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Acta Cryst. (2008). E64, m455-m456    [ doi:10.1107/S1600536808003760 ]

Dichlorido(9-methyladenine-[kappa]N7)([eta]5-pentamethylcyclopentadienyl)iridium(III) dichloromethane solvate

C. Bruhn, T. Küger and D. Steinborn

Abstract top

In the title complex, [Ir(C10H15)Cl2(C6H7N5)]·CH2Cl2 or [Ir([eta]5-C5Me5)Cl2(9-MeAde-[kappa]N7)]·CH2Cl2 (9-MeAde = 9-methyladenine), the coordination geometry of the IrIII atom approximates to a three-legged piano stool. The 9-methyladenine ligand is coordinated in a monodentate fashion to the Ir centre through its N-7 atom. The crystal structure contains centrosymmetric pairs of molecules, interacting through two N-H...N hydrogen bonds. An intramolecular N-H...Cl hydrogen bond is formed between the H atom of an NH2 group and a chlorido ligand. Further short intra- and intermolecular C-H...Cl contacts are observed.

Comment top

Due to their importance in chemotherapy, nucleobase complexes of platinum and other transition metals attract attention. We are interested in syntheses and characterization of such complexes having, especially, metals in higher oxidation states (Zhu et al., 2002; Gaballa et al., 2004; Gaballa et al., 2007). The iridium(III) title complex [IrCl2(η5-C5Me5)(9-MeAde-κN7)].CH2Cl2 (see Figure 1) crystallizes in the triclinic space group P1. Crystals contain centrosymmetric dinuclear molecules (see Figure 2). The coordination geometry of the iridium center approximates a three-legged piano stool, the irdium atom being directly bound to two chloro ligands, to a N7 coordinated 9-methyladenine ligand and to a η5-pentamethylcyclopentadienyl ligand. The 9-MeAde ligand is planar in good approximation, the greatest deviation from the mean plane was found for the exocyclic N6 atom (0.06 (1) Å). The Ir–N7 and Ir–Cl1/Ir–Cl2 bonds are as long as those in the complex [IrCl2(η5-C5Me5)(NH2Ph-κN)] (2.152 (8) versus. 2.152 Å and 2.402 (3)/2.423 (3) versus. 2.394/2.419 Å) (Davies et al., 2003).

The dimers are formed through two N6–H6A···N1' hydrogen bonds (N6···N1' 3.01 (1) Å; H6A···N1' 2.14 Å; N6–H6A···N1' 170°). Furthermore, the other hydrogen atom of the exocyclic amino group acts as hydrogen donor in a N6–H6B···Cl2 hydrogen bond (N6···Cl2 3.17 (1) Å; H6B···Cl2 2.35 Å; N6–H6B···Cl2 155°). The structural parameters of these two hydrogen bonds are in accord with analogous hydrogen bonds in nucleobases and in chloro metal complexes, respectively (Jeffrey & Saenger, 1994; Baldovino-Pantaleon et al., 2007). Noteworthy, in crystals of 9-methyladenine two N6–H6A···N1' and N6–H6B···N7' hydrogen bonds link molecules in ribbons (Kistenmacher & Rossi, 1977; McMullan et al., 1980). Furthermore, short intra- and intermolecular C–H···Cl contacts (see Table) indicate stabilizing interactions (Huang et al., 1998; Aakeröy et al., 1999).

Related literature top

For background information, see: Lippert (2000); Houlton (2002). For related literature, see: Zhu et al. (2002); Gaballa et al. (2004); Aakeröy et al. (1999); Baldovino-Pantaleon, Morales-Morales, Hernandez-Ortega, Toscano & Valdes-Martinez (2007); Davies et al. (2003); Gaballa et al. (2007); Huang et al. (1998); Jeffrey & Saenger (1994); Kistenmacher & Rossi (1977); McMullan et al. (1980).

Experimental top

Reaction of [{IrCl2(η5-C5Me5)}2] with 9-methyladenine (9-MeAde) in 1: 2 ratio in methylene chloride resulted in the formation of yellow crystals of the title complex in 67% yield. 1H NMR (CD2Cl2, 200 MHz): δ 1.49 (s, 15H, C5(CH3)5), 3.88 (s, 3H, NCH3), 8.41 (s, br, 1H, H8), 8.64 (s, br, 1H, H2).

Refinement top

All non-H atoms were refined with anisotropic thermal parameters. H atoms were included in the model in calculated positions using the riding model, with their isotropic displacement parameter tied to 1.2 times that of the bonded atom.

