trans-Dichlorido­bis(3,4-dimethyl­pyridine)platinum(II)

Abstract

In the title compound, trans-[PtCl₂(C₇H₉N)₂], the Pt^II atom is located on an inversion center and is coordinated by two 3,4-dimethyl­pyridine ligands and two chloride ligands, resulting in a typical slightly distorted square-planar geometry. The crystallographic inversion centre forces the value of the C—N—N—C torsion angle to be linear and the 3,4-dimethyl-pyridine ligands to be coplanar.

Related literature

For related complexes see: Tessier & Rochon (1999 ▶); Eremenko et al. (1997 ▶); Shaver et al. (2000 ▶); Zordan et al. (2005 ▶); Rochon et al. (1996 ▶); Colamarino & Orioli (1975 ▶). For the geometry of the pyridine ligand, see: Bond & Davies (2002 ▶). For related literature, see: Orpen et al. (1989 ▶).

Experimental

Crystal data

• [PtCl₂(C₇H₉N)₂]

• M _r = 480.29

• Monoclinic,

• a = 7.9763 (5) Å

• b = 7.1102 (3) Å

• c = 13.3586 (7) Å

• β = 98.247 (5)°

• V = 749.77 (7) ų

• Z = 2

• Mo Kα radiation

• μ = 9.70 mm⁻¹

• T = 120 (2) K

• 0.21 × 0.20 × 0.10 mm

Data collection

• Nonius KappaCCD diffractometer

• Absorption correction: multi-scan (SADABS; Sheldrick, 2003 ▶) T _min = 0.201, T _max = 0.381

• 17165 measured reflections

• 2177 independent reflections

• 1705 reflections with I > 2σ(I)

• R _int = 0.033

Refinement

• R[F ² > 2σ(F ²)] = 0.015

• wR(F ²) = 0.030

• S = 1.08

• 2177 reflections

• 90 parameters

• H-atom parameters constrained

• Δρ_max = 0.67 e Å⁻³

• Δρ_min = −0.78 e Å⁻³

Data collection: COLLECT (Bruker–Nonius, 2004 ▶); cell refinement: EVALCCD (Duisenberg et al., 2003 ▶); data reduction: EVALCCD; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: DIAMOND (Brandenburg, 2006 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Selected geometric parameters (Å, °).

Pt1—N1	2.0148 (18)
Pt1—Cl1	2.2901 (6)

N1—Pt1—Cl1

89.85 (6)

supplementary crystallographic information

Comment

The complex trans-[PtCl₂(C₇H₉N)₂] has an inversion symmetry and the Pt^II atom is situated at an inversion center and it is coordinated by two 3,4-dimethylpyridine ligands and two chloro ligands and exhibit trans configuration. Such arrangement of ligands leads to the square planar geometry. In the coordination polyhedron, all angles are very close to the ideal value of 90°. The crystallographic inversion centre forces the value of the torsion angle C1—N1—N1ⁱ—Cⁱ (symmetry operation i: -x, -y, -z) to be 180° and the the 3,4-dimethyl-pyridine ligands to be coplanar.

The geometry of 3,4-dimethylpyridine ligands resembles the geometry of the uncoordinated 3,4-dimethylpyridine, i.e. the C—C and C—N bond distances and angles in the coordinated 3,4-dimethylpyridine agree well with the expected value (Bond, Davies, 2002). The bond distance Pt–N (2.0148 (18) Å) is similar to the Pt—N bond lengths in other related compounds (Orpen et al., 1989). The Pt—Cl bond lengths agree well with the reported values (See Table 2).

All trans-[PtCl₂L₂] complexes given in Table 2 have the same coordination environment as in the title compound. Indeed, they are square-planar and their pyridine rings lie in the same plane. The N—Pt—N and Cl—Pt—Cl angles in all observed compounds are equal to 180°, the angles N—Pt—Cl are very close to 90°.

Experimental

3,4-dimethylpyridine (1 ml) was added to the powder of K₂[PtCl₄] (0.2 g) and the resulting mixture was heated to 150°C until the complete evaporation of the 3,4-dimethylpyridine. The resulting complex was recrystallized from CHCl₃ (yield 92%). Crystals were obtained by slow evaporation of CHCl₃ solution. Anal. calc. for C₁₄H₁₈N₂Cl₂Pt:C, 35.01; H, 3.78; N, 5.83%. Found: C, 35.30; H, 3.96; N, 5.54%.

