Bis[2-(1,3-benzo­thia­zol-2-yl)phenyl-κ2C1,N][1,3-bis­(4-bromo­phen­yl)propane-1,3-dionato-κ2O,O′]iridium(III)

Kim, Y.-I.; Yun, S.-J.; Kang, S.K.

doi:10.1107/S1600536813018394

metal-organic compounds

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Volume 69| Part 8| August 2013| Page m443

doi:10.1107/S1600536813018394

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Bis[2-(1,3-benzothiazol-2-yl)phenyl-κ²C¹,N][1,3-bis(4-bromophenyl)propane-1,3-dionato-κ²O,O′]iridium(III)

Young-Inn Kim,^a Seong-Jae Yun ^a and Sung Kwon Kang ^b ^*

^aDepartment of Chemistry Education and Interdisciplinary Program of Advanced Information and Display Materials, Pusan National University, Busan 609-735, Republic of Korea, and ^bDepartment of Chemistry, Chungnam National University, Daejeon 305-764, Republic of Korea
^*Correspondence e-mail: skkang@cnu.ac.kr

(Received 28 June 2013; accepted 3 July 2013; online 10 July 2013)

The title complex, [Ir(C₁₅H₉Br₂O₂)(C₁₃H₈NS)₂], lies about a crystallographic twofold rotation axis passing through the Ir^III atom and the central C atom of the bis(bromophenyl)propane-1,3-dionate ligand. The Ir^III atom adopts a distorted octahedral geometry coordinated by two N atoms in the axial positions, and two C and two O atoms in the equatorial plane. The dihedral angle between the two thiazole ring systems in the complex is 77.45 (10)°.

Related literature

For luminescent Ir complexes, see: Ulbricht et al. (2009 ); Liu et al. (2008 ); Hwang et al. (2005 ); Tsuboyama et al. (2003 ); Bera et al. (2007 ). For phosphorescent Ir complexes, see: Xu et al. (2009 ); Sengottuvelan et al. (2011 , 2013 ).

Experimental

Crystal data

[Ir(C₁₅H₉Br₂O₂)(C₁₃H₈NS)₂]
M_r = 993.77
Monoclinic, C 2/c
a = 15.888 (4) Å
b = 12.689 (3) Å
c = 17.143 (5) Å
β = 100.28 (5)°
V = 3400.8 (16) Å³
Z = 4
Mo Kα radiation
μ = 6.44 mm⁻¹
T = 203 K
0.35 × 0.29 × 0.16 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2002 ) T_min = 0.132, T_max = 0.365
15842 measured reflections
4079 independent reflections
3623 reflections with I > 2σ(I)
R_int = 0.059

Refinement

R[F² > 2σ(F²)] = 0.030
wR(F²) = 0.076
S = 1.06
4079 reflections
227 parameters
H-atom parameters constrained
Δρ_max = 1.55 e Å⁻³
Δρ_min = −1.26 e Å⁻³

Table 1
Selected bond lengths (Å)

Ir1—C18	1.996 (4)
Ir1—N12	2.060 (3)
Ir1—O2	2.155 (3)

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT; program(s) used to solve structure: SHELXS2013 (Sheldrick, 2013 ); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2013); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ); software used to prepare material for publication: WinGX (Farrugia, 2012).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536813018394/is5287sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813018394/is5287Isup2.hkl

checkCIF report

Comment top

Electrophosphorescent materials based on iridium(III) have been developed in order to apply for organic light-emitting diodes (OLEDs) (Ulbricht et al., 2009) because iridium(III) complexes possess relatively short excited state lifetimes, high quantum efficiencies (Liu et al., 2008; Hwang et al., 2005; Tsuboyama et al., 2003) and remarkable color tuning from red to blue by a modification of the ligand structures (Bera et al., 2007). Recently, we reported red phosphorescent iridium complexes (Sengottuvelan, Yun, Kim et al., 2013; Sengottuvelan et al., 2011) for an application for OLEDs. Herein, an orange-red emissive complex, a new heteroleptic cyclometalated iridium(III) complex containing two 2-phenylbenzothiazole as main ligands and 1,3-bis(p-bromophenyl)-1,3-propanedione as an ancillary ligand, is prepared and its crystal structure is reported. The title complex emitted at 617 (595 s h.) nm in dichloromethane at room temperature.

