{4-[5-(4-tert-Butyl­phen­yl)-1,3,4-oxa­diazol-2-yl]phen­yl}methanol

Zhao, Y.-L.; Lv, Z.; Tian, B.; Hou, Z.; Geng, Z.-R.

doi:10.1107/S1600536810052967

organic compounds

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ISSN: 2056-9890

Volume 67| Part 2| February 2011| Page o251

doi:10.1107/S1600536810052967

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{4-[5-(4-tert-Butylphenyl)-1,3,4-oxadiazol-2-yl]phenyl}methanol

Yu-Ling Zhao,^a ^* Zhe Lv,^a Bin Tian,^a Zhe Hou ^a and Zhong-Rong Geng ^b

^aSchool of Chemical and Biological Engineering, Lanzhou Jiaotong University, Lanzhou 730070, People's Republic of China, and ^bKey Laboratory of Opto-Electronic Technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong University, Lanzhou 730070, People's Republic of China
^*Correspondence e-mail: zhaoyl66@hotmail.com

(Received 2 December 2010; accepted 16 December 2010; online 8 January 2011)

In the title compound, C₁₉H₂₀N₂O₂, the 1,3,4-oxadiazole ring is almost coplanar with the two neighboring benzene rings [dihedral angles = 3.76 (4) and 5.49 (4)°]. In the crystal, molecules are connected by strong intermolecular O—H⋯N hydrogen bonds, forming chains parallel to the c axis.

Related literature

For the properties and applications of 1,3,4-oxadiazole derivatives, see: Hughes & Bryce (2005 ); Kim & Lee (2007 ); Kulkarni et al. (2004 ); Liang et al. (2003 ); Liou et al. (2006 ); Strukelj et al. (1995 ). For the biological activity of compounds containing the 1,3,4-oxadiazole moiety, see: Cacic et al. (2006 ); Mansour et al. (2003 ); Yar et al. (2007 ); Zhang et al. (2007 ). For synthesis of the intermediate, see Mashraqui et al. (2007 ).

Experimental

Crystal data

C₁₉H₂₀N₂O₂
M_r = 308.37
Monoclinic, P 2₁ /c
a = 16.3958 (18) Å
b = 6.0654 (7) Å
c = 16.7206 (19) Å
β = 102.289 (2)°
V = 1624.7 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 185 K
0.32 × 0.14 × 0.09 mm

Data collection

Bruker SMART APEX CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.974, T_max = 0.993
8995 measured reflections
2886 independent reflections
1805 reflections with I > 2σ(I)
R_int = 0.051

Refinement

R[F² > 2σ(F²)] = 0.049
wR(F²) = 0.122
S = 0.98
2886 reflections
212 parameters
H-atom parameters constrained
Δρ_max = 0.16 e Å⁻³
Δρ_min = −0.14 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N2ⁱ	0.84	2.07	2.906 (3)	179
Symmetry code: (i) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: SMART (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810052967/pk2290sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810052967/pk2290Isup2.hkl

checkCIF report

Comment top

It is well known that 1,3,4-oxadiazole derivatives have strong electron affinity and possess electron-transporting characteristics. They have been widely used as electroluminescent materials and as electron-transport materials in organic light-emitting diodes (OLEDs) (Strukelj et al., 1995; Kulkarni et al., 2004; Hughes & Bryce 2005). Due to its excellent electron transporting properties, the 1,3,4-oxadiazole unit has been embedded in larger compounds to improve the quantum efficiencies of OLEDs (Liang et al., 2003; Liou et al., 2006; Kim & Lee 2007). Moreover, the compounds containing 1,3,4-oxadiazole also exhibit beneficial biological activity, such as anti-inflammatory, antibacterial, anticancer, plant growth regulation, weed and worm killing, anti-HIV and other activities (Cacic et al., 2006; Mansour et al., 2003; Zhang et al., 2007; Yar et al., 2007).

The molecular structure of the title compound is shown in Fig.1. Bond lengths and angles in the molecule are within normal ranges. The 1,3,4-oxadiazole ring is almost coplanar with two neighboring benzene rings (dihedral angles between the 1,3,4-oxadiazole ring and two benzene rings are 3.76 (4)° and 5.49 (4)°. The crystal structure is stabilized by intermolecular O—H···N hydrogen bonds (Fig. 2), to form chains parallel to the c axis.

