Crystal structure of [2,6-di­fluoro-3-(pyridin-2-yl-κN)pyridin-4-yl-κC ⁴](pentane-2,4-dionato-κ² O,O′)platinum(II)

The Pt^II atom adopts a distorted square-planar coordination geometry, being C,N-chelated by a 2′,6′-di­fluoro-2,3′-bi­pyridine ligand and O,O′-chelated by a pentane-2,4-dionato anionic ligand.

Abstract

The asymmetric unit of the title compound, [Pt(C₁₀H₅F₂N₂)(C₅H₇O₂)], comprises one Pt^II atom, one 2,6-di­fluoro-2,3-bi­pyridine ligand and one acetyl­acetonate anion. The Pt^II atom adopts a distorted square-planar coordination geometry, being C,N-chelated by the 2,6-di­fluoro-3-(pyridin-2-yl)pyridin-4-yl ligand and O,O′-chelated by the pentane-2,4-dionate ligand. The two pyridine rings of the bi­pyridine ligand are approximately coplanar, making a dihedral angle of 1.2 (2)°. A variety of intra- and inter­molecular C—H⋯O and C—H⋯F hydrogen bonds, as well as π–π inter­actions [centroid–centroid distances = 4.337 (3) and 3.774 (3) Å] contribute to the stabilization of the mol­ecular and crystal structures, and result in the formation of a three-dimensional supra­molecular framework.

Chemical context  

Cyclo­metalated platinum(II) compounds with C,N-chelating ligands have been considered as an attractive research area due to their wide applications, such as biological imaging, non-linear optics, oxygen sensing and organic light-emitting diodes (OLEDs) (Hudson et al., 2012 ▸). In particular, phenyl­pyridine (ppy) based platinum(II) β-diketonate compounds have been widely studied because of their excellent stability and high quantum efficiency in OLEDs (Rao et al., 2012 ▸). However, examples of platinum(II) compounds with C,N-chelating bi­pyridine ligands are scarce. Herein, we report the result of our investigation on the crystal structure of a novel platinum(II) compound with fluorinated bi­pyridine and acetyl­acetonate (acac, O,O) ligands.

Structural commentary  

The mol­ecular structure of the title compound is shown in Fig. 1 ▸. The asymmetric unit consists of one Pt^II atom, one 2,6-di­fluoro-2,3-bi­pyridine ligand and one acetyl­acetonate anion. The Pt^II atom is four-coordinated by the C,N-chelating 2′,6′-di­fluoro-2,3′-bipyridinato ligand and by the O,O′-chelating pentane-2,4-dionato ligand, forming a distorted square-planar coordination sphere due to narrow ligand bite angles, which range from 81.28 (17) to 93.25 (13)°. The Pt—C bond length of 1.951 (4) Å is shorter than the Pt—N bond length of 1.995 (4) Å due to the more electronegative fluorine substit­uent on the C-bound pyridine ring. The Pt—C, Pt—N and Pt—O bond lengths (Table 1 ▸) are in normal ranges as reported for similar Pt^II compounds, e.g. [Pt(Bppy)(acac)] (Bppy is a boron-functionalized phenyl­pyridine; Rao et al., 2012 ▸). Within the C,N-bidentate ligand of the title compound, the two pyridine rings are approximately co-planar, making a dihedral angle of 1.2 (2)°, indicating that an effective π conjugation of the two pyridine rings occurs in the title compound. The mol­ecular structure is stabilized by weak intra­molecular C—H⋯O and C—H⋯F hydrogen bonds (Table 2 ▸).

Figure 1.

View of the mol­ecular structure of the title compound, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level; dashed lines represent intra­molecular C—H⋯O and C—H⋯F hydrogen bonds.

Table 1. Selected bond lengths ().

Pt1C1	1.951(4)	Pt1O1	2.074(3)
Pt1N2	1.995(4)	Pt1O2	2.001(3)

Table 2. Hydrogen-bond geometry (, ).

DHA	DH	HA	D A	DHA
C2H2O2	0.95	2.57	3.040(5)	111
C7H7F2	0.95	2.31	2.917(6)	121
C10H10F1i	0.95	2.32	3.180(5)	150
C10H10O1	0.95	2.41	3.006(5)	120
C12H12F2ii	0.95	2.44	3.361(5)	163
C15H15AF1i	0.98	2.54	3.481(6)	161

Symmetry codes: (i) ; (ii) .