In the title compound (Fig. 1), the Ir^III atom lies on a twofold axis and is coordinated by two C atoms, two N atoms, and two O atoms of three bidentate ligands in a distorted octahedral geometry. The angles around Ir atoms are in the range of 79.67 (14)–97.27 (14)°. The Ir—C bond distances of 1.996 (4) Å are shorter than the Ir—N distances of 2.060 (3) Å due to the stronger trans influence of the phenyl ring compared to the 5-membered thiazole ring (Table 1). The bidentate 1,3-benzothiazol-2-ylphenyl ligand (N12–C26) is almost planar, with an r.m.s. deviation of 0.051 Å from the corresponding least-squares plane defined by the fifteen constituent atoms.

Related literature top

For luminescent Ir complexes, see: Ulbricht et al. (2009); Liu et al. (2008); Hwang et al. (2005); Tsuboyama et al. (2003); Bera et al. (2007). For phosphorescent Ir complexes, see: Xu et al. (2009); Sengottuvelan, Yun, Kim et al. (2013); Sengottuvelan et al. (2011).

Experimental top

2-Phenylbenzothiazole (pbt) was purchased from Sigma-Aldrich Chemicals.

Synthesis of 1,3-bis(p-bromophenyl)-1,3-propanedione (dbacac): A mixture of a sodium hydride in oil dispersion (60%) and ethyl 4-bromobenzoate in 20 ml of dry THF was heated to 60 °C. 4-Bromoacetophenone in 8 ml in dry THF was added dropwise to the mixture. After the reaction temperature was held at 60 °C for 1 day, the mixture was poured into water and then neutralized with hydrochloric acid. The resulting precipitate was recrystallized from dichloromethane and hexane to give pale ivory powders.

Synthesis of title complex: The reaction of IrCl₃ 3H₂O with pbt in a 3:1 mixture of 2-ethoxyethanol and water at 135 °C gave cyclometallated iridium(III) µ-chloro-bridged dimer, [(pbt)₂Ir(µ-Cl)]₂. The prepared iridium(III) dimer complex, sodium carbonate and dbacac were dissolved in 2-ethoxyethanol. The mixture was heated at 125 °C for 8 h. The mixture was extracted with dichloromethane and dried over anhydrous magnesium sulfate. The crude product was flash chromatographed on silica gel using dichloromethane/methanol as an eluent. The red crystals were obtained from hexane/chloroform solution by slow evaporation at room temperature.

Computing details top

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS2013 (Sheldrick, 2013); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2013); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top

Fig. 1. Molecular structure of the title compound, showing the atom-numbering scheme and 30% probability ellipsoids. [Symmetry code: (i) -x, y, -z + 1/2.]

Bis[2-(1,3-benzothiazol-2-yl)phenyl-κ²C¹,N][1,3-bis(4-bromophenyl)propane-1,3-dionato-κ²O,O']iridium(III) top

Crystal data top

[Ir(C₁₅H₉Br₂O₂)(C₁₃H₈NS)₂]	F(000) = 1920
M_r = 993.77	D_x = 1.941 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 6529 reflections
a = 15.888 (4) Å	θ = 2.3–28.2°
b = 12.689 (3) Å	µ = 6.44 mm⁻¹
c = 17.143 (5) Å	T = 203 K
β = 100.28 (5)°	Block, red
V = 3400.8 (16) Å³	0.35 × 0.29 × 0.16 mm
Z = 4

Data collection top

Bruker SMART CCD area-detector diffractometer	3623 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.059
ϕ and ω scans	θ_max = 28.3°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2002)	h = −9→21
T_min = 0.132, T_max = 0.365	k = −16→8
15842 measured reflections	l = −21→21
4079 independent reflections

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.030	H-atom parameters constrained
wR(F²) = 0.076	w = 1/[σ²(F_o²) + (0.0363P)² + 6.8133P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max = 0.001
4079 reflections	Δρ_max = 1.55 e Å⁻³
227 parameters	Δρ_min = −1.26 e Å⁻³

Crystal data top

[Ir(C₁₅H₉Br₂O₂)(C₁₃H₈NS)₂]	V = 3400.8 (16) Å³
M_r = 993.77	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 15.888 (4) Å	µ = 6.44 mm⁻¹
b = 12.689 (3) Å	T = 203 K
c = 17.143 (5) Å	0.35 × 0.29 × 0.16 mm
β = 100.28 (5)°

