(Acetyl­acetonato-κ2O,O′)bis­{5-fluoro-2-[3-(4-fluoro­phen­yl)pyrazin-2-yl]phenyl-κ2N1,C1}iridium(III)

Ge, G.-P.; Li, C.-Y.

doi:10.1107/S1600536812031546

metal-organic compounds

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Volume 68| Part 8| August 2012| Page m1079

https://doi.org/10.1107/S1600536812031546

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(Acetylacetonato-κ²O,O′)bis{5-fluoro-2-[3-(4-fluorophenyl)pyrazin-2-yl]phenyl-κ²N¹,C¹}iridium(III)

Guo-Ping Ge ^a ^* and Chun-Yan Li ^a

^aState Key Laboratory Base of Novel Functional Materials and Preparation Science, Institute of Solid Materials Chemistry, Faculty of Materials Science and Chemical Engineering, Ningbo University, Ningbo 315211, People's Republic of China
^*Correspondence e-mail: geguoping@nbu.edu.cn

(Received 29 June 2012; accepted 11 July 2012; online 18 July 2012)

In the title complex, [Ir(C₁₆H₉F₂N₂)₂(C₅H₇O₂)], the Ir^III atom, lying on a twofold rotation axis, is hexacoordinated in a distorted octahedral geometry by two C,N-bidentate 5-fluoro-2-[3-(4-fluorophenyl)pyrazin-2-yl]phenyl ligands and one O,O′-bidentate acetylacetonate ligand. The dihedral angles between the benzene rings and the pyrazine ring are 14.66 (8) and 49.76 (12)°.

Related literature

For background to organic light-emitting diodes based on phosphorescent complexes, see: Baldo et al. (1998 , 2000 ). For the synthesis of the title compound, see: Ge et al. (2009 ).

Experimental

Crystal data

[Ir(C₁₆H₉F₂N₂)₂(C₅H₇O₂)]
M_r = 825.83
Monoclinic, C 2/c
a = 21.030 (4) Å
b = 10.010 (2) Å
c = 16.118 (3) Å
β = 105.58 (3)°
V = 3268.3 (12) Å³
Z = 4
Mo Kα radiation
μ = 4.15 mm⁻¹
T = 293 K
0.40 × 0.28 × 0.18 mm

Data collection

Rigaku R-AXIS RAPID diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ) T_min = 0.263, T_max = 0.470
14813 measured reflections
3714 independent reflections
3573 reflections with I > 2σ(I)
R_int = 0.074

Refinement

R[F² > 2σ(F²)] = 0.032
wR(F²) = 0.079
S = 1.03
3714 reflections
218 parameters
H-atom parameters constrained
Δρ_max = 2.15 e Å⁻³
Δρ_min = −2.10 e Å⁻³

Table 1
Selected bond lengths (Å)

Ir—C6	1.987 (3)
Ir—N1	2.009 (3)
Ir—O1	2.153 (2)

Data collection: RAPID-AUTO (Rigaku, 1998 ); cell refinement: RAPID-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2002 ); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536812031546/hy2570sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812031546/hy2570Isup2.hkl

checkCIF report

Comment top

Much attention has been paid to the phosphorescent materials in recent years for their potential applications as highly efficient electroluminescent (EL) emitters in organic light-emitting devices (OLEDs), since the first demonstration of highly efficient phosphorescent OLEDs with a maximum EQE of 4% were reported by Baldo et al. (1998, 2000). Among these phosphorescent complexes, iridium cyclometalates often exhibit favorable photoproperties for OLEDs including short phosphorescent lifetimes, high quantum efficiencies and good stability. Ge et al. (2009) demonstrated a high efficiency yellow OLED using [Ir(dppf)₂(acac)] [dppf = 2,3-di(4-fluorophenyl)pyrazine, acac = acetylacetone] as the dopant. In this work, we synthesized and investigated crystal structure of Ir(dppf)₂(acac).

