Chlorido[1,1′-(5-methyl-1,3-phenyl­ene)bis­(3,5-dimethyl-1H-imidazol-2-yl­idene)]platinum(II)

Peng, K.-J.; Wang, Z.-X.; Wan, W.

doi:10.1107/S1600536813006545

metal-organic compounds

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ISSN: 2056-9890

Volume 69| Part 4| April 2013| Page m218

doi:10.1107/S1600536813006545

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Chlorido[1,1′-(5-methyl-1,3-phenylene)bis(3,5-dimethyl-1H-imidazol-2-ylidene)]platinum(II)

Kui-Juan Peng,^a Zi-Xing Wang ^b ^* and Wen Wan ^a

^aDepartment of Chemistry, Shanghai University, Shanghai 200444, People's Republic of China, and ^bKey Laboratory of Advanced Display and System Applications, Ministry of Education, Shanghai University, Shanghai 200072, People's Republic of China
^*Correspondence e-mail: zxwang78@shu.edu.cn

(Received 23 February 2013; accepted 7 March 2013; online 16 March 2013)

In the title compound, [Pt(C₁₇H₁₉N₄)Cl], the Pt^II cation is C,C′,C′′-chelated by the 1,1′-(5-methyl-1,3-phenylene)bis(3,5-dimethyl-1H-imidazolylidene) anion and coordinated by a Cl⁻ anion in a distorted square-planar coordination geometry. π–π stacking is observed between nearly parallel imidazole and benzene rings of adjacent molecules, the centroid–centroid distance being 3.802 (4) Å.

Related literature

For the application of Pt^II complexes in organic light-emitting diodes, see: Yang et al. (2008 ); Bakken et al. (2012 ); Fleetham et al. (2012 ). For a related compound, see: Wang et al. (2010 ).

Experimental

Crystal data

[Pt(C₁₇H₁₉N₄)Cl]
M_r = 509.90
Monoclinic, P 2₁ /n
a = 11.042 (5) Å
b = 14.552 (6) Å
c = 11.524 (5) Å
β = 116.049 (4)°
V = 1663.6 (12) Å³
Z = 4
Mo Kα radiation
μ = 8.60 mm⁻¹
T = 296 K
0.16 × 0.13 × 0.07 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ) T_min = 0.340, T_max = 0.584
8411 measured reflections
2958 independent reflections
2579 reflections with I > 2σ(I)
R_int = 0.026

Refinement

R[F² > 2σ(F²)] = 0.029
wR(F²) = 0.080
S = 1.07
2958 reflections
189 parameters
H-atom parameters constrained
Δρ_max = 1.78 e Å⁻³
Δρ_min = −2.04 e Å⁻³

Table 1
Selected bond lengths (Å)

Pt1—C1	1.909 (6)
Pt1—C9	2.045 (6)
Pt1—C10	2.040 (6)
Pt1—Cl1	2.4295 (19)

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536813006545/xu5680sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813006545/xu5680Isup2.hkl

checkCIF report

Comment top

Square planar Pt(II) complexes have attracted much attention due to their potential application in organic light-emitting diodes (Yang et al., 2008). Pt(N—C—N)X (where N—C—N,di(2-pyridinyl)benzene-based tridentate ligands, X=monoanionic ligands), are reported to have much higher quantum yield than Pt(C—N)(LX) (where C—N,2-pyridylphenylbased bidentate ligands, LX, monoanionic ancillary ligands) with similar structures (Wang et al., 2010), so designing and studying tridentate Pt complexes for application in blue and white phosphorescent OLEDs is a worthwhile undertaking (Fleetham et al., 2012). Replacing pyridinyl group with methyl-imidazolyl group could potentially weaken the intermolecular interaction, resultingin a blue-shifted excimer emission (Bakken et al.,2012). Here we report a new Pt(C—C—C)X type of Pt complex using methyl-imidazolyl as ligands, structure shown in Figure 1.