Data collection top

Bruker SMART CCD area-detector diffractometer	4079 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2002)	3623 reflections with I > 2σ(I)
T_min = 0.132, T_max = 0.365	R_int = 0.059
15842 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.030	0 restraints
wR(F²) = 0.076	H-atom parameters constrained
S = 1.06	Δρ_max = 1.55 e Å⁻³
4079 reflections	Δρ_min = −1.26 e Å⁻³
227 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Ir1	0	0.38790 (2)	0.25	0.01610 (7)
O2	0.02867 (16)	0.2664 (2)	0.33857 (15)	0.0201 (5)
C3	0.0262 (2)	0.1685 (3)	0.3239 (2)	0.0198 (7)
C4	0	0.1208 (4)	0.25	0.0307 (13)
H4	0	0.0475	0.25	0.037*
C5	0.0587 (2)	0.0971 (3)	0.3927 (2)	0.0206 (7)
C6	0.1155 (3)	0.1359 (3)	0.4576 (2)	0.0270 (8)
H6	0.1298	0.207	0.4595	0.032*
C7	0.1512 (3)	0.0701 (4)	0.5198 (3)	0.0311 (9)
H7	0.1909	0.0961	0.562	0.037*
C8	0.1264 (3)	−0.0348 (3)	0.5177 (3)	0.0290 (9)
C9	0.0688 (3)	−0.0745 (3)	0.4554 (2)	0.0265 (8)
H9	0.0528	−0.145	0.4547	0.032*
C10	0.0349 (3)	−0.0081 (3)	0.3935 (2)	0.0244 (8)
H10	−0.0047	−0.0346	0.3516	0.029*
Br11	0.17062 (3)	−0.12509 (4)	0.60339 (3)	0.04469 (14)
N12	0.11887 (19)	0.3940 (2)	0.21803 (19)	0.0202 (6)
C13	0.1968 (2)	0.3442 (3)	0.2459 (2)	0.0207 (7)
C14	0.2596 (2)	0.3667 (3)	0.1998 (2)	0.0244 (8)
S15	0.21858 (6)	0.45204 (9)	0.12315 (6)	0.0295 (2)
C16	0.1222 (2)	0.4541 (3)	0.1558 (2)	0.0199 (7)
C17	0.0476 (2)	0.5149 (3)	0.1241 (2)	0.0196 (7)
C18	−0.0208 (2)	0.4977 (3)	0.1654 (2)	0.0184 (7)
C19	−0.0952 (2)	0.5581 (3)	0.1394 (2)	0.0261 (8)
H19	−0.1418	0.5513	0.165	0.031*
C20	−0.0997 (3)	0.6271 (3)	0.0762 (3)	0.0303 (9)
H20	−0.1496	0.6655	0.0603	0.036*
C21	−0.0318 (3)	0.6408 (3)	0.0359 (2)	0.0268 (9)
H21	−0.0362	0.6875	−0.0064	0.032*
C22	0.0422 (2)	0.5837 (3)	0.0601 (2)	0.0228 (8)
H22	0.0883	0.5911	0.0337	0.027*
C23	0.2167 (2)	0.2787 (3)	0.3110 (2)	0.0268 (8)
H23	0.1763	0.2638	0.3425	0.032*
C24	0.2977 (3)	0.2359 (4)	0.3284 (3)	0.0333 (10)
H24	0.3115	0.1915	0.372	0.04*
C25	0.3590 (3)	0.2575 (4)	0.2825 (3)	0.0329 (10)
H25	0.413	0.2272	0.2954	0.039*
C26	0.3408 (3)	0.3236 (4)	0.2180 (3)	0.0327 (9)
H26	0.382	0.3388	0.1873	0.039*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ir1	0.01424 (10)	0.01535 (10)	0.01891 (12)	0	0.00346 (7)	0
O2	0.0234 (13)	0.0187 (13)	0.0190 (13)	−0.0013 (10)	0.0061 (10)	0.0028 (9)
C3	0.0209 (16)	0.0198 (18)	0.0201 (19)	−0.0006 (14)	0.0074 (14)	0.0040 (13)
C4	0.051 (4)	0.017 (3)	0.025 (3)	0	0.011 (3)	0
C5	0.0246 (18)	0.0197 (18)	0.0198 (19)	0.0025 (14)	0.0105 (14)	−0.0005 (13)
C6	0.0275 (19)	0.026 (2)	0.028 (2)	−0.0048 (16)	0.0062 (16)	0.0025 (15)
C7	0.0256 (19)	0.038 (2)	0.029 (2)	−0.0043 (18)	0.0026 (17)	0.0056 (17)
C8	0.0233 (18)	0.032 (2)	0.034 (2)	0.0048 (17)	0.0113 (17)	0.0138 (17)
C9	0.035 (2)	0.0183 (17)	0.029 (2)	0.0041 (16)	0.0139 (17)	0.0062 (15)
C10	0.0297 (19)	0.0208 (18)	0.024 (2)	−0.0005 (15)	0.0071 (16)	0.0023 (14)
Br11	0.0279 (2)	0.0540 (3)	0.0503 (3)	0.0050 (2)	0.0020 (2)	0.0296 (2)
N12	0.0169 (14)	0.0209 (15)	0.0228 (16)	0.0005 (12)	0.0034 (12)	−0.0015 (12)
C13	0.0143 (15)	0.0221 (18)	0.025 (2)	−0.0021 (14)	0.0016 (14)	−0.0042 (14)
C14	0.0207 (18)	0.025 (2)	0.028 (2)	0.0032 (15)	0.0063 (15)	0.0046 (14)
S15	0.0228 (5)	0.0371 (6)	0.0312 (6)	0.0040 (4)	0.0114 (4)	0.0114 (4)
C16	0.0198 (17)	0.0213 (17)	0.0185 (18)	−0.0025 (14)	0.0035 (14)	−0.0005 (13)
C17	0.0200 (17)	0.0193 (17)	0.0182 (18)	0.0002 (14)	0.0001 (14)	−0.0018 (13)
C18	0.0192 (16)	0.0154 (16)	0.0195 (19)	0.0010 (13)	0.0008 (14)	−0.0028 (12)
C19	0.0221 (18)	0.025 (2)	0.030 (2)	0.0033 (15)	0.0022 (16)	0.0000 (15)
C20	0.030 (2)	0.027 (2)	0.032 (2)	0.0094 (17)	0.0010 (17)	0.0011 (16)
C21	0.038 (2)	0.0191 (18)	0.022 (2)	−0.0004 (16)	0.0017 (17)	0.0013 (14)
C22	0.0251 (18)	0.0228 (18)	0.0200 (19)	−0.0028 (15)	0.0026 (15)	−0.0013 (14)
C23	0.0187 (17)	0.029 (2)	0.033 (2)	0.0008 (15)	0.0062 (16)	0.0096 (16)
C24	0.028 (2)	0.036 (2)	0.035 (2)	0.0082 (18)	0.0020 (18)	0.0116 (18)
C25	0.0216 (19)	0.035 (2)	0.041 (3)	0.0119 (17)	0.0036 (18)	0.0038 (18)
C26	0.0225 (19)	0.038 (2)	0.041 (3)	0.0040 (18)	0.0143 (17)	0.0054 (19)