The mononuclear title iridium(III) complex (Fig. 1) has an approximately octahedral coordination geometry. The Ir^III ion is hexacoordinated by two C atoms and two N atoms from two C,N-bidentate dppf ligands, which exhibit cis-C,C and trans-N,N chelate dispositions, and two O atoms from one O,O-bidentate acac ligand. The Ir—C, Ir—N and Ir—O bond lengths are listed in Table 1. Due to steric interactions, the phenyl groups are not coplanar with the pyrazine group. The dihedral angles are 14.66 (8)° between the N1,N2/C1–C4 and C5–C10 rings and 49.76 (12)° between the N1,N2/C1–C4 and C11–C16 rings.

Related literature top

For background to organic light-emitting diodes based on phosphorescent complexes, see: Baldo et al. (1998, 2000). For the synthesis of the title compound, see: Ge et al. (2009).

Experimental top

The title complex was obtained according to the procedure previously reported (Ge et al., 2009). Orange crystals of the title complex suitable for X-ray structure analysis were grown from a mixed solution of dichloromethane and ethanol (v/v, 1:3).

Structure description top

For background to organic light-emitting diodes based on phosphorescent complexes, see: Baldo et al. (1998, 2000). For the synthesis of the title compound, see: Ge et al. (2009).

Computing details top

Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO (Rigaku, 1998); data reduction: CrystalStructure (Rigaku/MSC, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of the title complex, showing displacement ellipsoids at the 30% probability level. [Symmetry code: (A) -x, y, -z+1/2.]

(Acetylacetonato-κ²O,O')bis{5-fluoro-2-[3-(4- fluorophenyl)pyrazin-2-yl]phenyl-κ²N¹,C¹}iridium(III) top

Crystal data top

[Ir(C₁₆H₉F₂N₂)₂(C₅H₇O₂)]	F(000) = 1616.0
M_r = 825.83	D_x = 1.678 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 3730 reflections
a = 21.030 (4) Å	θ = 3.3–27.4°
b = 10.010 (2) Å	µ = 4.15 mm⁻¹
c = 16.118 (3) Å	T = 293 K
β = 105.58 (3)°	Cylindric, orange
V = 3268.3 (12) Å³	0.40 × 0.28 × 0.18 mm
Z = 4

Data collection top

Rigaku R-AXIS RAPID diffractometer	3714 independent reflections
Radiation source: rotation anode	3573 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.074
ω scans	θ_max = 27.4°, θ_min = 3.3°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −27→27
T_min = 0.263, T_max = 0.470	k = −12→12
14813 measured reflections	l = −20→19

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)] = 0.032	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.079	H-atom parameters constrained
S = 1.03	w = 1/[σ²(F_o²) + (0.0468P)² + 2.1663P] where P = (F_o² + 2F_c²)/3
3714 reflections	(Δ/σ)_max = 0.001
218 parameters	Δρ_max = 2.15 e Å⁻³
0 restraints	Δρ_min = −2.10 e Å⁻³

Crystal data top

[Ir(C₁₆H₉F₂N₂)₂(C₅H₇O₂)]	V = 3268.3 (12) Å³
M_r = 825.83	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 21.030 (4) Å	µ = 4.15 mm⁻¹
b = 10.010 (2) Å	T = 293 K
c = 16.118 (3) Å	0.40 × 0.28 × 0.18 mm
β = 105.58 (3)°