Supra­molecular features  

Inter­molecular C—H⋯F hydrogen bonds between neighboring mol­ecules lead to the formation of a two-dimensional supra­molecular network extending parallel to the (10) plane (Fig. 2 ▸, Table 2 ▸). These networks are inter­linked by π–π inter­actions [Cg1—Cg2ⁱ = 4.337 (3) Å and Cg1—Cg2ⁱⁱ = 3.774 (3) Å, where Cg1 and Cg2 are the centroids of the N1, C1–C5 and the N2, C6–C10 rings, respectively; symmetry codes: (i) −x + 1, −y + 2, −z + 2; (ii) −x + 2, −y + 2, −z + 2], resulting in the formation of an overall three-dimensional supra­molecular framework (Fig. 3 ▸).

Figure 2.

The two-dimensional supra­molecular network formed through C—H⋯F inter­actions (yellow dashed lines). H atoms not involved in inter­molecular inter­actions have been omitted for clarity.

Figure 3.

The three-dimensional supra­molecular network formed through π–π stacking inter­actions (black dashed lines). Yellow dashed lines indicate the C—H⋯F inter­actions. H atoms not involved in inter­molecular inter­actions have been omitted for clarity.

Synthesis and crystallization  

The title compound was synthesized according to a previous report (Rao et al., 2012 ▸). Slow evaporation from a di­chloro­methane/hexane solution afforded yellow crystals suitable for X-ray crystallography analysis.

Refinement  

Crystal data, data collection and crystal structure refinement details are summarized in Table 3 ▸. All H atoms were positioned geometrically and refined using a riding model, with d(C—H) = 0.95 Å, U _iso(H) = 1.2U _eq(C) for Csp ²-H, and 0.98 Å, U _iso(H) = 1.5U _eq(C) for methyl protons.

Table 3. Experimental details.

Crystal data
Chemical formula	[Pt(C10H5F2N2)(C5H7O2)]
M r	485.36
Crystal system, space group	Triclinic, P
Temperature (K)	180
a, b, c ()	8.0442(6), 9.8711(7), 10.1458(7)
, , ()	97.683(1), 112.320(1), 99.410(1)
V (3)	718.12(9)
Z	2
Radiation type	Mo K
(mm1)	9.80
Crystal size (mm)	0.27 0.24 0.12
Data collection
Diffractometer	Bruker APEXII CCD area detector
Absorption correction	Multi-scan (SADABS; Bruker, 2006 ▸)
T min, T max	0.177, 0.386
No. of measured, independent and observed [I > 2(I)] reflections	7062, 2810, 2773
R int	0.023
(sin /)max (1)	0.617
Refinement
R[F 2 > 2(F 2)], wR(F 2), S	0.017, 0.053, 1.07
No. of reflections	2810
No. of parameters	199
H-atom treatment	H-atom parameters constrained
max, min (e 3)	0.51, 1.27

Computer programs: APEX2 and SAINT (Bruker, 2006 ▸), SHELXS97, SHELXL97 and SHELXTL (Sheldrick, 2008 ▸) and DIAMOND (Brandenburg, 2005 ▸).

Supplementary Material

CCDC reference: 1051825

Additional supporting information: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Crystal data

[Pt(C10H5F2N2)(C5H7O2)]	Z = 2
Mr = 485.36	F(000) = 456
Triclinic, P1	Dx = 2.245 Mg m−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.0442 (6) Å	Cell parameters from 2773 reflections
b = 9.8711 (7) Å	θ = 2.1–26.0°
c = 10.1458 (7) Å	µ = 9.80 mm−1
α = 97.683 (1)°	T = 180 K
β = 112.320 (1)°	Block, yellow
γ = 99.410 (1)°	0.27 × 0.24 × 0.12 mm
V = 718.12 (9) Å3

Data collection

Bruker APEXII CCD area-detector diffractometer	2810 independent reflections
Radiation source: fine-focus sealed tube	2773 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.023
φ and ω scans	θmax = 26.0°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2006)	h = −9→9
Tmin = 0.177, Tmax = 0.386	k = −12→12
7062 measured reflections	l = −12→12