Geometric parameters (Å, º) top

Ir1—C18ⁱ	1.996 (4)	C13—C23	1.382 (5)
Ir1—C18	1.996 (4)	C13—C14	1.407 (5)
Ir1—N12ⁱ	2.060 (3)	C14—C26	1.385 (5)
Ir1—N12	2.060 (3)	C14—S15	1.738 (4)
Ir1—O2ⁱ	2.155 (3)	S15—C16	1.722 (4)
Ir1—O2	2.155 (3)	C16—C17	1.436 (5)
O2—C3	1.266 (4)	C17—C22	1.394 (5)
C3—C4	1.399 (4)	C17—C18	1.415 (5)
C3—C5	1.505 (5)	C18—C19	1.413 (5)
C4—C3ⁱ	1.399 (4)	C19—C20	1.384 (6)
C4—H4	0.93	C19—H19	0.93
C5—C10	1.388 (5)	C20—C21	1.392 (6)
C5—C6	1.391 (6)	C20—H20	0.93
C6—C7	1.392 (6)	C21—C22	1.381 (6)
C6—H6	0.93	C21—H21	0.93
C7—C8	1.387 (6)	C22—H22	0.93
C7—H7	0.93	C23—C24	1.380 (5)
C8—C9	1.372 (6)	C23—H23	0.93
C8—Br11	1.896 (4)	C24—C25	1.384 (6)
C9—C10	1.386 (5)	C24—H24	0.93
C9—H9	0.93	C25—C26	1.377 (6)
C10—H10	0.93	C25—H25	0.93
N12—C16	1.320 (5)	C26—H26	0.93
N12—C13	1.396 (5)