Data collection top

Rigaku R-AXIS RAPID diffractometer	3714 independent reflections
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	3573 reflections with I > 2σ(I)
T_min = 0.263, T_max = 0.470	R_int = 0.074
14813 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.032	0 restraints
wR(F²) = 0.079	H-atom parameters constrained
S = 1.03	Δρ_max = 2.15 e Å⁻³
3714 reflections	Δρ_min = −2.10 e Å⁻³
218 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
Ir	0.0000	0.399077 (13)	0.2500	0.02715 (8)
N1	−0.08587 (17)	0.4046 (2)	0.1576 (2)	0.0322 (6)
N2	−0.20277 (17)	0.4187 (3)	0.0278 (2)	0.0438 (8)
F1	0.15157 (10)	0.7392 (3)	0.12655 (16)	0.0565 (6)
F2	−0.2418 (2)	0.9357 (4)	−0.1927 (3)	0.0993 (12)
C1	−0.13642 (17)	0.3191 (3)	0.1545 (2)	0.0403 (7)
H2A	−0.1330	0.2571	0.1985	0.048*
C2	−0.19232 (18)	0.3227 (4)	0.0876 (3)	0.0491 (9)
H1A	−0.2240	0.2565	0.0836	0.059*
C3	−0.15473 (15)	0.5090 (3)	0.03242 (19)	0.0340 (6)
C4	−0.09249 (14)	0.4969 (3)	0.09367 (18)	0.0294 (6)
C5	−0.03044 (15)	0.5686 (3)	0.0989 (2)	0.0287 (6)
C6	0.02113 (15)	0.5378 (3)	0.1734 (2)	0.0286 (6)
C7	0.0829 (2)	0.5995 (3)	0.1821 (3)	0.0360 (8)
H25A	0.1175	0.5854	0.2311	0.043*
C8	0.09109 (16)	0.6806 (3)	0.1172 (2)	0.0377 (7)
C9	0.04288 (16)	0.7039 (3)	0.0422 (2)	0.0362 (6)
H16A	0.0514	0.7559	−0.0014	0.043*
C10	−0.01820 (16)	0.6482 (3)	0.0333 (2)	0.0326 (6)
H15A	−0.0518	0.6634	−0.0167	0.039*
C11	−0.17425 (18)	0.6233 (4)	−0.0285 (3)	0.0375 (8)
C12	−0.16476 (17)	0.7527 (4)	0.0010 (2)	0.0439 (8)
H14A	−0.1429	0.7691	0.0583	0.053*
C13	−0.1875 (2)	0.8589 (5)	−0.0543 (3)	0.0549 (10)
H12A	−0.1811	0.9467	−0.0350	0.066*
C14	−0.2196 (2)	0.8303 (5)	−0.1381 (3)	0.0632 (12)
C15	−0.2303 (2)	0.7040 (5)	−0.1699 (3)	0.0624 (12)
H13A	−0.2524	0.6887	−0.2273	0.075*
C16	−0.2074 (2)	0.5988 (4)	−0.1142 (3)	0.0492 (11)
H3A	−0.2141	0.5114	−0.1341	0.059*
C17	0.0240 (2)	0.1210 (4)	0.1865 (3)	0.0475 (10)
C18	0.0470 (3)	0.0333 (5)	0.1240 (4)	0.0766 (15)
H21A	0.0621	0.0883	0.0844	0.115*
H21B	0.0110	−0.0214	0.0928	0.115*
H21C	0.0825	−0.0227	0.1552	0.115*
C19	0.0000	0.0599 (6)	0.2500	0.0603 (16)
H22A	0.0000	−0.0330	0.2500	0.072*
O1	0.02969 (13)	0.2442 (3)	0.17557 (16)	0.0398 (5)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ir	0.02894 (11)	0.02803 (11)	0.02172 (11)	0.000	0.00204 (7)	0.000
N1	0.0352 (15)	0.0325 (15)	0.0286 (14)	−0.0030 (9)	0.0080 (13)	−0.0008 (9)
N2	0.0350 (16)	0.0511 (18)	0.0377 (17)	−0.0084 (12)	−0.0036 (14)	0.0000 (13)
F1	0.0401 (11)	0.0654 (15)	0.0638 (14)	−0.0176 (10)	0.0139 (11)	0.0071 (12)
F2	0.110 (3)	0.087 (2)	0.088 (3)	0.024 (2)	0.003 (2)	0.051 (2)
C1	0.0406 (17)	0.0391 (18)	0.0378 (16)	−0.0104 (13)	0.0042 (14)	0.0021 (13)
C2	0.0415 (18)	0.050 (2)	0.049 (2)	−0.0167 (15)	−0.0011 (17)	0.0013 (16)
C3	0.0318 (14)	0.0389 (16)	0.0276 (14)	0.0016 (12)	0.0017 (12)	−0.0027 (13)
C4	0.0318 (13)	0.0324 (14)	0.0222 (12)	0.0016 (11)	0.0039 (11)	−0.0037 (11)
C5	0.0310 (14)	0.0284 (13)	0.0251 (14)	0.0024 (12)	0.0050 (12)	−0.0018 (12)
C6	0.0295 (14)	0.0272 (15)	0.0271 (14)	0.0021 (11)	0.0040 (12)	−0.0020 (11)
C7	0.0309 (17)	0.040 (2)	0.0333 (19)	−0.0029 (11)	0.0015 (16)	−0.0009 (11)
C8	0.0329 (15)	0.0367 (17)	0.0448 (17)	−0.0054 (12)	0.0129 (14)	−0.0034 (14)
C9	0.0424 (16)	0.0335 (15)	0.0364 (16)	−0.0001 (13)	0.0172 (14)	0.0005 (13)
C10	0.0358 (15)	0.0352 (16)	0.0258 (14)	0.0043 (13)	0.0062 (12)	0.0009 (13)
C11	0.0304 (16)	0.0477 (19)	0.0318 (18)	0.0044 (13)	0.0036 (14)	0.0022 (14)
C12	0.0367 (17)	0.050 (2)	0.0428 (19)	0.0119 (15)	0.0071 (15)	0.0030 (16)
C13	0.047 (2)	0.047 (2)	0.069 (3)	0.0087 (18)	0.013 (2)	0.009 (2)
C14	0.057 (2)	0.071 (3)	0.059 (3)	0.019 (2)	0.010 (2)	0.029 (2)
C15	0.058 (2)	0.081 (3)	0.0391 (19)	0.012 (2)	−0.0029 (19)	0.012 (2)
C16	0.044 (2)	0.061 (3)	0.037 (2)	0.0067 (14)	0.001 (2)	0.0027 (14)
C17	0.055 (2)	0.0367 (19)	0.050 (2)	0.0042 (15)	0.012 (2)	−0.0064 (16)
C18	0.118 (4)	0.046 (3)	0.076 (3)	0.009 (3)	0.044 (3)	−0.011 (2)
C19	0.094 (5)	0.026 (2)	0.065 (4)	0.000	0.029 (4)	0.000
O1	0.0494 (14)	0.0366 (13)	0.0322 (12)	0.0021 (10)	0.0087 (11)	−0.0069 (10)