Related literature top

For the properties and applications of 1,3,4-oxadiazole derivatives, see: Hughes & Bryce (2005); Kim & Lee (2007); Kulkarni et al. (2004); Liang et al. (2003); Liou et al. (2006); Strukelj et al. (1995). For the biological activity of compounds containing the 1,3,4-oxadiazole moiety, see: Cacic et al. (2006); Mansour et al. (2003); Yar et al. (2007); Zhang et al. (2007). For synthesis of the intermediate, see Mashraqui et al. (2007).

Experimental top

The title compound was obtained by reacting 2-[4-(bromomethyl)phenyl]-5-(4-tert-butylphenyl)-1,3,4-oxadiazole and potassium hydroxide in N,N-dimethyllformamide. The intermediate, 2-[4-(bromomethyl)phenyl]-5-(4-tert-butylphenyl)-1,3,4-oxadiazole, was synthesized according to the method described by Mashraqui et al. (Mashraqui et al., 2007).

After dispersing potassium hydroxide (3.62 mmol) in N,N-dimethylformamide (30 ml) for 10 min, 2-[4-(bromomethyl)phenyl]-5-(4-tert-butylphenyl)- 1,3,4-oxadiazole (3.62 mmol) was added. The reaction vessel was refluxed for one day. Neutralization with saturated aqueous ammonium chloride (100 ml) followed by extraction with dichloromethane (100 ml) was performed, and the organic layer was dried over anhydrous magnesium sulfate. The concentrated crude product was purified with silica column chromatography to afford the title compound. m.p. 381–383 K. ¹H-NMR (500 MHz, CDCl₃): 8.12–8.05 (m, 4H, Ar—H), 7.56–7.52 (m, 4H, Ar—H), 4.81 (s, 2H, –CH₂–), 2.31 (s, 1H, –OH), 1.41 (s, 9H, –CH₃).

Colourless single crystals were obtained by slow evaporation of a methanolic solution at room temperature.

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecule structure of the title compound. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 2. Packing diagram of the title compound showing the bc plane. Intermolecular O—H···N hydrogen bonds (dashed lines) form chains parallel to the c axis

{4-[5-(4-tert-Butylphenyl)-1,3,4-oxadiazol-2-yl]phenyl}methanol top

Crystal data top

C₁₉H₂₀N₂O₂	F(000) = 656
M_r = 308.37	D_x = 1.261 Mg m⁻³
Monoclinic, P2₁/c	Melting point = 381–383 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 16.3958 (18) Å	Cell parameters from 1372 reflections
b = 6.0654 (7) Å	θ = 2.5–23.3°
c = 16.7206 (19) Å	µ = 0.08 mm⁻¹
β = 102.289 (2)°	T = 185 K
V = 1624.7 (3) Å³	Block, colorless
Z = 4	0.32 × 0.14 × 0.09 mm

Data collection top

Bruker SMART APEX CCD diffractometer	2886 independent reflections
Radiation source: sealed tube	1805 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.051
ϕ and ω scans	θ_max = 25.1°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −14→19
T_min = 0.974, T_max = 0.993	k = −7→7
8995 measured reflections	l = −19→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)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.122	H-atom parameters constrained
S = 0.98	w = 1/[σ²(F_o²) + (0.0608P)²] where P = (F_o² + 2F_c²)/3
2886 reflections	(Δ/σ)_max < 0.001
212 parameters	Δρ_max = 0.16 e Å⁻³
0 restraints	Δρ_min = −0.14 e Å⁻³

Crystal data top

C₁₉H₂₀N₂O₂	V = 1624.7 (3) Å³
M_r = 308.37	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 16.3958 (18) Å	µ = 0.08 mm⁻¹
b = 6.0654 (7) Å	T = 185 K
c = 16.7206 (19) Å	0.32 × 0.14 × 0.09 mm
β = 102.289 (2)°

