A luminescent bis­(pyrid­yl)-substituted benz­imidazole platinum(II) complex exhibiting an inter­molecular anagostic inter­action

The photophysical properties of transition metal complexes of the 5,6-dimethyl-2-(pyridin-2-yl)-1-(pyridin-2-ylmeth­yl)-1H-benzimidazole ligand are of inter­est. Di­chlorido­[5,6-dimethyl-2-(pyridin-2-yl)-1-(pyridin-2-ylmeth­yl)-1H-benzimidazole-κ²N²,N³]platinum(II), [PtCl₂(C₂₀H₁₈N₄)], is luminescent in the solid state at room temperature. The compound displays a distorted square-planar coordination geometry. The Pt—N(imidazole) bond length is shorter than the Pt—N(pyridine) bond length. The extended structure reveals that symmetry-related mol­ecules display weak C—H...N, C—H...Cl, and C—H...Pt hydrogen-bonding inter­actions that are clearly discernable in the Hirshfeld surface and fingerprint plots. The inter­molecular C—H...Pt and C—H...N inter­actions have been explored using density functional theory. The result of an analysis of the distance dependence of C—H...Pt yields a value consistent with that observed in the solid-state structure. The energy of inter­action for the C—H...Pt inter­action is found to be about −11 kJ mol⁻¹.

Computing details

Data collection: APEX2 (Bruker, 2013); cell refinement: SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: PLATON (Spek, 2009) and Mercury (Macrae et al., 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Dichlorido{5,6-dimethyl-2-(pyridin-2-yl)-1-(pyridin-2-ylmethyl)-1H-benzimidazole-κ²N²,N³}platinum(II)

Crystal data

[PtCl2(C20H18N4)]	F(000) = 1112
Mr = 580.37	Dx = 1.978 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 10.6134 (14) Å	Cell parameters from 4378 reflections
b = 15.7166 (16) Å	θ = 2.3–25.7°
c = 11.8754 (17) Å	µ = 7.49 mm^−1
β = 100.376 (5)°	T = 200 K
V = 1948.5 (4) Å^3	Parallelepiped, clear orange
Z = 4	0.30 × 0.30 × 0.10 mm

Data collection

Bruker SMART X2S benchtop diffractometer	4257 independent reflections
Radiation source: sealed microfocus tube	3302 reflections with I > 2σ(I)
Doubly curved silicon crystal monochromator	Rint = 0.059
Detector resolution: 8.3330 pixels mm^-1	θmax = 27.1°, θmin = 2.3°
ω scans	h = −13→7
Absorption correction: multi-scan (SADABS; Bruker, 2013)	k = −18→19
Tmin = 0.38, Tmax = 0.52	l = −15→15
17697 measured reflections