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)] = 0.017	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.053	H-atom parameters constrained
S = 1.07	w = 1/[σ2(Fo2) + (0.0295P)2 + 1.5655P] where P = (Fo2 + 2Fc2)/3
2810 reflections	(Δ/σ)max = 0.002
199 parameters	Δρmax = 0.51 e Å−3
0 restraints	Δρmin = −1.27 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	0.541428 (18)	0.778516 (13)	0.974446 (14)	0.01645 (7)
F1	0.6043 (5)	0.8519 (4)	0.4799 (3)	0.0462 (8)
F2	0.9252 (4)	1.1982 (3)	0.8748 (3)	0.0362 (6)
O1	0.4622 (4)	0.7037 (3)	1.1284 (3)	0.0240 (6)
O2	0.3730 (4)	0.6133 (3)	0.8158 (3)	0.0231 (6)
N1	0.7621 (5)	1.0252 (4)	0.6783 (4)	0.0294 (8)
N2	0.7143 (5)	0.9517 (4)	1.1169 (4)	0.0197 (7)
C1	0.6273 (6)	0.8664 (4)	0.8434 (5)	0.0209 (8)
C2	0.5731 (6)	0.8150 (5)	0.6931 (5)	0.0251 (8)
H2	0.4892	0.7267	0.6431	0.030*
C3	0.6477 (6)	0.8990 (5)	0.6230 (5)	0.0290 (9)
C4	0.8076 (6)	1.0704 (4)	0.8184 (5)	0.0245 (8)
C5	0.7490 (5)	0.9996 (4)	0.9079 (4)	0.0205 (8)
C6	0.7995 (6)	1.0466 (4)	1.0634 (5)	0.0210 (8)
C7	0.9196 (6)	1.1711 (4)	1.1559 (5)	0.0263 (9)
H7	0.9801	1.2372	1.1190	0.032*
C8	0.9507 (6)	1.1986 (5)	1.3023 (5)	0.0295 (9)
H8	1.0316	1.2836	1.3659	0.035*
C9	0.8626 (6)	1.1006 (5)	1.3545 (5)	0.0279 (9)
H9	0.8829	1.1168	1.4544	0.034*
C10	0.7447 (6)	0.9790 (5)	1.2585 (5)	0.0249 (8)
H10	0.6829	0.9121	1.2937	0.030*
C11	0.3374 (6)	0.5912 (4)	1.0981 (5)	0.0219 (8)
C12	0.2383 (6)	0.5027 (4)	0.9600 (5)	0.0247 (9)
H12	0.1450	0.4256	0.9525	0.030*
C13	0.2611 (6)	0.5149 (4)	0.8326 (5)	0.0230 (8)
C14	0.1488 (7)	0.4045 (5)	0.6953 (5)	0.0328 (10)
H14A	0.1816	0.4288	0.6163	0.049*
H14B	0.0170	0.3996	0.6684	0.049*
H14C	0.1746	0.3131	0.7117	0.049*
C15	0.3027 (7)	0.5529 (5)	1.2257 (5)	0.0305 (10)
H15A	0.3822	0.6245	1.3142	0.046*
H15B	0.3306	0.4613	1.2389	0.046*
H15C	0.1728	0.5479	1.2072	0.046*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Pt1	0.01828 (10)	0.01327 (9)	0.01850 (9)	0.00005 (6)	0.00925 (7)	0.00501 (6)
F1	0.062 (2)	0.0564 (19)	0.0253 (14)	0.0043 (16)	0.0257 (14)	0.0124 (13)
F2	0.0389 (15)	0.0238 (13)	0.0495 (17)	−0.0032 (11)	0.0244 (13)	0.0138 (12)
O1	0.0251 (15)	0.0198 (14)	0.0209 (14)	−0.0073 (12)	0.0087 (12)	0.0017 (11)
O2	0.0242 (14)	0.0179 (14)	0.0241 (14)	−0.0014 (11)	0.0095 (12)	0.0034 (11)
N1	0.031 (2)	0.033 (2)	0.034 (2)	0.0088 (16)	0.0200 (17)	0.0187 (17)
N2	0.0176 (16)	0.0169 (16)	0.0235 (17)	0.0015 (13)	0.0083 (14)	0.0045 (13)
C1	0.029 (2)	0.0176 (19)	0.025 (2)	0.0086 (16)	0.0169 (18)	0.0103 (16)
C2	0.027 (2)	0.025 (2)	0.022 (2)	0.0021 (17)	0.0101 (17)	0.0073 (16)
C3	0.032 (2)	0.037 (2)	0.021 (2)	0.0097 (19)	0.0124 (18)	0.0108 (18)
C4	0.023 (2)	0.021 (2)	0.035 (2)	0.0044 (16)	0.0161 (18)	0.0130 (17)
C5	0.0191 (18)	0.0190 (19)	0.025 (2)	0.0043 (15)	0.0102 (16)	0.0065 (16)
C6	0.0198 (18)	0.0182 (19)	0.028 (2)	0.0041 (15)	0.0119 (17)	0.0077 (16)
C7	0.023 (2)	0.0170 (19)	0.037 (2)	0.0004 (16)	0.0115 (18)	0.0070 (17)
C8	0.025 (2)	0.021 (2)	0.031 (2)	−0.0002 (17)	0.0042 (18)	−0.0021 (17)
C9	0.029 (2)	0.027 (2)	0.022 (2)	0.0038 (18)	0.0074 (17)	−0.0002 (17)
C10	0.028 (2)	0.024 (2)	0.023 (2)	0.0032 (17)	0.0120 (17)	0.0037 (16)
C11	0.023 (2)	0.020 (2)	0.028 (2)	0.0037 (16)	0.0136 (17)	0.0129 (16)
C12	0.021 (2)	0.0175 (19)	0.034 (2)	−0.0024 (16)	0.0119 (18)	0.0086 (17)
C13	0.0207 (19)	0.0160 (19)	0.027 (2)	−0.0004 (15)	0.0065 (17)	0.0040 (16)
C14	0.031 (2)	0.025 (2)	0.029 (2)	−0.0074 (18)	0.0057 (19)	−0.0023 (18)
C15	0.030 (2)	0.032 (2)	0.032 (2)	0.0008 (19)	0.016 (2)	0.0124 (19)