Computing details top

Data collection: STADI4 (Stoe & Cie, 2002); cell refinement: STADI4 (Stoe & Cie, 2002); data reduction: X-RED (Stoe & Cie, 2002); 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: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Structure of the asymmetric unit of the title complex [IrCl2(η5-C5Me5)(9-MeAde-κN7)].CH2Cl2. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.
[Figure 2] Fig. 2. Structure of the dinuclear complex [{IrCl2(η5-C5Me5)(9-MeAde-κN7)}2] in crystals of the title compound. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii. The numbering scheme of the C atoms is as shown in Figure 1. Symmetry codes: (i) –x + 2, –y, –z + 2.
Dichlorido(9-methyladenine-κN7)(η5– pentamethylcyclopentadienyl)iridium(III) dichloromethane solvate top
Crystal data top
[Ir(C10H15)Cl2(C6H7N5)]·CH2Cl2Z = 2
Mr = 632.41F(000) = 612
Triclinic, P1Dx = 1.920 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.294 (2) ÅCell parameters from 32 reflections
b = 11.8698 (14) Åθ = 6.5–18.9°
c = 13.649 (3) ŵ = 6.60 mm−1
α = 71.338 (15)°T = 200 K
β = 83.83 (3)°Block, colourless
γ = 78.003 (14)°0.19 × 0.15 × 0.13 mm
V = 1094.0 (4) Å3
Data collection top
Stoe STADI-4
diffractometer		3246 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.068
graphiteθmax = 25.0°, θmin = 1.6°
profile data from ω/2θ scansh = −8→8
Absorption correction: multi-scan
(X-RED; Stoe & Cie, 2002)		k = −13→14
Tmin = 0.32, Tmax = 0.43l = −8→16
4132 measured reflections1 standard reflections every 60 min
3807 independent reflections intensity decay: none
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)] = 0.047Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.125H-atom parameters constrained
S = 1.13 w = 1/[σ2(Fo2) + (0.0666P)2]
where P = (Fo2 + 2Fc2)/3
3807 reflections(Δ/σ)max < 0.001
250 parametersΔρmax = 2.87 e Å−3
0 restraintsΔρmin = −3.41 e Å−3
0 constraints
Crystal data top
[Ir(C10H15)Cl2(C6H7N5)]·CH2Cl2γ = 78.003 (14)°
Mr = 632.41V = 1094.0 (4) Å3
Triclinic, P1Z = 2
a = 7.294 (2) ÅMo Kα radiation
b = 11.8698 (14) ŵ = 6.60 mm−1
c = 13.649 (3) ÅT = 200 K
α = 71.338 (15)°0.19 × 0.15 × 0.13 mm
β = 83.83 (3)°
Data collection top
Stoe STADI-4
diffractometer		3246 reflections with I > 2σ(I)
Absorption correction: multi-scan
(X-RED; Stoe & Cie, 2002)		Rint = 0.068
Tmin = 0.32, Tmax = 0.43θmax = 25.0°
4132 measured reflections1 standard reflections every 60 min
3807 independent reflections intensity decay: none
Refinement top
R[F2 > 2σ(F2)] = 0.047H-atom parameters constrained
wR(F2) = 0.125Δρmax = 2.87 e Å−3
S = 1.13Δρmin = −3.41 e Å−3
3807 reflectionsAbsolute structure: ?