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)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.069	H-atom parameters constrained
S = 1.05	w = 1/[σ^2(Fo^2) + (0.0239P)^2] where P = (Fo^2 + 2Fc^2)/3
4257 reflections	(Δ/σ)max = 0.001
246 parameters	Δρmax = 2.30 e Å^−3
0 restraints	Δρmin = −0.89 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Pt1	0.68067 (2)	0.59249 (2)	0.61444 (2)	0.02459 (8)
Cl1	0.77201 (12)	0.52216 (9)	0.77871 (13)	0.0402 (4)
Cl2	0.88400 (13)	0.62712 (11)	0.58952 (15)	0.0500 (4)
N1	0.4961 (4)	0.5684 (2)	0.6216 (4)	0.0246 (10)
N2	0.2894 (4)	0.5832 (2)	0.5472 (4)	0.0258 (10)
N3	0.5929 (4)	0.6543 (2)	0.4708 (4)	0.0262 (10)
N4	0.2100 (5)	0.7468 (3)	0.5602 (4)	0.0424 (13)
C1	0.4263 (4)	0.5256 (3)	0.6944 (5)	0.0243 (11)
C2	0.2964 (5)	0.5357 (3)	0.6464 (5)	0.0273 (12)
C3	0.2013 (5)	0.5002 (3)	0.6993 (5)	0.0326 (13)
H3	0.1133	0.5088	0.6684	0.039*
C4	0.2376 (6)	0.4525 (3)	0.7971 (5)	0.0373 (14)
C5	0.3714 (5)	0.4417 (3)	0.8451 (5)	0.0341 (13)
C6	0.4666 (5)	0.4793 (3)	0.7922 (5)	0.0323 (13)
H6	0.555	0.4728	0.8231	0.039*
C7	0.4107 (4)	0.6021 (3)	0.5360 (4)	0.0226 (11)
C8	0.4618 (5)	0.6507 (3)	0.4494 (5)	0.0259 (12)
C9	0.3925 (5)	0.6914 (3)	0.3537 (5)	0.0344 (14)
H9	0.3017	0.6871	0.3369	0.041*
C10	0.4565 (6)	0.7375 (3)	0.2843 (5)	0.0411 (15)
H10	0.4101	0.7671	0.2201	0.049*
C11	0.5889 (6)	0.7412 (3)	0.3076 (5)	0.0400 (15)
H11	0.6342	0.7731	0.26	0.048*
C12	0.6536 (5)	0.6980 (3)	0.4007 (5)	0.0330 (13)
H12	0.7446	0.6992	0.4155	0.04*
C13	0.1693 (5)	0.6084 (3)	0.4725 (5)	0.0316 (13)
H13A	0.0972	0.5778	0.4967	0.038*
H13B	0.1727	0.591	0.393	0.038*
C14	0.1443 (5)	0.7031 (3)	0.4747 (5)	0.0294 (13)
C15	0.0569 (6)	0.7390 (4)	0.3881 (6)	0.0488 (17)
H15	0.0117	0.7052	0.3278	0.059*
C16	0.0367 (7)	0.8262 (4)	0.3915 (7)	0.065 (2)
H16	−0.0214	0.8536	0.3324	0.078*
C17	0.1012 (7)	0.8714 (4)	0.4803 (7)	0.060 (2)
H17	0.0873	0.9309	0.4858	0.072*
C18	0.1865 (7)	0.8303 (4)	0.5617 (6)	0.059 (2)
H18	0.232	0.863	0.6232	0.071*
C41	0.1378 (6)	0.4107 (4)	0.8548 (6)	0.0523 (18)
H41A	0.0524	0.4298	0.8181	0.078*