In the title molecule the Pt(1)-C(1)-C(9) plane is almost coplanar with the benzene ring and with the plane of C(9)-N(1)-N(2) ring, the dihedral angles being 1.57° and 2.00°, respectively. The other Pt1 ring (Pt(1)-C(1)-C(10)) is, however, is slightly different, makes dihedral angles of 1.28° and 2.00° with the benzene ring and the plane of C(10)-N(3)-N(4), respectively. The Pt(II) centre forms a distorted square planar and makes an angle of 1.95° between the Pt(1)-C(1)-C(10) ring and Pt(1)-C(1)-C(9) ring; the bond lengths of Pt(1)—C(9) and Pt(1)—C(10) are almost the same, being 2.040 (4) and 2.045 (4), respectively. The angles of C(1)-Pt(1)-C(9) and C(1)-Pt(1)-C(10) being 79.38 (19)° and 79.62 (19)°, are also very near.

Related literature top

For the application of Pt^II complexes in organic light-emitting diodes, see: Yang et al. (2008); Bakken et al. (2012); Fleetham et al. (2012). For a related compound, see: Wang et al. (2010).

Experimental top

A mixture of 1,1'-[5-methyl-1,3-phenylene]bis[3,5-dimethyl-1H-imidazolium] diiodide (1 mmol) and 0.5 mmol silver oxide was stirred in a solution of 100 mL acetonitrile for 5 h at room temperature before 1equiv. Platinum chloride and 1eq. potassium carbonate were added. The reaction mixture was heated to reflux for an additional 24 h. Then the mixture was cooled to room temperature before 100 mL water was added. The resulting yellow precipitate was filtered off and washed with excessive methanol, water, and ether and dried under vacuum. The light yellowish product (in 20% yield) was obtained after thermal evaporation under high vacuum.¹H NMR (500 MHz, δ in p.p.m., DMSO): 6.84 (s, 2H), 6.02 (s, 2H), 2.77 (s, 6H), 2.71(s, 6H), 2.35 (s, 3H).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids (arbitrary spheres for H atoms)

Chlorido[1,1'-(5-methyl-1,3-phenylene)bis(3,5-dimethyl-1H-imidazol-2-ylidene)]platinum(II) top

Crystal data top

[Pt(C₁₇H₁₉N₄)Cl]	F(000) = 976
M_r = 509.90	D_x = 2.036 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 4377 reflections
a = 11.042 (5) Å	θ = 2.4–27.5°
b = 14.552 (6) Å	µ = 8.60 mm⁻¹
c = 11.524 (5) Å	T = 296 K
β = 116.049 (4)°	Block, colorless
V = 1663.6 (12) Å³	0.16 × 0.13 × 0.07 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	2958 independent reflections
Radiation source: fine-focus sealed tube	2579 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.026
Detector resolution: 10 pixels mm^-1	θ_max = 25.0°, θ_min = 2.1°
ϕ and ω scans	h = −12→13
Absorption correction: multi-scan (SADABS; Bruker, 2001)	k = −16→17
T_min = 0.340, T_max = 0.584	l = −12→13
8411 measured reflections

Refinement top

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)] = 0.029	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.080	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0412P)² + 5.3708P] where P = (F_o² + 2F_c²)/3
2958 reflections	(Δ/σ)_max = 0.001
189 parameters	Δρ_max = 1.78 e Å⁻³
0 restraints	Δρ_min = −2.04 e Å⁻³

Crystal data top

[Pt(C₁₇H₁₉N₄)Cl]	V = 1663.6 (12) Å³
M_r = 509.90	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 11.042 (5) Å	µ = 8.60 mm⁻¹
b = 14.552 (6) Å	T = 296 K
c = 11.524 (5) Å	0.16 × 0.13 × 0.07 mm
β = 116.049 (4)°

Data collection top

Bruker APEXII CCD diffractometer	2958 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2001)	2579 reflections with I > 2σ(I)
T_min = 0.340, T_max = 0.584	R_int = 0.026
8411 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.029	0 restraints
wR(F²) = 0.080	H-atom parameters constrained
S = 1.07	Δρ_max = 1.78 e Å⁻³
2958 reflections	Δρ_min = −2.04 e Å⁻³
189 parameters