Refinement

Hydrogen atoms were positioned geometrically and constrained to ride on their parent atoms, with C—H = 0.95–0.98 Å, and Uĩso~ = 1.2–1.5 U~eq~(parent atom). The highest peak is located 0.87 Å from atom Pt1 and the deepest hole is located 0.83 Å from atom Pt1.

Figures

Fig. 1.

The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.

Crystal data

[PtCl2(C7H9N)2]	F(000) = 456
Mr = 480.29	Dx = 2.127 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2339 reflections
a = 7.9763 (5) Å	θ = 1.0–20.0°
b = 7.1102 (3) Å	µ = 9.70 mm−1
c = 13.3586 (7) Å	T = 120 K
β = 98.247 (5)°	Block, pale yellow
V = 749.77 (7) Å3	0.21 × 0.20 × 0.10 mm
Z = 2

Data collection

Nonius KappaCCD diffractometer	2177 independent reflections
Radiation source: fine-focus sealed tube	1705 reflections with I > 2σ(I)
horizontally mounted graphite crystal	Rint = 0.033
Detector resolution: 9 pixels mm-1 pixels mm-1	θmax = 30.0°, θmin = 2.8°
φ scans and ω scans with κ offset	h = −11→10
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	k = −10→9
Tmin = 0.201, Tmax = 0.381	l = −18→18
17165 measured reflections

Refinement

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.015	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.030	H-atom parameters constrained
S = 1.08	w = 1/[σ2(Fo2) + (0.0064P)2 + 0.7739P] where P = (Fo2 + 2Fc2)/3
2177 reflections	(Δ/σ)max < 0.001
90 parameters	Δρmax = 0.67 e Å−3
0 restraints	Δρmin = −0.78 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
Pt1	0.0000	0.0000	0.0000	0.01078 (3)
Cl1	−0.12594 (8)	−0.27477 (8)	0.03883 (4)	0.01897 (11)
N1	0.0259 (2)	0.0765 (3)	0.14663 (13)	0.0127 (4)
C1	−0.0247 (3)	0.2464 (3)	0.17546 (16)	0.0143 (4)
H1	−0.0716	0.3324	0.1246	0.017*
C2	−0.0115 (3)	0.3015 (3)	0.27567 (16)	0.0141 (4)
C3	−0.0729 (3)	0.4918 (3)	0.30137 (17)	0.0227 (5)
H3A	−0.1179	0.5582	0.2390	0.034*
H3B	0.0215	0.5637	0.3379	0.034*
H3C	−0.1623	0.4781	0.3440	0.034*
C4	0.0634 (3)	0.1776 (3)	0.35029 (16)	0.0138 (4)
C5	0.0883 (3)	0.2318 (4)	0.45953 (16)	0.0188 (5)
H5A	0.1668	0.3383	0.4702	0.028*
H5B	0.1353	0.1249	0.5006	0.028*
H5C	−0.0209	0.2676	0.4795	0.028*
C6	0.1162 (3)	0.0044 (4)	0.31969 (15)	0.0161 (4)
H6	0.1677	−0.0824	0.3688	0.019*
C7	0.0948 (3)	−0.0435 (3)	0.21858 (17)	0.0163 (5)
H7	0.1297	−0.1645	0.1994	0.020*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Pt1	0.01278 (5)	0.01094 (5)	0.00822 (5)	0.00154 (6)	0.00017 (3)	−0.00158 (5)
Cl1	0.0265 (3)	0.0165 (2)	0.0140 (2)	−0.0048 (2)	0.0032 (2)	−0.0015 (2)
N1	0.0139 (9)	0.0141 (8)	0.0096 (8)	0.0001 (8)	0.0003 (7)	−0.0017 (7)
C1	0.0145 (10)	0.0156 (11)	0.0126 (9)	−0.0004 (9)	0.0014 (8)	0.0006 (8)
C2	0.0168 (11)	0.0133 (11)	0.0132 (10)	−0.0030 (9)	0.0050 (8)	−0.0033 (8)
C3	0.0370 (13)	0.0158 (10)	0.0165 (10)	0.0026 (13)	0.0077 (9)	−0.0002 (11)
C4	0.0122 (10)	0.0181 (11)	0.0111 (10)	−0.0041 (9)	0.0019 (8)	−0.0013 (8)
C5	0.0222 (12)	0.0232 (12)	0.0109 (10)	−0.0042 (10)	0.0018 (9)	−0.0026 (9)
C6	0.0168 (9)	0.0174 (10)	0.0131 (9)	0.0019 (11)	−0.0013 (7)	0.0011 (11)
C7	0.0166 (11)	0.0173 (12)	0.0147 (10)	0.0027 (8)	0.0008 (8)	−0.0010 (8)