C18ⁱ—Ir1—C18	91.4 (2)	C13—N12—Ir1	133.7 (3)
C18ⁱ—Ir1—N12ⁱ	79.67 (14)	C23—C13—N12	127.6 (3)
C18—Ir1—N12ⁱ	97.27 (14)	C23—C13—C14	119.5 (3)
C18ⁱ—Ir1—N12	97.27 (14)	N12—C13—C14	113.0 (3)
C18—Ir1—N12	79.67 (14)	C26—C14—C13	121.3 (4)
N12ⁱ—Ir1—N12	175.67 (17)	C26—C14—S15	128.7 (3)
C18ⁱ—Ir1—O2ⁱ	176.72 (12)	C13—C14—S15	110.1 (3)
C18—Ir1—O2ⁱ	90.04 (12)	C16—S15—C14	89.93 (18)
N12ⁱ—Ir1—O2ⁱ	97.24 (11)	N12—C16—C17	117.8 (3)
N12—Ir1—O2ⁱ	85.88 (11)	N12—C16—S15	114.8 (3)
C18ⁱ—Ir1—O2	90.04 (12)	C17—C16—S15	127.3 (3)
C18—Ir1—O2	176.72 (12)	C22—C17—C18	123.1 (3)
N12ⁱ—Ir1—O2	85.88 (11)	C22—C17—C16	124.4 (4)
N12—Ir1—O2	97.24 (11)	C18—C17—C16	112.5 (3)
O2ⁱ—Ir1—O2	88.63 (14)	C19—C18—C17	115.6 (3)
C3—O2—Ir1	124.5 (2)	C19—C18—Ir1	129.0 (3)
O2—C3—C4	126.8 (4)	C17—C18—Ir1	115.4 (3)
O2—C3—C5	116.2 (3)	C20—C19—C18	120.9 (4)
C4—C3—C5	117.0 (4)	C20—C19—H19	119.5
C3ⁱ—C4—C3	128.7 (5)	C18—C19—H19	119.5
C3ⁱ—C4—H4	115.7	C19—C20—C21	122.1 (4)
C3—C4—H4	115.7	C19—C20—H20	119
C10—C5—C6	118.1 (4)	C21—C20—H20	119
C10—C5—C3	122.1 (3)	C22—C21—C20	118.6 (4)
C6—C5—C3	119.8 (3)	C22—C21—H21	120.7
C5—C6—C7	121.2 (4)	C20—C21—H21	120.7
C5—C6—H6	119.4	C21—C22—C17	119.6 (4)
C7—C6—H6	119.4	C21—C22—H22	120.2
C8—C7—C6	118.7 (4)	C17—C22—H22	120.2
C8—C7—H7	120.7	C24—C23—C13	118.8 (4)
C6—C7—H7	120.7	C24—C23—H23	120.6
C9—C8—C7	121.3 (4)	C13—C23—H23	120.6
C9—C8—Br11	119.0 (3)	C23—C24—C25	121.5 (4)
C7—C8—Br11	119.7 (3)	C23—C24—H24	119.3
C8—C9—C10	119.1 (4)	C25—C24—H24	119.3
C8—C9—H9	120.4	C26—C25—C24	120.6 (4)
C10—C9—H9	120.4	C26—C25—H25	119.7
C9—C10—C5	121.5 (4)	C24—C25—H25	119.7
C9—C10—H10	119.2	C25—C26—C14	118.3 (4)
C5—C10—H10	119.2	C25—C26—H26	120.8
C16—N12—C13	112.2 (3)	C14—C26—H26	120.8
C16—N12—Ir1	114.0 (2)

Symmetry code: (i) −x, y, −z+1/2.

Experimental details

Crystal data
Chemical formula	[Ir(C₁₅H₉Br₂O₂)(C₁₃H₈NS)₂]
M_r	993.77
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	203
a, b, c (Å)	15.888 (4), 12.689 (3), 17.143 (5)
β (°)	100.28 (5)
V (Å³)	3400.8 (16)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	6.44
Crystal size (mm)	0.35 × 0.29 × 0.16

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2002)
T_min, T_max	0.132, 0.365
No. of measured, independent and observed [I > 2σ(I)] reflections	15842, 4079, 3623
R_int	0.059
(sin θ/λ)_max (Å⁻¹)	0.668

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.030, 0.076, 1.06
No. of reflections	4079
No. of parameters	227
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.55, −1.26

Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXS2013 (Sheldrick, 2013), SHELXL2013 (Sheldrick, 2013), ORTEP-3 for Windows (Farrugia, 2012), WinGX (Farrugia, 2012).

Selected bond lengths (Å) top

Ir1—C18	1.996 (4)	Ir1—O2	2.155 (3)
Ir1—N12	2.060 (3)

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