[(1,2,5,6-η)-1,3,5,7-Cyclo­octa­tetra­ene]iodido(meth­yl)platinum(II)

In the title complex, [Pt(CH₃)I(C₈H₈)], the Pt^II centre lies in a square-planar environment defined by the I and methyl C atoms and the mid-points of the two π-coordinated double bonds of 1,3,5,7-cyclo­octa­tetra­ene. Because of the different trans influences of the I atom and the methyl group, the Pt—C bonds trans to the methyl group are longer than those trans to the I atom.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.014 Å
• R factor = 0.035
• wR factor = 0.095
• Data-to-parameter ratio = 20.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT153_ALERT_1_C The su's on the Cell Axes   are Equal (x 100000)        200 Ang.
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Pt     -   I       ..       6.18 su
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         Pt
PLAT342_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...         14

Alert level G
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K
PLAT794_ALERT_5_G Check Predicted Bond Valency for Pt          (2)       1.66

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   5 ALERT level C = Check and explain
   3 ALERT level G = General alerts; check

   4 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

In the title complex, [PtI(CH₃)(C₈H₈)], the central Pt^II ion lies in an essentially square-planar environment defined by the I and methyl C atoms and by the two midpoints (M1, M2) of the π-coordinated double bonds of the 1,3,5,7-cyclooctatetraene (cot) ligand (M1 and M2 denote the midpoints of the olefinic bonds C1—C2 and C5—C6, respectively). The Pt, I, C9 atoms and the midpoints lie in a coordination plane with the largest deviation of 0.024 Å (M2) from the least-squares plane, and with bond angles in the range 85.9–94.5°.

Owing to the different trans influence of the I atom and methyl group, the Pt—C bondstrans to C9 are on average 0.142 Å longer than those trans to I (mean lengths: Pt—C1/C2 = 2.280 Å, Pt—C5/C6 = 2.138 Å). The distances between the Pt atom and the midpoints are 2.174 Å (M1) and 2.019 Å (M2). The cot ligand coordinates symmetrically to the Pt atom in the "tub" conformation, and displays some increase in the coordinated double-bond distances (1.376 (12) Å and 1.401 (13) Å) compared to the non-coordinated double bonds (1.325 (13) Å and 1.289 (15) Å). The four coordinating C atoms (C1, C2, C5 and C6) and the four non-coordinating C atoms (C3, C4, C7 and C8) lie on respective planes, with the torsion angles C1—C2—C5—C6 = 0.8 (7)° and C3—C4—C7—C8 = -1.6 (8)°. The Pt atom is displaced by 1.532 (5) Å from the plane C1/C2/C5/C6, and by 2.501 (5) Å from the plane C3/C4/C7/C8. The dihedral angle between these least-squares planes is 0.4 (7)°. In the complex, the cot ring angles lie in the range 121.2 (8)–123.7 (8)°.

Related literature

For a related structure, see: Song et al. (2006).

S2. Experimental

An aqueous solution of HI (57%; 0.1337 g, 0.596 mmol) was added to a solution of cyclooctatetraenedimethylplatinum(II) (0.2120 g, 0.644 mmol) in CH₂Cl₂ (20 ml) and MeOH (10 ml), and stirred for 10 h at room temperature. The solvent was removed under vacuum, the residue was washed with pentane, dissolved in ether, and filtered through a plug of Al₂O₃ (1 cm × 2 cm). Evaporation of the solvent gave a yellow powder (0.0171 g). Crystals suitable for X-ray analysis were obtained by slow evaporation from a CH₂Cl₂ solution.

S3. Refinement

H atoms were positioned geometrically and allowed to ride on their respective carrier atoms, with C—H = 0.98, 0.93 or 0.96 Å and with U_iso(H) = 1.2U_eq(C) or 1.5U_eq(methyl C).

Computing details

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. The structure of the title compound, with displacement ellipsoids drawn at the 30% probability level for non-H atoms.
	Fig. 2. View of the unit-cell contents of the title compound.

[(1,2,5,6-η⁴)-1,3,5,7-Cyclooctatetraene]iodo(methyl)platinum(II)

Crystal data

[Pt(CH3)I(C8H8)]	F(000) = 784
Mr = 441.17	Dx = 2.941 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3200 reflections
a = 8.447 (2) Å	θ = 2.7–26.4°
b = 10.181 (2) Å	µ = 17.12 mm^−1
c = 13.504 (2) Å	T = 293 K
β = 120.901 (3)°	Plate, yellow
V = 996.5 (3) Å^3	0.18 × 0.17 × 0.10 mm
Z = 4

Data collection

Bruker SMART 1000 CCD diffractometer	2034 independent reflections
Radiation source: fine-focus sealed tube	1824 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.031
φ and ω scans	θmax = 26.4°, θmin = 2.7°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −5→10
Tmin = 0.063, Tmax = 0.181	k = −12→12
5241 measured reflections	l = −16→14

