (8)0.80401 (5)0.81687 (6)0.02415 (16)
P10.09956 (7)0.61552 (5)0.74524 (5)0.01603 (14)
P20.36188 (7)0.61746 (5)0.70173 (6)0.01776 (15)
C10.0577 (3)0.5718 (2)0.8529 (2)0.0227 (6)
C2−0.0053 (4)0.4814 (2)0.8323 (3)0.0323 (8)
H2A−0.02530.46130.88960.048*
H2B0.05330.44000.81770.048*
H2C−0.08420.48510.77630.048*
C3−0.0326 (3)0.6333 (2)0.8823 (3)0.0287 (7)
H3A−0.05200.60850.93800.043*
H3B−0.11200.64020.82730.043*
H3C0.00830.69030.90020.043*
C40.1821 (3)0.5634 (2)0.9392 (2)0.0308 (8)
H4A0.16320.54090.99600.046*
H4B0.22270.62080.95470.046*
H4C0.24000.52310.92210.046*
C5−0.0478 (3)0.6578 (2)0.6491 (2)0.0232 (7)
C6−0.1592 (3)0.5927 (2)0.6247 (3)0.0302 (8)
H6A−0.23340.61770.57440.045*
H6B−0.18120.58070.68340.045*
H6C−0.13420.53830.60060.045*
C7−0.0919 (3)0.7459 (2)0.6749 (3)0.0316 (8)
H7A−0.16860.76450.62240.047*
H7B−0.02400.78910.68330.047*
H7C−0.11130.74060.73570.047*
C8−0.0127 (3)0.6711 (3)0.5569 (3)0.0388 (9)
H8A−0.08710.69320.50460.058*
H8B0.01430.61540.53700.058*
H8C0.05730.71330.57000.058*
C90.5007 (3)0.5527 (2)0.7849 (2)0.0246 (7)
C100.5670 (4)0.4957 (2)0.7285 (3)0.0349 (9)
H10A0.63770.46370.77470.052*
H10B0.59990.53290.68740.052*
H10C0.50530.45410.68740.052*
C110.5985 (3)0.6126 (2)0.8564 (3)0.0340 (8)
H11A0.66900.57740.89840.051*
H11B0.55730.64400.89670.051*
H11C0.63170.65460.81990.051*
C120.4469 (3)0.4907 (2)0.8451 (3)0.0298 (8)
H12A0.51660.45610.88900.045*
H12B0.38400.45160.80110.045*
H12C0.40580.52490.88340.045*
C130.4076 (3)0.6704 (2)0.5996 (2)0.0241 (7)
C140.5394 (3)0.7143 (2)0.6356 (3)0.0292 (7)
H14A0.55790.74040.58020.044*
H14B0.60460.67070.66670.044*
H14C0.53960.76000.68290.044*
C150.4083 (4)0.6035 (2)0.5199 (3)0.0374 (9)
H15A0.43220.63290.46870.056*
H15B0.32300.57800.49190.056*
H15C0.47020.55720.54890.056*
C160.3071 (3)0.7402 (2)0.5518 (3)0.0286 (7)
H16A0.32860.76840.49880.043*
H16B0.30550.78390.60060.043*
H16C0.22290.71260.52560.043*
C310.1465 (3)0.5180 (2)0.6924 (2)0.0216 (6)
H31A0.18530.47550.74520.026*
H31B0.06900.49080.64650.026*
C320.2411 (3)0.5363 (2)0.6385 (2)0.0211 (6)
H32A0.19380.55770.57210.025*
H32B0.28420.48130.63200.025*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Pt10.01739 (5)0.01316 (5)0.01369 (5)0.00118 (5)0.00389 (4)−0.00008 (4)