Geometric parameters (Å, º) top

Ir—C6	1.987 (3)	C9—C10	1.372 (5)
Ir—N1	2.009 (3)	C9—H16A	0.9300
Ir—O1	2.153 (2)	C10—H15A	0.9300
N1—C4	1.363 (4)	C11—C12	1.375 (6)
N1—C1	1.356 (4)	C11—C16	1.392 (6)
N2—C3	1.342 (5)	C12—C13	1.387 (6)
N2—C2	1.337 (5)	C12—H14A	0.9300
F1—C8	1.372 (4)	C13—C14	1.369 (7)
F2—C14	1.373 (5)	C13—H12A	0.9300
C1—C2	1.366 (5)	C14—C15	1.360 (7)
C1—H2A	0.9300	C15—C16	1.384 (6)
C2—H1A	0.9300	C15—H13A	0.9300
C3—C4	1.417 (4)	C16—H3A	0.9300
C3—C11	1.492 (5)	C17—O1	1.256 (5)
C4—C5	1.472 (4)	C17—C19	1.399 (6)
C5—C10	1.403 (5)	C17—C18	1.509 (6)
C5—C6	1.418 (4)	C18—H21A	0.9600
C6—C7	1.411 (5)	C18—H21B	0.9600
C7—C8	1.371 (5)	C18—H21C	0.9600
C7—H25A	0.9300	C19—C17ⁱ	1.399 (6)
C8—C9	1.374 (5)	C19—H22A	0.9300