Data collection top

Bruker SMART APEX CCD diffractometer	2886 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	1805 reflections with I > 2σ(I)
T_min = 0.974, T_max = 0.993	R_int = 0.051
8995 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.049	0 restraints
wR(F²) = 0.122	H-atom parameters constrained
S = 0.98	Δρ_max = 0.16 e Å⁻³
2886 reflections	Δρ_min = −0.14 e Å⁻³
212 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
O1	0.11403 (11)	−0.3479 (3)	0.77257 (10)	0.0481 (5)
H1	0.1306	−0.2304	0.7974	0.072*
O2	0.21110 (9)	0.1173 (2)	0.41106 (9)	0.0363 (4)
N1	0.12828 (12)	0.3966 (3)	0.42308 (11)	0.0396 (5)
N2	0.16872 (13)	0.4399 (3)	0.35861 (11)	0.0405 (5)
C1	0.04959 (16)	−0.2996 (4)	0.70351 (14)	0.0423 (6)
H1A	0.0045	−0.2187	0.7219	0.051*
H1B	0.0259	−0.4397	0.6784	0.051*
C2	0.07960 (15)	−0.1632 (4)	0.63943 (13)	0.0358 (6)
C3	0.13751 (15)	−0.2496 (4)	0.59808 (14)	0.0388 (6)
H3	0.1603	−0.3919	0.6119	0.047*
C4	0.16207 (15)	−0.1294 (4)	0.53697 (13)	0.0375 (6)
H4	0.2006	−0.1915	0.5081	0.045*
C5	0.13098 (15)	0.0811 (3)	0.51743 (13)	0.0334 (6)
C6	0.07323 (15)	0.1692 (4)	0.55888 (13)	0.0373 (6)
H6	0.0512	0.3127	0.5458	0.045*
C7	0.04808 (15)	0.0471 (4)	0.61911 (13)	0.0386 (6)
H7	0.0086	0.1077	0.6471	0.046*
C8	0.15439 (14)	0.2058 (4)	0.45132 (13)	0.0335 (6)
C9	0.21555 (15)	0.2722 (4)	0.35340 (13)	0.0346 (6)
C10	0.26874 (14)	0.2326 (4)	0.29488 (13)	0.0338 (6)
C11	0.30966 (17)	0.0348 (4)	0.29253 (16)	0.0514 (7)
H11	0.3055	−0.0775	0.3311	0.062*
C12	0.35681 (17)	−0.0006 (4)	0.23410 (16)	0.0546 (8)
H12	0.3847	−0.1377	0.2336	0.066*
C13	0.36454 (15)	0.1577 (4)	0.17643 (14)	0.0366 (6)
C14	0.32332 (15)	0.3538 (4)	0.18029 (14)	0.0422 (6)
H14	0.3276	0.4666	0.1420	0.051*
C15	0.27591 (15)	0.3921 (4)	0.23804 (14)	0.0424 (6)
H15	0.2481	0.5293	0.2386	0.051*
C16	0.41390 (15)	0.1098 (4)	0.10994 (14)	0.0393 (6)
C17	0.49387 (17)	−0.0160 (5)	0.14583 (17)	0.0589 (8)
H17A	0.5287	0.0726	0.1890	0.088*
H17B	0.5245	−0.0455	0.1026	0.088*
H17C	0.4798	−0.1559	0.1689	0.088*
C18	0.4366 (2)	0.3210 (4)	0.06978 (19)	0.0703 (10)
H18A	0.4693	0.4174	0.1117	0.105*
H18B	0.3854	0.3971	0.0427	0.105*
H18C	0.4696	0.2839	0.0292	0.105*
C19	0.35905 (17)	−0.0327 (4)	0.04458 (15)	0.0532 (7)
H19A	0.3890	−0.0653	0.0011	0.080*
H19B	0.3074	0.0466	0.0214	0.080*
H19C	0.3456	−0.1708	0.0693	0.080*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0561 (13)	0.0525 (10)	0.0353 (10)	−0.0063 (9)	0.0085 (9)	0.0032 (8)
O2	0.0408 (11)	0.0420 (9)	0.0285 (9)	0.0023 (7)	0.0127 (8)	0.0020 (7)
N1	0.0450 (14)	0.0458 (12)	0.0301 (11)	0.0014 (10)	0.0128 (10)	0.0014 (9)
N2	0.0427 (13)	0.0494 (12)	0.0323 (12)	0.0062 (10)	0.0144 (10)	0.0039 (9)
C1	0.0477 (18)	0.0502 (15)	0.0292 (14)	−0.0063 (12)	0.0088 (13)	−0.0010 (11)
C2	0.0388 (16)	0.0416 (14)	0.0275 (13)	−0.0080 (11)	0.0084 (11)	−0.0043 (10)
C3	0.0436 (16)	0.0367 (13)	0.0373 (14)	−0.0020 (11)	0.0114 (13)	−0.0019 (11)
C4	0.0393 (16)	0.0422 (13)	0.0340 (13)	−0.0038 (11)	0.0146 (12)	−0.0061 (11)
C5	0.0374 (15)	0.0375 (13)	0.0252 (12)	−0.0056 (11)	0.0067 (11)	−0.0041 (10)
C6	0.0421 (16)	0.0405 (13)	0.0298 (13)	−0.0031 (11)	0.0090 (12)	−0.0046 (10)
C7	0.0427 (16)	0.0475 (14)	0.0282 (13)	−0.0042 (12)	0.0134 (12)	−0.0102 (11)
C8	0.0345 (15)	0.0411 (13)	0.0252 (13)	−0.0011 (11)	0.0074 (11)	−0.0064 (10)
C9	0.0385 (16)	0.0407 (13)	0.0255 (13)	−0.0017 (12)	0.0085 (12)	0.0040 (10)
C10	0.0326 (15)	0.0410 (13)	0.0281 (13)	0.0004 (11)	0.0068 (11)	0.0021 (10)
C11	0.067 (2)	0.0444 (15)	0.0515 (17)	0.0111 (13)	0.0313 (16)	0.0150 (12)
C12	0.071 (2)	0.0421 (14)	0.0606 (19)	0.0167 (14)	0.0354 (17)	0.0115 (13)
C13	0.0366 (15)	0.0410 (13)	0.0342 (14)	−0.0008 (11)	0.0119 (12)	0.0010 (11)
C14	0.0444 (17)	0.0446 (14)	0.0416 (15)	0.0044 (12)	0.0180 (13)	0.0120 (12)
C15	0.0427 (16)	0.0417 (13)	0.0456 (15)	0.0108 (12)	0.0156 (13)	0.0097 (12)
C16	0.0382 (16)	0.0424 (13)	0.0411 (14)	0.0012 (12)	0.0166 (13)	−0.0005 (11)
C17	0.0458 (19)	0.0787 (19)	0.0555 (18)	0.0067 (15)	0.0181 (15)	−0.0091 (15)
C18	0.096 (3)	0.0512 (17)	0.085 (2)	−0.0044 (16)	0.066 (2)	0.0018 (15)
C19	0.0552 (19)	0.0661 (18)	0.0408 (16)	0.0017 (14)	0.0158 (14)	−0.0035 (13)