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

	x	y	z	U_iso*/U_eq
Pt1	0.48107 (2)	0.137708 (16)	0.63220 (2)	0.02999 (11)
C1	0.6140 (6)	0.1354 (4)	0.5684 (6)	0.0310 (14)
C2	0.6974 (6)	0.0590 (4)	0.5917 (6)	0.0296 (13)
C3	0.7964 (6)	0.0559 (4)	0.5471 (6)	0.0345 (14)
H3	0.8522	0.0049	0.5631	0.041*
C4	0.8098 (7)	0.1319 (4)	0.4772 (7)	0.0390 (16)
C5	0.7255 (6)	0.2074 (4)	0.4513 (6)	0.0335 (14)
H5	0.7340	0.2566	0.4039	0.040*
C6	0.6260 (6)	0.2085 (4)	0.4978 (6)	0.0287 (13)
C7	0.5042 (7)	0.3599 (4)	0.4217 (7)	0.0387 (16)
C8	0.3955 (7)	0.3958 (5)	0.4341 (7)	0.0450 (17)
H8	0.3540	0.4519	0.4023	0.054*
C9	0.4420 (6)	0.2595 (4)	0.5339 (6)	0.0340 (7)
C10	0.5694 (6)	0.0138 (4)	0.7018 (6)	0.0362 (7)
C11	0.6528 (8)	−0.1257 (5)	0.7757 (7)	0.0462 (18)
H11	0.6655	−0.1825	0.8164	0.055*
C12	0.7198 (7)	−0.0930 (4)	0.7090 (6)	0.0362 (14)
C13	0.9173 (9)	0.1298 (6)	0.4307 (10)	0.060 (2)
H13A	0.9079	0.1825	0.3773	0.091*
H13B	0.9082	0.0749	0.3815	0.091*
H13C	1.0045	0.1308	0.5035	0.091*
C14	0.2445 (8)	0.3377 (6)	0.5408 (9)	0.056 (2)
H14A	0.1713	0.2998	0.4838	0.084*
H14B	0.2146	0.4003	0.5341	0.084*
H14C	0.2744	0.3167	0.6281	0.084*
C15	0.5829 (8)	0.4025 (5)	0.3576 (8)	0.053 (2)
H15A	0.6767	0.4044	0.4175	0.080*
H15B	0.5510	0.4639	0.3308	0.080*
H15C	0.5714	0.3667	0.2836	0.080*
C16	0.4651 (9)	−0.0611 (6)	0.8318 (8)	0.057 (2)
H16A	0.4607	−0.0018	0.8661	0.085*
H16B	0.4962	−0.1056	0.9003	0.085*
H16C	0.3771	−0.0783	0.7677	0.085*
C17	0.8297 (8)	−0.1388 (4)	0.6863 (8)	0.0439 (17)
H17A	0.8081	−0.1359	0.5961	0.066*
H17B	0.8375	−0.2019	0.7130	0.066*
H17C	0.9136	−0.1078	0.7353	0.066*
Cl1	0.3130 (2)	0.14031 (13)	0.7148 (2)	0.0560 (5)
N1	0.5316 (5)	0.2784 (4)	0.4818 (5)	0.0340 (7)
N2	0.3591 (5)	0.3319 (4)	0.5039 (5)	0.0340 (7)
N3	0.6696 (5)	−0.0091 (4)	0.6648 (5)	0.0362 (7)
N4	0.5613 (5)	−0.0576 (4)	0.7712 (5)	0.0362 (7)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Pt1	0.02833 (16)	0.03514 (16)	0.03016 (16)	−0.00059 (10)	0.01622 (11)	−0.00590 (10)
C1	0.025 (3)	0.035 (3)	0.033 (3)	0.000 (3)	0.013 (3)	−0.007 (3)
C2	0.032 (3)	0.027 (3)	0.029 (3)	0.003 (3)	0.013 (3)	0.000 (2)
C3	0.032 (3)	0.036 (3)	0.037 (4)	0.008 (3)	0.017 (3)	0.003 (3)
C4	0.034 (4)	0.048 (4)	0.041 (4)	0.007 (3)	0.021 (3)	0.002 (3)
C5	0.035 (3)	0.033 (3)	0.035 (3)	0.002 (3)	0.018 (3)	0.004 (3)
C6	0.031 (3)	0.026 (3)	0.027 (3)	0.005 (2)	0.012 (3)	−0.001 (2)
C7	0.041 (4)	0.039 (4)	0.035 (4)	0.004 (3)	0.016 (3)	0.002 (3)
C8	0.048 (4)	0.038 (4)	0.049 (4)	0.014 (3)	0.022 (4)	0.004 (3)
C9	0.0303 (17)	0.0384 (17)	0.0344 (18)	0.0063 (14)	0.0151 (14)	−0.0035 (14)
C10	0.0376 (18)	0.0386 (18)	0.0329 (18)	−0.0016 (15)	0.0159 (15)	−0.0006 (14)
C11	0.051 (4)	0.041 (4)	0.039 (4)	0.000 (3)	0.012 (4)	0.008 (3)
C12	0.040 (4)	0.032 (3)	0.030 (3)	0.002 (3)	0.009 (3)	0.001 (3)
C13	0.053 (5)	0.069 (6)	0.081 (6)	0.021 (4)	0.050 (5)	0.019 (4)
C14	0.052 (5)	0.061 (5)	0.064 (5)	0.024 (4)	0.033 (4)	0.002 (4)
C15	0.067 (5)	0.046 (4)	0.062 (5)	0.017 (4)	0.042 (4)	0.024 (4)
C16	0.071 (5)	0.067 (5)	0.044 (4)	−0.012 (4)	0.036 (4)	0.001 (4)
C17	0.045 (4)	0.038 (4)	0.048 (4)	0.003 (3)	0.019 (4)	0.003 (3)
Cl1	0.0584 (12)	0.0608 (12)	0.0749 (14)	0.0069 (9)	0.0531 (12)	−0.0027 (9)
N1	0.0303 (17)	0.0384 (17)	0.0344 (18)	0.0063 (14)	0.0151 (14)	−0.0035 (14)
N2	0.0303 (17)	0.0384 (17)	0.0344 (18)	0.0063 (14)	0.0151 (14)	−0.0035 (14)
N3	0.0376 (18)	0.0386 (18)	0.0329 (18)	−0.0016 (15)	0.0159 (15)	−0.0006 (14)
N4	0.0376 (18)	0.0386 (18)	0.0329 (18)	−0.0016 (15)	0.0159 (15)	−0.0006 (14)