H41B	0.1528	0.4265	0.936	0.078*
H41C	0.1436	0.3488	0.8478	0.078*
C51	0.4093 (7)	0.3882 (4)	0.9496 (6)	0.0550 (19)
H51A	0.5027	0.3896	0.9732	0.083*
H51B	0.3813	0.3295	0.9326	0.083*
H51C	0.369	0.4105	1.0115	0.083*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Pt1	0.02383 (11)	0.02320 (13)	0.02634 (13)	0.00094 (8)	0.00340 (8)	−0.00134 (10)
Cl1	0.0326 (7)	0.0456 (9)	0.0396 (9)	−0.0005 (6)	−0.0012 (6)	0.0088 (7)
Cl2	0.0287 (7)	0.0699 (11)	0.0518 (11)	−0.0063 (7)	0.0082 (7)	0.0102 (9)
N1	0.024 (2)	0.021 (2)	0.026 (3)	0.0047 (17)	−0.0011 (18)	−0.0039 (19)
N2	0.024 (2)	0.021 (2)	0.032 (3)	0.0038 (17)	0.0053 (18)	−0.002 (2)
N3	0.033 (2)	0.019 (2)	0.026 (3)	0.0031 (18)	0.0048 (19)	−0.001 (2)
N4	0.053 (3)	0.025 (3)	0.045 (4)	0.007 (2)	−0.005 (3)	−0.008 (2)
C1	0.028 (3)	0.018 (3)	0.029 (3)	0.001 (2)	0.009 (2)	−0.003 (2)
C2	0.029 (3)	0.022 (3)	0.031 (3)	−0.001 (2)	0.006 (2)	−0.006 (2)
C3	0.033 (3)	0.028 (3)	0.036 (4)	−0.002 (2)	0.006 (2)	−0.006 (3)
C4	0.051 (4)	0.026 (3)	0.039 (4)	−0.010 (3)	0.021 (3)	−0.007 (3)
C5	0.047 (4)	0.026 (3)	0.032 (4)	−0.002 (3)	0.014 (3)	−0.004 (3)
C6	0.054 (4)	0.020 (3)	0.022 (3)	0.000 (2)	0.004 (3)	0.002 (2)
C7	0.026 (3)	0.020 (3)	0.022 (3)	0.002 (2)	0.005 (2)	−0.006 (2)
C8	0.031 (3)	0.023 (3)	0.024 (3)	0.006 (2)	0.005 (2)	−0.003 (2)
C9	0.032 (3)	0.037 (3)	0.032 (4)	0.003 (2)	0.001 (2)	0.005 (3)
C10	0.052 (4)	0.038 (3)	0.032 (4)	0.008 (3)	0.002 (3)	0.009 (3)
C11	0.068 (4)	0.026 (3)	0.030 (4)	−0.004 (3)	0.017 (3)	0.008 (3)
C12	0.042 (3)	0.029 (3)	0.029 (3)	−0.005 (2)	0.009 (3)	−0.001 (3)
C13	0.020 (3)	0.031 (3)	0.040 (4)	0.005 (2)	−0.004 (2)	−0.002 (3)
C14	0.026 (3)	0.032 (3)	0.030 (3)	0.006 (2)	0.005 (2)	−0.001 (3)
C15	0.051 (4)	0.050 (4)	0.040 (4)	0.013 (3)	−0.006 (3)	−0.002 (3)
C16	0.083 (5)	0.058 (5)	0.051 (5)	0.039 (4)	0.005 (4)	0.026 (4)
C17	0.080 (5)	0.042 (4)	0.063 (6)	0.023 (4)	0.029 (4)	0.005 (4)
C18	0.077 (5)	0.037 (4)	0.058 (5)	0.011 (3)	−0.003 (4)	−0.014 (4)
C41	0.056 (4)	0.051 (4)	0.056 (5)	−0.013 (3)	0.026 (4)	0.001 (4)
C51	0.072 (5)	0.052 (4)	0.043 (5)	−0.014 (3)	0.017 (4)	0.011 (3)