Geometric parameters (Å, º) top

O1—C1	1.420 (3)	C10—C15	1.379 (3)
O1—H1	0.8400	C11—C12	1.386 (3)
O2—C9	1.359 (2)	C11—H11	0.9500
O2—C8	1.368 (2)	C12—C13	1.386 (3)
N1—C8	1.288 (3)	C12—H12	0.9500
N1—N2	1.405 (2)	C13—C14	1.377 (3)
N2—C9	1.289 (3)	C13—C16	1.536 (3)
C1—C2	1.516 (3)	C14—C15	1.382 (3)
C1—H1A	0.9900	C14—H14	0.9500
C1—H1B	0.9900	C15—H15	0.9500
C2—C7	1.391 (3)	C16—C17	1.525 (3)
C2—C3	1.391 (3)	C16—C19	1.527 (3)
C3—C4	1.383 (3)	C16—C18	1.528 (3)
C3—H3	0.9500	C17—H17A	0.9800
C4—C5	1.388 (3)	C17—H17B	0.9800
C4—H4	0.9500	C17—H17C	0.9800
C5—C6	1.394 (3)	C18—H18A	0.9800
C5—C8	1.457 (3)	C18—H18B	0.9800
C6—C7	1.382 (3)	C18—H18C	0.9800
C6—H6	0.9500	C19—H19A	0.9800
C7—H7	0.9500	C19—H19B	0.9800
C9—C10	1.463 (3)	C19—H19C	0.9800
C10—C11	1.379 (3)