Geometric parameters (Å, º) top

Pt1—C1	1.909 (6)	C10—N3	1.389 (8)
Pt1—C9	2.045 (6)	C11—C12	1.366 (10)
Pt1—C10	2.040 (6)	C11—N4	1.400 (9)
Pt1—Cl1	2.4295 (19)	C11—H11	0.9300
C1—C6	1.380 (8)	C12—N3	1.345 (8)
C1—C2	1.392 (8)	C12—C17	1.504 (10)
C2—C3	1.398 (8)	C13—H13A	0.9600
C2—N3	1.419 (8)	C13—H13B	0.9600
C3—C4	1.414 (9)	C13—H13C	0.9600
C3—H3	0.9300	C14—N2	1.504 (9)
C4—C5	1.385 (9)	C14—H14A	0.9600
C4—C13	1.502 (10)	C14—H14B	0.9600
C5—C6	1.419 (8)	C14—H14C	0.9600
C5—H5	0.9300	C15—H15A	0.9600
C6—N1	1.409 (7)	C15—H15B	0.9600
C7—N1	1.339 (8)	C15—H15C	0.9600
C7—C8	1.372 (10)	C16—N4	1.507 (9)
C7—C15	1.499 (10)	C16—H16A	0.9600
C8—N2	1.399 (9)	C16—H16B	0.9600
C8—H8	0.9300	C16—H16C	0.9600
C9—N2	1.337 (8)	C17—H17A	0.9600
C9—N1	1.393 (8)	C17—H17B	0.9600
C10—N4	1.338 (8)	C17—H17C	0.9600