Geometric parameters (Å, º)

Pt1—C1	1.951 (4)	C7—C8	1.389 (7)
Pt1—N2	1.995 (4)	C7—H7	0.9500
Pt1—O1	2.074 (3)	C8—C9	1.384 (7)
Pt1—O2	2.001 (3)	C8—H8	0.9500
F1—C3	1.352 (5)	C9—C10	1.379 (6)
F2—C4	1.349 (5)	C9—H9	0.9500
O1—C11	1.282 (5)	C10—H10	0.9500
O2—C13	1.288 (5)	C11—C12	1.399 (6)
N1—C4	1.316 (6)	C11—C15	1.506 (6)
N1—C3	1.327 (6)	C12—C13	1.391 (6)
N2—C10	1.343 (5)	C12—H12	0.9500
N2—C6	1.361 (5)	C13—C14	1.504 (6)
C1—C5	1.406 (6)	C14—H14A	0.9800
C1—C2	1.410 (6)	C14—H14B	0.9800
C2—C3	1.368 (6)	C14—H14C	0.9800
C2—H2	0.9500	C15—H15A	0.9800
C4—C5	1.387 (6)	C15—H15B	0.9800
C5—C6	1.457 (6)	C15—H15C	0.9800
C6—C7	1.393 (6)
C1—Pt1—N2	81.28 (17)	C6—C7—H7	120.0
C1—Pt1—O2	92.90 (16)	C9—C8—C7	119.3 (4)
N2—Pt1—O2	174.15 (12)	C9—C8—H8	120.4
C1—Pt1—O1	174.40 (14)	C7—C8—H8	120.4
N2—Pt1—O1	93.25 (13)	C10—C9—C8	118.6 (4)
O2—Pt1—O1	92.55 (12)	C10—C9—H9	120.7
C11—O1—Pt1	123.4 (3)	C8—C9—H9	120.7
C13—O2—Pt1	123.9 (3)	N2—C10—C9	122.4 (4)
C4—N1—C3	113.8 (4)	N2—C10—H10	118.8
C10—N2—C6	119.9 (4)	C9—C10—H10	118.8
C10—N2—Pt1	123.4 (3)	O1—C11—C12	125.5 (4)
C6—N2—Pt1	116.7 (3)	O1—C11—C15	115.4 (4)
C5—C1—C2	117.9 (4)	C12—C11—C15	119.1 (4)
C5—C1—Pt1	114.5 (3)	C13—C12—C11	127.3 (4)
C2—C1—Pt1	127.4 (3)	C13—C12—H12	116.4
C3—C2—C1	116.6 (4)	C11—C12—H12	116.4
C3—C2—H2	121.7	O2—C13—C12	127.1 (4)
C1—C2—H2	121.7	O2—C13—C14	113.0 (4)
N1—C3—F1	113.5 (4)	C12—C13—C14	119.9 (4)
N1—C3—C2	127.9 (4)	C13—C14—H14A	109.5
F1—C3—C2	118.6 (4)	C13—C14—H14B	109.5
N1—C4—F2	113.7 (4)	H14A—C14—H14B	109.5
N1—C4—C5	126.6 (4)	C13—C14—H14C	109.5
F2—C4—C5	119.7 (4)	H14A—C14—H14C	109.5
C4—C5—C1	117.2 (4)	H14B—C14—H14C	109.5
C4—C5—C6	127.6 (4)	C11—C15—H15A	109.5
C1—C5—C6	115.3 (4)	C11—C15—H15B	109.5