Cl10.0232 (4)0.0226 (4)0.0254 (4)0.0034 (3)0.0061 (3)−0.0079 (3)
Cl20.0275 (4)0.0195 (4)0.0271 (4)−0.0052 (3)0.0112 (3)−0.0035 (3)
P10.0182 (4)0.0177 (4)0.0132 (3)−0.0006 (3)0.0066 (3)−0.0002 (3)
P20.0202 (4)0.0158 (4)0.0199 (4)−0.0004 (3)0.0102 (3)−0.0011 (3)
C10.0277 (16)0.0264 (16)0.0185 (15)0.0043 (13)0.0137 (13)0.0043 (12)
C20.046 (2)0.0275 (18)0.0333 (19)−0.0032 (16)0.0261 (17)0.0057 (15)
C30.0365 (19)0.0297 (18)0.0269 (17)0.0024 (15)0.0201 (15)0.0022 (14)
C40.0348 (19)0.041 (2)0.0186 (16)0.0045 (16)0.0116 (14)0.0099 (15)
C50.0185 (15)0.0330 (18)0.0165 (15)−0.0029 (13)0.0034 (12)0.0040 (13)
C60.0208 (16)0.037 (2)0.0302 (19)−0.0070 (14)0.0053 (14)−0.0058 (15)
C70.0222 (17)0.0323 (19)0.034 (2)0.0028 (14)0.0009 (15)0.0085 (16)
C80.0208 (17)0.071 (3)0.0212 (18)−0.0038 (17)0.0018 (14)0.0117 (18)
C90.0239 (16)0.0186 (15)0.0326 (18)0.0045 (12)0.0109 (14)0.0015 (13)
C100.0326 (19)0.0228 (17)0.056 (2)0.0042 (15)0.0233 (18)−0.0002 (16)
C110.0236 (17)0.0309 (18)0.041 (2)0.0022 (15)0.0021 (15)0.0048 (16)
C120.0287 (18)0.0263 (17)0.036 (2)0.0079 (14)0.0126 (15)0.0104 (15)
C130.0296 (17)0.0250 (16)0.0238 (17)−0.0025 (14)0.0172 (14)−0.0011 (13)
C140.0272 (17)0.0292 (18)0.0363 (19)0.0001 (14)0.0173 (15)0.0008 (15)
C150.050 (2)0.042 (2)0.0306 (19)−0.0120 (19)0.0282 (18)−0.0071 (17)
C160.0315 (18)0.0327 (18)0.0255 (18)−0.0035 (15)0.0148 (15)0.0084 (14)
C310.0270 (16)0.0180 (15)0.0243 (16)−0.0022 (12)0.0144 (13)−0.0048 (12)
C320.0244 (15)0.0202 (15)0.0221 (15)−0.0033 (12)0.0125 (12)−0.0046 (12)
Geometric parameters (Å, °) top
Pt1—P22.2513 (8)C8—H8B0.9800
Pt1—P12.2536 (8)C8—H8C0.9800
Pt1—Cl22.3588 (8)C9—C111.535 (5)
Pt1—Cl12.3750 (8)C9—C101.542 (5)
P1—C311.833 (3)C9—C121.540 (5)
P1—C51.881 (3)C10—H10A0.9800
P1—C11.897 (3)C10—H10B0.9800
P2—C321.837 (3)C10—H10C0.9800
P2—C91.895 (3)C11—H11A0.9800
P2—C131.903 (3)C11—H11B0.9800
C1—C41.534 (5)C11—H11C0.9800
C1—C31.535 (4)C12—H12A0.9800
C1—C21.537 (5)C12—H12B0.9800
C2—H2A0.9800C12—H12C0.9800
C2—H2B0.9800C13—C161.536 (5)
C2—H2C0.9800C13—C141.536 (5)
C3—H3A0.9800C13—C151.549 (5)