C1—O1—H1	109.5	C10—C11—H11	119.9
C9—O2—C8	102.87 (16)	C12—C11—H11	119.9
C8—N1—N2	105.96 (17)	C11—C12—C13	122.1 (2)
C9—N2—N1	106.82 (17)	C11—C12—H12	119.0
O1—C1—C2	113.0 (2)	C13—C12—H12	119.0
O1—C1—H1A	109.0	C14—C13—C12	116.6 (2)
C2—C1—H1A	109.0	C14—C13—C16	122.48 (19)
O1—C1—H1B	109.0	C12—C13—C16	120.9 (2)
C2—C1—H1B	109.0	C13—C14—C15	122.2 (2)
H1A—C1—H1B	107.8	C13—C14—H14	118.9
C7—C2—C3	118.78 (19)	C15—C14—H14	118.9
C7—C2—C1	120.89 (19)	C10—C15—C14	120.4 (2)
C3—C2—C1	120.3 (2)	C10—C15—H15	119.8
C4—C3—C2	120.4 (2)	C14—C15—H15	119.8
C4—C3—H3	119.8	C17—C16—C19	108.9 (2)
C2—C3—H3	119.8	C17—C16—C18	108.8 (2)
C3—C4—C5	120.6 (2)	C19—C16—C18	108.7 (2)
C3—C4—H4	119.7	C17—C16—C13	110.55 (19)
C5—C4—H4	119.7	C19—C16—C13	107.72 (18)
C4—C5—C6	119.35 (19)	C18—C16—C13	111.99 (18)
C4—C5—C8	120.90 (19)	C16—C17—H17A	109.5
C6—C5—C8	119.7 (2)	C16—C17—H17B	109.5
C7—C6—C5	119.8 (2)	H17A—C17—H17B	109.5
C7—C6—H6	120.1	C16—C17—H17C	109.5
C5—C6—H6	120.1	H17A—C17—H17C	109.5
C6—C7—C2	121.1 (2)	H17B—C17—H17C	109.5
C6—C7—H7	119.4	C16—C18—H18A	109.5
C2—C7—H7	119.4	C16—C18—H18B	109.5
N1—C8—O2	112.30 (18)	H18A—C18—H18B	109.5
N1—C8—C5	128.60 (19)	C16—C18—H18C	109.5
O2—C8—C5	119.09 (19)	H18A—C18—H18C	109.5
N2—C9—O2	112.03 (17)	H18B—C18—H18C	109.5
N2—C9—C10	128.56 (19)	C16—C19—H19A	109.5
O2—C9—C10	119.41 (19)	C16—C19—H19B	109.5
C11—C10—C15	118.5 (2)	H19A—C19—H19B	109.5
C11—C10—C9	121.64 (19)	C16—C19—H19C	109.5
C15—C10—C9	119.8 (2)	H19A—C19—H19C	109.5
C10—C11—C12	120.2 (2)	H19B—C19—H19C	109.5

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N2ⁱ	0.84	2.07	2.906 (3)	179

Symmetry code: (i) x, −y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formula	C₁₉H₂₀N₂O₂
M_r	308.37
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	185
a, b, c (Å)	16.3958 (18), 6.0654 (7), 16.7206 (19)
β (°)	102.289 (2)
V (Å³)	1624.7 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.32 × 0.14 × 0.09

Data collection
Diffractometer	Bruker SMART APEX CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.974, 0.993
No. of measured, independent and observed [I > 2σ(I)] reflections	8995, 2886, 1805
R_int	0.051
(sin θ/λ)_max (Å⁻¹)	0.597

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.049, 0.122, 0.98
No. of reflections	2886
No. of parameters	212
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.16, −0.14

Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N2ⁱ	0.84	2.07	2.906 (3)	179

Symmetry code: (i) x, −y+1/2, z+1/2.

Acknowledgements

This work was supported by the Natural Science Foundation of Gansu Province (096RJZA086) and the project of students' science and technology innovation funds (DXS2010–041) of Lanzhou Jiaotong University.

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