N2—C6—C7	119.9 (4)	H15A—C15—H15B	109.5
N2—C6—C5	112.2 (4)	C11—C15—H15C	109.5
C7—C6—C5	128.0 (4)	H15A—C15—H15C	109.5
C8—C7—C6	119.9 (4)	H15B—C15—H15C	109.5
C8—C7—H7	120.0
N2—Pt1—O1—C11	176.1 (3)	C2—C1—C5—C6	180.0 (4)
O2—Pt1—O1—C11	−3.1 (3)	Pt1—C1—C5—C6	3.4 (5)
C1—Pt1—O2—C13	−175.2 (3)	C10—N2—C6—C7	0.7 (6)
O1—Pt1—O2—C13	3.5 (3)	Pt1—N2—C6—C7	178.9 (3)
C1—Pt1—N2—C10	−179.3 (4)	C10—N2—C6—C5	−179.6 (4)
O1—Pt1—N2—C10	1.9 (3)	Pt1—N2—C6—C5	−1.4 (4)
C1—Pt1—N2—C6	2.6 (3)	C4—C5—C6—N2	179.1 (4)
O1—Pt1—N2—C6	−176.2 (3)	C1—C5—C6—N2	−1.3 (5)
N2—Pt1—C1—C5	−3.2 (3)	C4—C5—C6—C7	−1.2 (7)
O2—Pt1—C1—C5	176.2 (3)	C1—C5—C6—C7	178.4 (4)
N2—Pt1—C1—C2	−179.4 (4)	N2—C6—C7—C8	−0.6 (6)
O2—Pt1—C1—C2	0.0 (4)	C5—C6—C7—C8	179.8 (4)
C5—C1—C2—C3	1.4 (6)	C6—C7—C8—C9	0.5 (6)
Pt1—C1—C2—C3	177.4 (3)	C7—C8—C9—C10	−0.6 (7)
C4—N1—C3—F1	−178.8 (4)	C6—N2—C10—C9	−0.8 (6)
C4—N1—C3—C2	0.9 (7)	Pt1—N2—C10—C9	−178.9 (3)
C1—C2—C3—N1	−1.8 (7)	C8—C9—C10—N2	0.8 (7)
C1—C2—C3—F1	177.9 (4)	Pt1—O1—C11—C12	0.5 (6)
C3—N1—C4—F2	179.4 (4)	Pt1—O1—C11—C15	178.7 (3)
C3—N1—C4—C5	0.3 (6)	O1—C11—C12—C13	3.4 (7)
N1—C4—C5—C1	−0.6 (6)	C15—C11—C12—C13	−174.8 (4)
F2—C4—C5—C1	−179.6 (4)	Pt1—O2—C13—C12	−1.3 (6)
N1—C4—C5—C6	179.1 (4)	Pt1—O2—C13—C14	179.2 (3)
F2—C4—C5—C6	0.0 (6)	C11—C12—C13—O2	−3.0 (7)
C2—C1—C5—C4	−0.3 (6)	C11—C12—C13—C14	176.4 (4)
Pt1—C1—C5—C4	−176.9 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O2	0.95	2.57	3.040 (5)	111
C7—H7···F2	0.95	2.31	2.917 (6)	121
C10—H10···F1i	0.95	2.32	3.180 (5)	150
C10—H10···O1	0.95	2.41	3.006 (5)	120
C12—H12···F2ii	0.95	2.44	3.361 (5)	163
C15—H15A···F1i	0.98	2.54	3.481 (6)	161

Symmetry codes: (i) x, y, z+1; (ii) x−1, y−1, z.