C3—H3B0.9800C14—H14A0.9800
C3—H3C0.9800C14—H14B0.9800
C4—H4A0.9800C14—H14C0.9800
C4—H4B0.9800C15—H15A0.9800
C4—H4C0.9800C15—H15B0.9800
C5—C71.525 (5)C15—H15C0.9800
C5—C81.528 (5)C16—H16A0.9800
C5—C61.536 (4)C16—H16B0.9800
C6—H6A0.9800C16—H16C0.9800
C6—H6B0.9800C31—C321.529 (4)
C6—H6C0.9800C31—H31A0.9900
C7—H7A0.9800C31—H31B0.9900
C7—H7B0.9800C32—H32A0.9900
C7—H7C0.9800C32—H32B0.9900
C8—H8A0.9800
P2—Pt1—P189.70 (3)C5—C8—H8C109.5
P2—Pt1—Cl290.82 (3)H8A—C8—H8C109.5
P1—Pt1—Cl2178.77 (3)H8B—C8—H8C109.5
P2—Pt1—Cl1178.84 (3)C11—C9—C10110.2 (3)
P1—Pt1—Cl191.39 (3)C11—C9—C12107.7 (3)
Cl2—Pt1—Cl188.09 (3)C10—C9—C12107.1 (3)
C31—P1—C5105.46 (15)C11—C9—P2111.3 (2)
C31—P1—C1103.85 (14)C10—C9—P2112.8 (2)
C5—P1—C1110.23 (14)C12—C9—P2107.4 (2)
C31—P1—Pt1105.77 (10)C9—C10—H10A109.5
C5—P1—Pt1114.31 (11)C9—C10—H10B109.5
C1—P1—Pt1115.98 (11)H10A—C10—H10B109.5
C32—P2—C9105.70 (15)C9—C10—H10C109.5
C32—P2—C13103.69 (14)H10A—C10—H10C109.5
C9—P2—C13110.56 (15)H10B—C10—H10C109.5
C32—P2—Pt1106.44 (10)C9—C11—H11A109.5
C9—P2—Pt1113.88 (11)C9—C11—H11B109.5
C13—P2—Pt1115.45 (11)H11A—C11—H11B109.5
C4—C1—C3108.6 (3)C9—C11—H11C109.5
C4—C1—C2108.2 (3)H11A—C11—H11C109.5
C3—C1—C2108.1 (3)H11B—C11—H11C109.5
C4—C1—P1107.8 (2)C9—C12—H12A109.5
C3—C1—P1111.9 (2)C9—C12—H12B109.5
C2—C1—P1112.1 (2)H12A—C12—H12B109.5
C1—C2—H2A109.5C9—C12—H12C109.5
C1—C2—H2B109.5H12A—C12—H12C109.5
H2A—C2—H2B109.5H12B—C12—H12C109.5
C1—C2—H2C109.5C16—C13—C14108.5 (3)
H2A—C2—H2C109.5C16—C13—C15107.8 (3)
H2B—C2—H2C109.5C14—C13—C15107.8 (3)
C1—C3—H3A109.5C16—C13—P2107.9 (2)
C1—C3—H3B109.5C14—C13—P2113.0 (2)
H3A—C3—H3B109.5C15—C13—P2111.7 (2)
C1—C3—H3C109.5C13—C14—H14A109.5
H3A—C3—H3C109.5C13—C14—H14B109.5
H3B—C3—H3C109.5H14A—C14—H14B109.5
C1—C4—H4A109.5C13—C14—H14C109.5
C1—C4—H4B109.5H14A—C14—H14C109.5
H4A—C4—H4B109.5H14B—C14—H14C109.5
C1—C4—H4C109.5C13—C15—H15A109.5
H4A—C4—H4C109.5C13—C15—H15B109.5
H4B—C4—H4C109.5H15A—C15—H15B109.5
C7—C5—C8107.0 (3)C13—C15—H15C109.5
C7—C5—C6109.4 (3)H15A—C15—H15C109.5
C8—C5—C6107.7 (3)H15B—C15—H15C109.5
C7—C5—P1113.1 (2)C13—C16—H16A109.5
C8—C5—P1106.7 (2)C13—C16—H16B109.5
C6—C5—P1112.6 (2)H16A—C16—H16B109.5
C5—C6—H6A109.5C13—C16—H16C109.5