Geometric parameters (Å, °)

Pt1—N1i	2.0148 (18)	C3—H3B	0.9800
Pt1—N1	2.0148 (18)	C3—H3C	0.9800
Pt1—Cl1i	2.2901 (6)	C4—C6	1.382 (3)
Pt1—Cl1	2.2901 (6)	C4—C5	1.495 (3)
N1—C7	1.343 (3)	C5—H5A	0.9800
N1—C1	1.347 (3)	C5—H5B	0.9800
C1—C2	1.384 (3)	C5—H5C	0.9800
C1—H1	0.9500	C6—C7	1.380 (3)
C2—C4	1.398 (3)	C6—H6	0.9500
C2—C3	1.495 (3)	C7—H7	0.9500
C3—H3A	0.9800
N1i—Pt1—N1	180.0	C2—C3—H3C	109.5
N1i—Pt1—Cl1i	89.85 (6)	H3A—C3—H3C	109.5
N1—Pt1—Cl1i	90.15 (6)	H3B—C3—H3C	109.5
N1i—Pt1—Cl1	90.15 (6)	C6—C4—C2	117.88 (19)
N1—Pt1—Cl1	89.85 (6)	C6—C4—C5	121.0 (2)
Cl1i—Pt1—Cl1	180.0	C2—C4—C5	121.1 (2)
C7—N1—C1	118.30 (19)	C4—C5—H5A	109.5
C7—N1—Pt1	119.91 (15)	C4—C5—H5B	109.5
C1—N1—Pt1	121.79 (15)	H5A—C5—H5B	109.5
N1—C1—C2	123.1 (2)	C4—C5—H5C	109.5
N1—C1—H1	118.5	H5A—C5—H5C	109.5
C2—C1—H1	118.5	H5B—C5—H5C	109.5
C1—C2—C4	118.5 (2)	C7—C6—C4	120.6 (2)
C1—C2—C3	119.8 (2)	C7—C6—H6	119.7
C4—C2—C3	121.78 (19)	C4—C6—H6	119.7
C2—C3—H3A	109.5	N1—C7—C6	121.6 (2)
C2—C3—H3B	109.5	N1—C7—H7	119.2
H3A—C3—H3B	109.5	C6—C7—H7	119.2

Symmetry codes: (i) −x, −y, −z.

Table 2 Geometrical parameters (Å) for the trans-[PtCl₂L₂] (L = pyridine-type ligand) complexes.

L	Pt—N	Pt—Cl	N—Pt—Cl
4-picoline [1]	2.024 (5)	2.3046 (18)	90.16 (12)
N-nitroxyethylnicotinamide [2]	2.019 (8)	2.311 (3)	90.8 (2)
4-vinylpyridine [3]	2.021 (3)	2.3000 (9)	89.9 (8)
3-fluoropyridine [4]	2.0177 (20)	2.3013 (12)	89.86 (9)
3-chloropyridine [4]	2.015 (3)	2.3001 (8)	90.55 (8)
3-bromopyridine [4]	1.992 (6)	2.3106 (16)	90.40 (19)
3-iodopyridine [4]	2.019 (5)	2.303 (3)	89.7 (2)
2,6-bis(hydroxymethyl)pyridine [5]	2.040 (7)	2.306 (3)	90m
pyridine [6]	1.977 (2)	2.308 (3)	88.01 (6)

In all structures Pt atom is located on an inversion centre. ^m = Pt is on a mirror plane. [1] Tessier & Rochon (1999); [2] Eremenko et al. (1997); [3] Shaver et al. (2000); [4] Zordan et al. (2005); [5] Rochon et al. (1996); [6] Colamarino & Orioli (1975).