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.095	H-atom parameters constrained
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0652P)^2 + 0.318P] where P = (Fo^2 + 2Fc^2)/3
2034 reflections	(Δ/σ)max < 0.001
101 parameters	Δρmax = 2.04 e Å^−3
0 restraints	Δρmin = −1.65 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Pt	−0.07706 (4)	0.19134 (3)	0.33127 (2)	0.03353 (14)
I	−0.25885 (8)	0.36453 (6)	0.37576 (6)	0.0554 (2)
C1	0.1744 (12)	0.1904 (9)	0.5146 (7)	0.048 (2)
H1	0.1547	0.2215	0.5761	0.058*
C2	0.2011 (11)	0.2851 (9)	0.4519 (8)	0.0438 (19)
H2	0.1965	0.3760	0.4743	0.053*
C3	0.3096 (11)	0.2642 (9)	0.3965 (7)	0.0456 (19)
H3	0.4196	0.3097	0.4233	0.055*
C4	0.2537 (12)	0.1815 (9)	0.3090 (8)	0.050 (2)
H4	0.3263	0.1694	0.2763	0.060*
C5	0.0784 (12)	0.1079 (9)	0.2621 (7)	0.048 (2)
H5	0.0101	0.0950	0.1783	0.057*
C6	0.0489 (13)	0.0121 (8)	0.3254 (8)	0.052 (2)
H6	−0.0371	−0.0580	0.2793	0.063*
C7	0.1911 (14)	−0.0256 (10)	0.4420 (10)	0.061 (2)
H7	0.2403	−0.1099	0.4550	0.073*
C8	0.2505 (14)	0.0547 (11)	0.5277 (9)	0.066 (3)
H8	0.3438	0.0272	0.6002	0.079*
C9	−0.3222 (14)	0.1393 (12)	0.1861 (8)	0.064 (3)
H9A	−0.3010	0.0683	0.1476	0.096*
H9B	−0.3711	0.2133	0.1350	0.096*
H9C	−0.4088	0.1122	0.2080	0.096*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Pt	0.0312 (2)	0.0354 (2)	0.0346 (2)	−0.00195 (10)	0.01736 (15)	−0.00058 (11)
I	0.0558 (4)	0.0487 (4)	0.0810 (4)	0.0069 (3)	0.0489 (3)	0.0041 (3)
C1	0.036 (4)	0.074 (7)	0.029 (4)	−0.008 (4)	0.013 (3)	−0.005 (4)
C2	0.037 (4)	0.051 (5)	0.045 (4)	−0.009 (3)	0.022 (4)	−0.015 (4)
C3	0.027 (4)	0.050 (5)	0.052 (5)	−0.003 (4)	0.015 (3)	0.010 (4)
C4	0.045 (5)	0.062 (6)	0.057 (5)	0.014 (4)	0.036 (4)	0.016 (4)
C5	0.052 (5)	0.052 (5)	0.048 (4)	0.004 (4)	0.032 (4)	−0.007 (4)
C6	0.063 (6)	0.028 (4)	0.067 (6)	−0.003 (4)	0.034 (5)	−0.007 (4)
C7	0.064 (6)	0.041 (5)	0.082 (7)	0.012 (4)	0.041 (5)	0.020 (5)
C8	0.053 (6)	0.076 (7)	0.062 (6)	0.013 (5)	0.025 (5)	0.041 (6)
C9	0.048 (5)	0.081 (7)	0.046 (5)	−0.014 (5)	0.012 (4)	−0.009 (5)

Geometric parameters (Å, º)