250 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
C20.9961 (15)−0.0640 (10)0.7978 (9)0.030 (2)
H21.0628−0.14500.81650.036*
C40.8452 (14)0.0945 (9)0.6832 (8)0.023 (2)
C50.7931 (13)0.1571 (8)0.7549 (7)0.019 (2)
C60.8617 (15)0.0991 (9)0.8549 (8)0.026 (2)
C80.6814 (13)0.2726 (9)0.6092 (8)0.020 (2)
H80.61980.34020.55730.024*
C90.7869 (16)0.1435 (10)0.4929 (8)0.029 (2)
H9A0.71370.21090.44160.035*
H9B0.73750.06960.50340.035*
H9C0.91850.13180.46820.035*
C100.2376 (14)0.3257 (10)0.7454 (8)0.028 (2)
C110.3065 (16)0.2573 (10)0.8485 (9)0.030 (3)
C120.2955 (15)0.3417 (11)0.9036 (8)0.031 (3)
C130.2174 (16)0.4615 (11)0.8368 (10)0.037 (3)
C140.1805 (14)0.4482 (10)0.7419 (9)0.030 (3)
C150.213 (2)0.2713 (14)0.6624 (11)0.053 (4)
H15A0.24820.32420.59450.064*
H15B0.08210.26320.66350.064*
H15C0.29410.19140.67540.064*
C160.3688 (18)0.1234 (10)0.8885 (11)0.045 (3)
H16A0.47890.10480.93010.054*
H16B0.40140.09070.83010.054*
H16C0.26710.08690.93150.054*
C170.3513 (19)0.3108 (14)1.0118 (9)0.050 (4)
H17A0.40300.37721.01970.060*
H17B0.44650.23661.02820.060*
H17C0.24120.29821.05910.060*
C180.180 (2)0.5756 (12)0.8658 (13)0.060 (4)
H18A0.21260.64200.80670.072*
H18B0.25550.56510.92430.072*
H18C0.04640.59460.88550.072*
C190.0889 (17)0.5477 (13)0.6515 (12)0.056 (4)
H19A0.08300.62630.66210.068*
H19B−0.03830.53610.64620.068*
H19C0.16270.54540.58760.068*
C200.331 (2)0.2130 (12)0.3148 (10)0.045 (3)
H20A0.21670.21110.28260.053*
H20B0.35330.29720.29030.053*
Cl10.5584 (4)0.5480 (2)0.6167 (2)0.0268 (5)
Cl20.7133 (4)0.4366 (2)0.8520 (2)0.0289 (6)
Cl30.2938 (5)0.1691 (3)0.4491 (3)0.0505 (8)
Cl40.5213 (6)0.1194 (4)0.2750 (4)0.0745 (12)
N10.9631 (12)−0.0139 (8)0.8738 (7)0.027 (2)
N30.9494 (13)−0.0174 (7)0.6998 (7)0.029 (2)
N60.8322 (13)0.1512 (8)0.9311 (7)0.031 (2)
H6A0.87890.11150.99210.037*
H6B0.76630.22490.91990.037*
N70.6850 (11)0.2692 (7)0.7069 (6)0.0188 (17)
N90.7732 (12)0.1709 (8)0.5912 (6)0.0233 (18)
Ir0.47641 (5)0.39087 (3)0.76639 (3)0.01833 (15)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C20.030 (6)0.026 (6)0.033 (6)0.002 (5)−0.006 (5)−0.011 (5)
C40.025 (5)0.024 (5)0.026 (5)−0.008 (4)−0.003 (4)−0.011 (4)
C50.022 (5)0.017 (5)0.017 (5)−0.004 (4)0.001 (4)−0.006 (4)
C60.028 (6)0.023 (5)0.021 (5)0.002 (4)−0.003 (4)−0.003 (4)
C80.014 (5)0.017 (5)0.025 (5)0.002 (4)−0.004 (4)−0.004 (4)
C90.043 (7)0.025 (6)0.022 (5)−0.009 (5)0.006 (5)−0.011 (4)
C100.018 (5)0.040 (7)0.029 (6)−0.016 (5)0.005 (4)−0.011 (5)
C110.033 (6)0.025 (6)0.035 (6)−0.017 (5)0.016 (5)−0.009 (5)
C120.026 (6)0.043 (7)0.025 (6)−0.013 (5)0.010 (4)−0.012 (5)
C130.023 (6)0.030 (6)0.053 (8)0.005 (5)0.012 (5)−0.015 (6)
C140.018 (5)0.028 (6)0.037 (6)0.006 (4)−0.002 (4)−0.004 (5)