C1—Pt1—C10	79.6 (3)	C4—C13—H13A	109.5
C1—Pt1—C9	79.2 (2)	C4—C13—H13B	109.5
C10—Pt1—C9	158.8 (2)	H13A—C13—H13B	109.5
C1—Pt1—Cl1	179.6 (2)	C4—C13—H13C	109.5
C10—Pt1—Cl1	100.12 (18)	H13A—C13—H13C	109.5
C9—Pt1—Cl1	101.06 (17)	H13B—C13—H13C	109.5
C6—C1—C2	120.2 (6)	N2—C14—H14A	109.5
C6—C1—Pt1	120.1 (4)	N2—C14—H14B	109.5
C2—C1—Pt1	119.6 (5)	H14A—C14—H14B	109.5
C1—C2—C3	120.9 (6)	N2—C14—H14C	109.5
C1—C2—N3	112.1 (5)	H14A—C14—H14C	109.5
C3—C2—N3	127.1 (5)	H14B—C14—H14C	109.5
C2—C3—C4	118.5 (6)	C7—C15—H15A	109.5
C2—C3—H3	120.7	C7—C15—H15B	109.5
C4—C3—H3	120.7	H15A—C15—H15B	109.5
C5—C4—C3	121.0 (6)	C7—C15—H15C	109.5
C5—C4—C13	120.0 (6)	H15A—C15—H15C	109.5
C3—C4—C13	119.0 (6)	H15B—C15—H15C	109.5
C4—C5—C6	119.1 (6)	N4—C16—H16A	109.5
C4—C5—H5	120.4	N4—C16—H16B	109.5
C6—C5—H5	120.4	H16A—C16—H16B	109.5
C1—C6—N1	112.2 (5)	N4—C16—H16C	109.5
C1—C6—C5	120.2 (5)	H16A—C16—H16C	109.5
N1—C6—C5	127.6 (5)	H16B—C16—H16C	109.5
N1—C7—C8	107.0 (6)	C12—C17—H17A	109.5
N1—C7—C15	124.9 (6)	C12—C17—H17B	109.5
C8—C7—C15	128.1 (6)	H17A—C17—H17B	109.5
C7—C8—N2	107.0 (6)	C12—C17—H17C	109.5
C7—C8—H8	126.5	H17A—C17—H17C	109.5
N2—C8—H8	126.5	H17B—C17—H17C	109.5
N2—C9—N1	105.5 (5)	C7—N1—C9	110.9 (5)
N2—C9—Pt1	141.3 (5)	C7—N1—C6	133.9 (6)
N1—C9—Pt1	113.2 (4)	C9—N1—C6	115.1 (5)
N4—C10—N3	105.6 (5)	C9—N2—C8	109.6 (5)
N4—C10—Pt1	140.8 (5)	C9—N2—C14	122.4 (6)
N3—C10—Pt1	113.5 (4)	C8—N2—C14	128.0 (6)
C12—C11—N4	107.0 (6)	C12—N3—C10	110.7 (5)
C12—C11—H11	126.5	C12—N3—C2	134.3 (5)
N4—C11—H11	126.5	C10—N3—C2	115.1 (5)
N3—C12—C11	107.1 (6)	C10—N4—C11	109.6 (6)
N3—C12—C17	124.5 (6)	C10—N4—C16	123.4 (6)
C11—C12—C17	128.4 (6)	C11—N4—C16	127.0 (6)

Experimental details

Crystal data
Chemical formula	[Pt(C₁₇H₁₉N₄)Cl]
M_r	509.90
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	296
a, b, c (Å)	11.042 (5), 14.552 (6), 11.524 (5)
β (°)	116.049 (4)
V (Å³)	1663.6 (12)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	8.60
Crystal size (mm)	0.16 × 0.13 × 0.07

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2001)
T_min, T_max	0.340, 0.584
No. of measured, independent and observed [I > 2σ(I)] reflections	8411, 2958, 2579
R_int	0.026
(sin θ/λ)_max (Å⁻¹)	0.596

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.029, 0.080, 1.07
No. of reflections	2958
No. of parameters	189
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.78, −2.04

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top

Pt1—C1	1.909 (6)	Pt1—C10	2.040 (6)
Pt1—C9	2.045 (6)	Pt1—Cl1	2.4295 (19)

Acknowledgements

Z-XW thanks the Foundation for SRF for ROCS, SEM, Innovative Foundation of Shanghai University, and Shanghai Municipal Education Commission Special Research Fund for Excellent Young College and University Teachers.

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