C5—C6—H6B109.5H16A—C16—H16C109.5
H6A—C6—H6B109.5H16B—C16—H16C109.5
C5—C6—H6C109.5C32—C31—P1113.8 (2)
H6A—C6—H6C109.5C32—C31—H31A108.8
H6B—C6—H6C109.5P1—C31—H31A108.8
C5—C7—H7A109.5C32—C31—H31B108.8
C5—C7—H7B109.5P1—C31—H31B108.8
H7A—C7—H7B109.5H31A—C31—H31B107.7
C5—C7—H7C109.5C31—C32—P2112.3 (2)
H7A—C7—H7C109.5C31—C32—H32A109.2
H7B—C7—H7C109.5P2—C32—H32A109.2
C5—C8—H8A109.5C31—C32—H32B109.2
C5—C8—H8B109.5P2—C32—H32B109.2
H8A—C8—H8B109.5H32A—C32—H32B107.9
P2—Pt1—P1—C318.74 (11)C1—P1—C5—C6−48.9 (3)
Cl1—Pt1—P1—C31−170.88 (11)Pt1—P1—C5—C6178.4 (2)
P2—Pt1—P1—C5−106.82 (12)C32—P2—C9—C11−169.3 (2)
Cl1—Pt1—P1—C573.55 (12)C13—P2—C9—C1179.1 (3)
P2—Pt1—P1—C1123.22 (11)Pt1—P2—C9—C11−52.8 (3)
Cl1—Pt1—P1—C1−56.40 (11)C32—P2—C9—C1066.3 (3)
P1—Pt1—P2—C329.20 (11)C13—P2—C9—C10−45.3 (3)
Cl2—Pt1—P2—C32−169.68 (11)Pt1—P2—C9—C10−177.3 (2)
P1—Pt1—P2—C9−106.85 (12)C32—P2—C9—C12−51.6 (2)
Cl2—Pt1—P2—C974.27 (12)C13—P2—C9—C12−163.2 (2)
P1—Pt1—P2—C13123.65 (12)Pt1—P2—C9—C1264.9 (2)
Cl2—Pt1—P2—C13−55.24 (12)C32—P2—C13—C1681.9 (2)
C31—P1—C1—C483.6 (2)C9—P2—C13—C16−165.2 (2)
C5—P1—C1—C4−163.8 (2)Pt1—P2—C13—C16−34.1 (3)
Pt1—P1—C1—C4−31.9 (3)C32—P2—C13—C14−158.1 (2)
C31—P1—C1—C3−157.1 (2)C9—P2—C13—C14−45.2 (3)
C5—P1—C1—C3−44.5 (3)Pt1—P2—C13—C1485.9 (2)
Pt1—P1—C1—C387.4 (2)C32—P2—C13—C15−36.4 (3)
C31—P1—C1—C2−35.4 (3)C9—P2—C13—C1576.5 (3)
C5—P1—C1—C277.2 (3)Pt1—P2—C13—C15−152.4 (2)
Pt1—P1—C1—C2−151.0 (2)C5—P1—C31—C3291.5 (2)
C31—P1—C5—C7−172.7 (2)C1—P1—C31—C32−152.5 (2)
C1—P1—C5—C775.7 (3)Pt1—P1—C31—C32−30.0 (2)
Pt1—P1—C5—C7−57.0 (3)P1—C31—C32—P239.6 (3)
C31—P1—C5—C8−55.3 (3)C9—P2—C32—C3191.6 (2)
C1—P1—C5—C8−166.8 (2)C13—P2—C32—C31−152.0 (2)
Pt1—P1—C5—C860.4 (3)Pt1—P2—C32—C31−29.8 (2)
C31—P1—C5—C662.6 (3)
Table 1
Selected geometric parameters (Å, °) top
Pt1—P22.2513 (8)Pt1—Cl22.3588 (8)
Pt1—P12.2536 (8)Pt1—Cl12.3750 (8)
P2—Pt1—P189.70 (3)P2—Pt1—Cl1178.84 (3)
P2—Pt1—Cl290.82 (3)P1—Pt1—Cl191.39 (3)
P1—Pt1—Cl2178.77 (3)Cl2—Pt1—Cl188.09 (3)
Acknowledgements top

We thank the US Department of Energy for support (grant FG02–86ER13569).

references
References top

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