Pt—C9	2.060 (9)	C4—C5	1.481 (13)
Pt—C6	2.135 (8)	C4—H4	0.930
Pt—C5	2.140 (8)	C5—C6	1.401 (13)
Pt—C2	2.270 (8)	C5—H5	0.980
Pt—C1	2.289 (8)	C6—C7	1.459 (14)
Pt—I	2.6029 (7)	C6—H6	0.980
C1—C2	1.376 (12)	C7—C8	1.289 (15)
C1—C8	1.495 (14)	C7—H7	0.930
C1—H1	0.980	C8—H8	0.930
C2—C3	1.466 (12)	C9—H9A	0.960
C2—H2	0.980	C9—H9B	0.960
C3—C4	1.325 (13)	C9—H9C	0.960
C3—H3	0.930
C9—Pt—C6	91.2 (4)	C2—C3—H3	119.4
C9—Pt—C5	91.4 (4)	C3—C4—C5	121.6 (8)
C6—Pt—C5	38.3 (3)	C3—C4—H4	119.2
C9—Pt—C2	162.8 (4)	C5—C4—H4	119.2
C6—Pt—C2	92.0 (3)	C6—C5—C4	122.9 (8)
C5—Pt—C2	80.8 (3)	C6—C5—Pt	70.7 (5)
C9—Pt—C1	161.7 (4)	C4—C5—Pt	108.4 (6)
C6—Pt—C1	80.4 (3)	C6—C5—H5	115.4
C5—Pt—C1	91.9 (3)	C4—C5—H5	115.4
C2—Pt—C1	35.1 (3)	Pt—C5—H5	115.4
C9—Pt—I	88.3 (3)	C5—C6—C7	122.4 (8)
C6—Pt—I	162.2 (3)	C5—C6—Pt	71.1 (5)
C5—Pt—I	159.5 (2)	C7—C6—Pt	109.5 (7)
C2—Pt—I	93.7 (2)	C5—C6—H6	115.2
C1—Pt—I	94.8 (2)	C7—C6—H6	115.2
C2—C1—C8	121.6 (8)	Pt—C6—H6	115.2
C2—C1—Pt	71.7 (5)	C8—C7—C6	121.8 (9)
C8—C1—Pt	103.6 (6)	C8—C7—H7	119.1
C2—C1—H1	116.6	C6—C7—H7	119.1
C8—C1—H1	116.6	C7—C8—C1	122.3 (9)
Pt—C1—H1	116.6	C7—C8—H8	118.8
C1—C2—C3	123.7 (8)	C1—C8—H8	118.8
C1—C2—Pt	73.2 (5)	Pt—C9—H9A	109.5
C3—C2—Pt	105.1 (5)	Pt—C9—H9B	109.5
C1—C2—H2	115.3	H9A—C9—H9B	109.5
C3—C2—H2	115.3	Pt—C9—H9C	109.5
Pt—C2—H2	115.3	H9A—C9—H9C	109.5
C4—C3—C2	121.2 (8)	H9B—C9—H9C	109.5
C4—C3—H3	119.4
C9—Pt—C1—C2	171.3 (12)	I—Pt—C5—C6	−179.1 (5)
C6—Pt—C1—C2	107.5 (6)	C9—Pt—C5—C4	150.5 (7)
C5—Pt—C1—C2	70.9 (6)	C6—Pt—C5—C4	−119.3 (8)
I—Pt—C1—C2	−89.7 (5)	C2—Pt—C5—C4	−14.1 (6)
C9—Pt—C1—C8	52.1 (15)	C1—Pt—C5—C4	−47.6 (6)
C6—Pt—C1—C8	−11.7 (6)	I—Pt—C5—C4	61.6 (10)
C5—Pt—C1—C8	−48.3 (6)	C4—C5—C6—C7	−1.8 (14)
C2—Pt—C1—C8	−119.2 (9)	Pt—C5—C6—C7	−101.6 (9)
I—Pt—C1—C8	151.1 (6)	C4—C5—C6—Pt	99.8 (8)
C8—C1—C2—C3	−2.2 (13)	C9—Pt—C6—C5	90.7 (6)
Pt—C1—C2—C3	−97.2 (8)	C2—Pt—C6—C5	−72.4 (5)
C8—C1—C2—Pt	95.0 (8)	C1—Pt—C6—C5	−105.7 (6)
C9—Pt—C2—C1	−170.8 (13)	I—Pt—C6—C5	178.9 (6)
C6—Pt—C2—C1	−70.2 (6)	C9—Pt—C6—C7	−150.6 (7)
C5—Pt—C2—C1	−106.9 (6)	C5—Pt—C6—C7	118.7 (9)
I—Pt—C2—C1	93.0 (5)	C2—Pt—C6—C7	46.3 (7)
C9—Pt—C2—C3	−49.5 (16)	C1—Pt—C6—C7	13.0 (6)
C6—Pt—C2—C3	51.1 (6)	I—Pt—C6—C7	−62.4 (11)
C5—Pt—C2—C3	14.3 (6)	C5—C6—C7—C8	66.5 (14)
C1—Pt—C2—C3	121.2 (9)	Pt—C6—C7—C8	−13.0 (12)
I—Pt—C2—C3	−145.8 (6)	C6—C7—C8—C1	1.9 (16)
C1—C2—C3—C4	66.9 (12)	C2—C1—C8—C7	−67.4 (13)
Pt—C2—C3—C4	−12.8 (10)	Pt—C1—C8—C7	9.3 (12)
C2—C3—C4—C5	0.9 (13)	C1—C2—C5—C6	0.8 (7)
C3—C4—C5—C6	−65.9 (12)	C3—C4—C7—C8	−1.6 (8)
C3—C4—C5—Pt	12.6 (10)	C3—C2—C1—C8	−2.2 (13)
C9—Pt—C5—C6	−90.2 (6)	C4—C5—C6—C7	−1.8 (14)
C2—Pt—C5—C6	105.2 (6)	C2—C3—C4—C5	0.9 (13)
C1—Pt—C5—C6	71.8 (5)	C6—C7—C8—C1	1.9 (16)