C6ⁱ—Ir—C6	91.30 (18)	F1—C8—C7	118.2 (3)
C6ⁱ—Ir—N1	97.75 (12)	F1—C8—C9	117.9 (3)
C6—Ir—N1	80.01 (12)	C7—C8—C9	123.9 (3)
C6ⁱ—Ir—N1ⁱ	80.01 (12)	C10—C9—C8	118.2 (3)
C6—Ir—N1ⁱ	97.75 (12)	C10—C9—H16A	120.9
N1—Ir—N1ⁱ	176.82 (13)	C8—C9—H16A	120.9
C6ⁱ—Ir—O1	175.30 (9)	C9—C10—C5	120.5 (3)
C6—Ir—O1	90.58 (13)	C9—C10—H15A	119.7
N1—Ir—O1	86.82 (11)	C5—C10—H15A	119.7
N1ⁱ—Ir—O1	95.48 (11)	C12—C11—C16	119.7 (3)
C6ⁱ—Ir—O1ⁱ	90.58 (13)	C12—C11—C3	120.5 (3)
C6—Ir—O1ⁱ	175.30 (9)	C16—C11—C3	119.6 (3)
N1—Ir—O1ⁱ	95.48 (11)	C11—C12—C13	120.5 (4)
N1ⁱ—Ir—O1ⁱ	86.82 (11)	C11—C12—H14A	119.8
O1—Ir—O1ⁱ	87.88 (15)	C13—C12—H14A	119.8
C4—N1—C1	118.7 (3)	C14—C13—C12	117.9 (5)
C4—N1—Ir	117.9 (2)	C14—C13—H12A	121.1
C1—N1—Ir	123.3 (2)	C12—C13—H12A	121.1
C3—N2—C2	117.9 (3)	C13—C14—C15	123.6 (4)
N1—C1—C2	120.8 (3)	C13—C14—F2	117.7 (5)
N1—C1—H2A	119.6	C15—C14—F2	118.7 (5)
C2—C1—H2A	119.6	C14—C15—C16	118.0 (4)
N2—C2—C1	121.9 (3)	C14—C15—H13A	121.0
N2—C2—H1A	119.0	C16—C15—H13A	121.0
C1—C2—H1A	119.0	C15—C16—C11	120.3 (4)
N2—C3—C4	121.5 (3)	C15—C16—H3A	119.9
N2—C3—C11	114.2 (3)	C11—C16—H3A	119.9
C4—C3—C11	124.3 (3)	O1—C17—C19	126.8 (4)
N1—C4—C3	118.2 (3)	O1—C17—C18	114.7 (4)
N1—C4—C5	112.2 (3)	C19—C17—C18	118.5 (4)
C3—C4—C5	129.6 (3)	C17—C18—H21A	109.5
C10—C5—C6	120.5 (3)	C17—C18—H21B	109.5
C10—C5—C4	125.0 (3)	H21A—C18—H21B	109.5
C6—C5—C4	114.0 (3)	C17—C18—H21C	109.5
C7—C6—C5	117.6 (3)	H21A—C18—H21C	109.5
C7—C6—Ir	126.7 (2)	H21B—C18—H21C	109.5
C5—C6—Ir	115.5 (2)	C17ⁱ—C19—C17	128.1 (6)
C8—C7—C6	118.9 (3)	C17ⁱ—C19—H22A	115.9
C8—C7—H25A	120.6	C17—C19—H22A	115.9
C6—C7—H25A	120.6	C17—O1—Ir	125.2 (3)

Symmetry code: (i) −x, y, −z+1/2.

Experimental details

Crystal data
Chemical formula	[Ir(C₁₆H₉F₂N₂)₂(C₅H₇O₂)]
M_r	825.83
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	293
a, b, c (Å)	21.030 (4), 10.010 (2), 16.118 (3)
β (°)	105.58 (3)
V (Å³)	3268.3 (12)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	4.15
Crystal size (mm)	0.40 × 0.28 × 0.18

Data collection
Diffractometer	Rigaku R-AXIS RAPID
Absorption correction	Multi-scan (ABSCOR; Higashi, 1995)
T_min, T_max	0.263, 0.470
No. of measured, independent and observed [I > 2σ(I)] reflections	14813, 3714, 3573
R_int	0.074
(sin θ/λ)_max (Å⁻¹)	0.648

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.032, 0.079, 1.03
No. of reflections	3714
No. of parameters	218
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	2.15, −2.10

Computer programs: RAPID-AUTO (Rigaku, 1998), CrystalStructure (Rigaku/MSC, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top

Ir—C6	1.987 (3)	Ir—O1	2.153 (2)
Ir—N1	2.009 (3)

Acknowledgements

This project was supported by the Ningbo Municipal Natural Science Foundation (grant No. 2010A610164) and the Scientific Research Fund of Ningbo University (grant No. XKL073). Grateful thanks are also extended to the K. C. Wong Magna Fund of Ningbo University.

References

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