Geometric parameters (Å, º)

Pt1—N1	2.012 (4)	C9—C10	1.368 (8)
Pt1—N3	2.037 (4)	C9—H9	0.95
Pt1—Cl2	2.2959 (14)	C10—C11	1.384 (8)
Pt1—Cl1	2.2992 (14)	C10—H10	0.95
N1—C7	1.343 (6)	C11—C12	1.372 (7)
N1—C1	1.406 (6)	C11—H11	0.95
N2—C7	1.352 (6)	C12—H12	0.95
N2—C2	1.385 (7)	C13—C14	1.513 (6)
N2—C13	1.470 (6)	C13—H13A	0.99
N3—C12	1.332 (7)	C13—H13B	0.99
N3—C8	1.370 (6)	C14—C15	1.375 (7)
N4—C14	1.317 (7)	C15—C16	1.389 (8)
N4—C18	1.337 (7)	C15—H15	0.95
C1—C6	1.372 (7)	C16—C17	1.351 (9)
C1—C2	1.403 (6)	C16—H16	0.95
C2—C3	1.398 (7)	C17—C18	1.363 (9)
C3—C4	1.378 (8)	C17—H17	0.95
C3—H3	0.95	C18—H18	0.95
C4—C5	1.441 (8)	C41—H41A	0.98
C4—C41	1.512 (8)	C41—H41B	0.98
C5—C6	1.412 (7)	C41—H41C	0.98
C5—C51	1.493 (8)	C51—H51A	0.98
C6—H6	0.95	C51—H51B	0.98
C7—C8	1.461 (7)	C51—H51C	0.98
C8—C9	1.393 (7)
N1—Pt1—N3	79.81 (17)	C9—C10—C11	119.9 (5)
N1—Pt1—Cl2	174.27 (13)	C9—C10—H10	120.1
N3—Pt1—Cl2	94.46 (12)	C11—C10—H10	120.1
N1—Pt1—Cl1	97.97 (13)	C12—C11—C10	119.0 (5)
N3—Pt1—Cl1	177.73 (12)	C12—C11—H11	120.5
Cl2—Pt1—Cl1	87.76 (5)	C10—C11—H11	120.5
C7—N1—C1	107.2 (4)	N3—C12—C11	122.0 (5)
C7—N1—Pt1	115.0 (3)	N3—C12—H12	119.0
C1—N1—Pt1	137.7 (3)	C11—C12—H12	119.0
C7—N2—C2	107.2 (4)	N2—C13—C14	113.0 (4)
C7—N2—C13	128.2 (5)	N2—C13—H13A	109.0
C2—N2—C13	124.6 (4)	C14—C13—H13A	109.0
C12—N3—C8	119.7 (5)	N2—C13—H13B	109.0
C12—N3—Pt1	124.7 (4)	C14—C13—H13B	109.0
C8—N3—Pt1	115.6 (3)	H13A—C13—H13B	107.8
C14—N4—C18	116.6 (5)	N4—C14—C15	123.7 (5)
C6—C1—C2	122.5 (5)	N4—C14—C13	117.1 (5)
C6—C1—N1	131.0 (5)	C15—C14—C13	119.2 (5)
C2—C1—N1	106.5 (4)	C14—C15—C16	118.0 (6)
N2—C2—C3	131.6 (5)	C14—C15—H15	121.0
N2—C2—C1	107.8 (4)	C16—C15—H15	121.0
C3—C2—C1	120.6 (5)	C17—C16—C15	118.9 (6)
C4—C3—C2	118.8 (5)	C17—C16—H16	120.6
C4—C3—H3	120.6	C15—C16—H16	120.6
C2—C3—H3	120.6	C16—C17—C18	118.9 (6)
C3—C4—C5	120.2 (5)	C16—C17—H17	120.6
C3—C4—C41	120.4 (6)	C18—C17—H17	120.6
C5—C4—C41	119.4 (6)	N4—C18—C17	123.9 (6)
C6—C5—C4	120.5 (5)	N4—C18—H18	118.1
C6—C5—C51	119.9 (5)	C17—C18—H18	118.1
C4—C5—C51	119.6 (5)	C4—C41—H41A	109.5
C1—C6—C5	117.4 (5)	C4—C41—H41B	109.5
C1—C6—H6	121.3	H41A—C41—H41B	109.5
C5—C6—H6	121.3	C4—C41—H41C	109.5
N1—C7—N2	111.3 (4)	H41A—C41—H41C	109.5