C150.055 (9)0.069 (10)0.053 (9)−0.046 (8)0.006 (7)−0.026 (8)
C160.048 (8)0.015 (6)0.064 (9)−0.014 (5)0.005 (6)0.001 (6)
C170.041 (7)0.074 (10)0.029 (7)−0.006 (7)0.006 (6)−0.013 (7)
C180.054 (9)0.041 (8)0.092 (12)0.003 (7)0.027 (8)−0.047 (8)
C190.019 (6)0.057 (9)0.068 (10)−0.001 (6)0.000 (6)0.012 (7)
C200.054 (8)0.037 (7)0.047 (8)−0.007 (6)−0.001 (6)−0.020 (6)
Cl10.0323 (14)0.0227 (13)0.0256 (13)−0.0081 (10)−0.0010 (10)−0.0057 (10)
Cl20.0349 (14)0.0274 (13)0.0295 (14)−0.0074 (11)−0.0051 (11)−0.0136 (11)
Cl30.055 (2)0.0467 (19)0.058 (2)−0.0206 (16)0.0060 (16)−0.0227 (16)
Cl40.071 (3)0.081 (3)0.072 (3)0.008 (2)0.009 (2)−0.042 (2)
N10.028 (5)0.018 (4)0.033 (5)0.000 (4)−0.002 (4)−0.008 (4)
N30.032 (5)0.015 (4)0.040 (6)0.001 (4)0.000 (4)−0.013 (4)
N60.043 (6)0.023 (5)0.023 (5)0.011 (4)−0.009 (4)−0.011 (4)
N70.021 (4)0.010 (4)0.020 (4)0.004 (3)−0.002 (3)−0.001 (3)
N90.029 (5)0.022 (4)0.019 (4)−0.006 (4)0.005 (3)−0.008 (4)
Ir0.0201 (2)0.0154 (2)0.0201 (2)−0.00199 (14)0.00201 (14)−0.00814 (15)
Geometric parameters (Å, °) top
C2—N31.325 (14)C13—C181.494 (17)
C2—N11.331 (14)C13—Ir2.159 (11)
C2—H20.9500C14—C191.510 (16)
C4—N31.348 (13)C14—Ir2.153 (10)
C4—N91.375 (13)C15—H15A0.9800
C4—C51.386 (14)C15—H15B0.9800
C5—N71.392 (12)C15—H15C0.9800
C5—C61.410 (14)C16—H16A0.9800
C6—N11.349 (13)C16—H16B0.9800
C6—N61.349 (14)C16—H16C0.9800
C8—N71.325 (13)C17—H17A0.9800
C8—N91.335 (13)C17—H17B0.9800
C8—H80.9500C17—H17C0.9800
C9—N91.467 (13)C18—H18A0.9800
C9—H9A0.9800C18—H18B0.9800
C9—H9B0.9800C18—H18C0.9800
C9—H9C0.9800C19—H19A0.9800
C10—C141.414 (16)C19—H19B0.9800
C10—C111.463 (16)C19—H19C0.9800
C10—C151.514 (17)C20—Cl41.743 (13)
C10—Ir2.127 (10)C20—Cl31.745 (13)
C11—C121.419 (16)C20—H20A0.9900
C11—C161.493 (15)C20—H20B0.9900
C11—Ir2.165 (10)Cl1—Ir2.402 (3)
C12—C131.458 (16)Cl2—Ir2.423 (3)
C12—C171.484 (16)N6—H6A0.8800
C12—Ir2.164 (10)N6—H6B0.8800
C13—C141.413 (17)N7—Ir2.152 (8)
N3—C2—N1129.5 (10)C12—C17—H17A109.5
N3—C2—H2115.3C12—C17—H17B109.5
N1—C2—H2115.3H17A—C17—H17B109.5
N3—C4—N9127.0 (9)C12—C17—H17C109.5
N3—C4—C5127.0 (10)H17A—C17—H17C109.5
N9—C4—C5106.0 (9)H17B—C17—H17C109.5
C4—C5—N7108.9 (8)C13—C18—H18A109.5
C4—C5—C6116.4 (9)C13—C18—H18B109.5
N7—C5—C6134.6 (9)H18A—C18—H18B109.5
N1—C6—N6119.0 (9)C13—C18—H18C109.5
N1—C6—C5117.6 (9)H18A—C18—H18C109.5
N6—C6—C5123.4 (9)H18B—C18—H18C109.5
N7—C8—N9112.9 (8)C14—C19—H19A109.5
N7—C8—H8123.5C14—C19—H19B109.5
N9—C8—H8123.5H19A—C19—H19B109.5
N9—C9—H9A109.5C14—C19—H19C109.5
N9—C9—H9B109.5H19A—C19—H19C109.5
H9A—C9—H9B109.5H19B—C19—H19C109.5
N9—C9—H9C109.5Cl4—C20—Cl3112.3 (8)
H9A—C9—H9C109.5Cl4—C20—H20A109.2
H9B—C9—H9C109.5Cl3—C20—H20A109.2
C14—C10—C11107.9 (10)Cl4—C20—H20B109.2
C14—C10—C15126.5 (11)Cl3—C20—H20B109.2
C11—C10—C15125.3 (11)H20A—C20—H20B107.9
C14—C10—Ir71.7 (6)C2—N1—C6119.0 (9)
C11—C10—Ir71.5 (6)C2—N3—C4110.4 (9)
C15—C10—Ir127.3 (8)C6—N6—H6A120.0
C12—C11—C10107.0 (10)C6—N6—H6B120.0
C12—C11—C16126.9 (11)H6A—N6—H6B120.0
C10—C11—C16126.1 (11)C8—N7—C5104.9 (8)
C12—C11—Ir70.8 (6)C8—N7—Ir119.3 (6)
C10—C11—Ir68.7 (5)C5—N7—Ir132.2 (6)
C16—C11—Ir127.4 (8)C8—N9—C4107.2 (8)
C11—C12—C13108.4 (10)C8—N9—C9126.4 (9)
C11—C12—C17125.0 (12)C4—N9—C9126.3 (9)
C13—C12—C17126.6 (12)C10—Ir—N797.3 (4)
C11—C12—Ir70.9 (6)C10—Ir—C1438.6 (4)
C13—C12—Ir70.1 (6)N7—Ir—C14130.7 (4)
C17—C12—Ir125.7 (8)C10—Ir—C1365.1 (5)
C14—C13—C12107.3 (10)N7—Ir—C13160.2 (4)
C14—C13—C18127.1 (12)C14—Ir—C1338.3 (5)
C12—C13—C18125.6 (13)C10—Ir—C1265.4 (4)
C14—C13—Ir70.6 (6)N7—Ir—C12126.5 (4)
C12—C13—Ir70.4 (6)C14—Ir—C1264.8 (4)
C18—C13—Ir125.4 (9)C13—Ir—C1239.4 (4)
C13—C14—C10109.4 (10)C10—Ir—C1139.9 (4)
C13—C14—C19125.8 (12)N7—Ir—C1195.5 (4)
C10—C14—C19124.7 (12)C14—Ir—C1165.2 (4)
C13—C14—Ir71.1 (6)C13—Ir—C1165.3 (4)
C10—C14—Ir69.7 (6)C12—Ir—C1138.3 (4)
C19—C14—Ir126.8 (8)C10—Ir—Cl1112.7 (3)
C10—C15—H15A109.5N7—Ir—Cl186.0 (2)
C10—C15—H15B109.5C14—Ir—Cl193.1 (3)
H15A—C15—H15B109.5C13—Ir—Cl1108.6 (3)
C10—C15—H15C109.5C12—Ir—Cl1147.4 (3)
H15A—C15—H15C109.5C11—Ir—Cl1152.5 (3)
H15B—C15—H15C109.5C10—Ir—Cl2160.2 (3)
C11—C16—H16A109.5N7—Ir—Cl291.0 (2)
C11—C16—H16B109.5C14—Ir—Cl2138.2 (3)
H16A—C16—H16B109.5C13—Ir—Cl2103.0 (4)
C11—C16—H16C109.5C12—Ir—Cl295.2 (3)
H16A—C16—H16C109.5C11—Ir—Cl2121.6 (3)
H16B—C16—H16C109.5Cl1—Ir—Cl285.72 (9)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N6—H6A···N1i0.882.143.007 (13)170.
N6—H6B···Cl20.882.353.168 (10)155.
C8—H8···Cl10.952.773.237 (11)111.
C8—H8···Cl1ii0.952.653.537 (11)156.
C9—H9B···Cl3iii0.982.753.697 (13)163.
C20—H20B···Cl1ii0.992.753.519 (15)135.
Symmetry codes: (i) −x+2, −y, −z+2; (ii) −x+1, −y+1, −z+1; (iii) −x+1, −y, −z+1.
Table 1
Selected geometric parameters (Å, °) top
C10—Ir2.127 (10)C14—Ir2.153 (10)
C11—Ir2.165 (10)Cl1—Ir2.402 (3)
C12—Ir2.164 (10)Cl2—Ir2.423 (3)
C13—Ir2.159 (11)N7—Ir2.152 (8)
N7—Ir—Cl186.0 (2)Cl1—Ir—Cl285.72 (9)
N7—Ir—Cl291.0 (2)
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N6—H6A···N1i0.882.143.007 (13)170.
N6—H6B···Cl20.882.353.168 (10)155.
C8—H8···Cl10.952.773.237 (11)111.
C8—H8···Cl1ii0.952.653.537 (11)156.
C9—H9B···Cl3iii0.982.753.697 (13)163.
C20—H20B···Cl1ii0.992.753.519 (15)135.
Symmetry codes: (i) −x+2, −y, −z+2; (ii) −x+1, −y+1, −z+1; (iii) −x+1, −y, −z+1.
Acknowledgements top

We thank the Deutsche Forschungsgemeinschaft for financial support.

references
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