N1—C7—C8	117.0 (4)	H41B—C41—H41C	109.5
N2—C7—C8	131.7 (5)	C5—C51—H51A	109.5
N3—C8—C9	120.1 (5)	C5—C51—H51B	109.5
N3—C8—C7	112.6 (4)	H51A—C51—H51B	109.5
C9—C8—C7	127.3 (5)	C5—C51—H51C	109.5
C10—C9—C8	119.3 (5)	H51A—C51—H51C	109.5
C10—C9—H9	120.4	H51B—C51—H51C	109.5
C8—C9—H9	120.4
C7—N1—C1—C6	178.4 (5)	C2—N2—C7—C8	−179.5 (5)
Pt1—N1—C1—C6	−2.8 (9)	C13—N2—C7—C8	−0.7 (8)
C7—N1—C1—C2	0.4 (5)	C12—N3—C8—C9	1.0 (7)
Pt1—N1—C1—C2	179.2 (4)	Pt1—N3—C8—C9	179.6 (4)
C7—N2—C2—C3	179.4 (5)	C12—N3—C8—C7	−178.6 (4)
C13—N2—C2—C3	0.6 (8)	Pt1—N3—C8—C7	0.0 (5)
C7—N2—C2—C1	−0.5 (5)	N1—C7—C8—N3	−0.2 (6)
C13—N2—C2—C1	−179.3 (4)	N2—C7—C8—N3	−180.0 (5)
C6—C1—C2—N2	−178.2 (4)	N1—C7—C8—C9	−179.8 (5)
N1—C1—C2—N2	0.1 (5)	N2—C7—C8—C9	0.5 (9)
C6—C1—C2—C3	1.9 (8)	N3—C8—C9—C10	−2.6 (8)
N1—C1—C2—C3	−179.9 (4)	C7—C8—C9—C10	177.0 (5)
N2—C2—C3—C4	177.6 (5)	C8—C9—C10—C11	2.0 (9)
C1—C2—C3—C4	−2.4 (8)	C9—C10—C11—C12	0.1 (9)
C2—C3—C4—C5	1.7 (8)	C8—N3—C12—C11	1.2 (8)
C2—C3—C4—C41	−178.1 (5)	Pt1—N3—C12—C11	−177.3 (4)
C3—C4—C5—C6	−0.5 (8)	C10—C11—C12—N3	−1.7 (8)
C41—C4—C5—C6	179.3 (5)	C7—N2—C13—C14	−67.0 (7)
C3—C4—C5—C51	−178.6 (5)	C2—N2—C13—C14	111.5 (5)
C41—C4—C5—C51	1.2 (8)	C18—N4—C14—C15	1.2 (9)
C2—C1—C6—C5	−0.6 (7)	C18—N4—C14—C13	−179.6 (6)
N1—C1—C6—C5	−178.4 (5)	N2—C13—C14—N4	−16.9 (7)
C4—C5—C6—C1	−0.1 (8)	N2—C13—C14—C15	162.4 (5)
C51—C5—C6—C1	178.0 (5)	N4—C14—C15—C16	−0.2 (10)
C1—N1—C7—N2	−0.7 (5)	C13—C14—C15—C16	−179.3 (6)
Pt1—N1—C7—N2	−179.8 (3)	C14—C15—C16—C17	−1.4 (11)
C1—N1—C7—C8	179.5 (4)	C15—C16—C17—C18	1.8 (11)
Pt1—N1—C7—C8	0.4 (5)	C14—N4—C18—C17	−0.8 (11)
C2—N2—C7—N1	0.8 (5)	C16—C17—C18—N4	−0.8 (12)
C13—N2—C7—N1	179.5 (4)

Hydrogen-bond geometry (Å, º)

Cg refers to the centroid of the five-membered platinum diimine ring.

D—H···A	D—H	H···A	D···A	D—H···A
C12—H12···Cl2	0.95	2.58	3.205 (6)	124
C10—H10···N4^i	0.95	2.59	3.388 (8)	142
C18—H18···Cl1^ii	0.95	2.76	3.546 (7)	140
C11—H11···Pt1^i	0.95	2.83	3.722 (6)	157
C11—H11···Cg^i	0.95	3.21	3.885 (6)	130
C13—H13A···Cl2^iii	0.99	2.80	3.564 (6)	135
C13—H13B···Cl1^iv	0.99	2.84	3.764 (6)	155

Symmetry codes: (i) x, −y+3/2, z−1/2; (ii) −x+1, y+1/2, −z+3/2; (iii) x−1, y, z; (iv) −x+1, −y+1, −z+1.