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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 64| Part 8| August 2008| Page o1399
doi:10.1107/S1600536808019387

4-(2-Benzoyl­ethyl)benzoic acid

Roger A. Lalancettea* and Hugh W. Thompsona

aCarl A. Olson Memorial Laboratories, Department of Chemistry, Rutgers University, Newark, NJ 07102, USA
*Correspondence e-mail: rogerlal@andromeda.rutgers.edu

(Received 17 June 2008; accepted 25 June 2008; online 5 July 2008)

The title compound, C16H14O3, adopts a conformation in which each functional group is almost coplanar with its adjacent ring, while the two aromatic rings are twisted with respect to one another with a dihedral angle of 78.51 (3)°. The compound dimerizes by standard centrosymmetric hydrogen-bonded carboxyl pairing [O⋯O = 2.6218 (11) Å and O—H⋯O = 176 (2)°]. The packing includes two inter­molecular C—H⋯O close contacts with the ketone group.

Related literature

For related literature, see: Borthwick (1980[Borthwick, P. W. (1980). Acta Cryst. B36, 628-632.]); Steiner (1997[Steiner, T. (1997). Chem. Commun. pp. 727-734.]).

[Scheme 1]

Experimental

Crystal data

  • C16H14O3

  • Mr = 254.27

  • Monoclinic, P 21 /c

  • a = 7.3066 (1) Å

  • b = 8.7363 (1) Å

  • c = 19.6707 (3) Å

  • β = 90.296 (1)°

  • V = 1255.62 (3) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 0.75 mm−1

  • T = 100 (2) K

  • 0.27 × 0.21 × 0.15 mm
Data collection

  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2001[Sheldrick, G. M. (2001). SADABS. University of Göttingen, Germany.]) Tmin = 0.871, Tmax = 0.926

  • 8836 measured reflections

  • 2250 independent reflections

  • 2122 reflections with I > 2σ(I)

  • Rint = 0.024
Refinement

  • R[F2 > 2σ(F2)] = 0.032

  • wR(F2) = 0.085

  • S = 1.06

  • 2250 reflections

  • 177 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.24 e Å−3

  • Δρmin = −0.15 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O3—H3A⋯O2i 0.97 (2) 1.66 (2) 2.6218 (11) 176 (2)
C5—H5⋯O1ii 0.95 2.59 3.3786 (14) 140
C8—H8A⋯O1iii 0.99 2.54 3.4864 (14) 160
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) x+1, y, z; (iii) [-x-1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2006[Bruker (2006). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2005[Bruker (2005). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808019387/fl2203sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808019387/fl2203Isup2.hkl

checkCIF report


Comment top

Our X-ray study of ketocarboxylic acids seeks to uncover the structural features governing the choice among the five known keto–acid hydrogen-bonding modes. One major determinant is the availability of centrosymmetry, such that carboxyl dimerization, overall the commonest type of aggregation, is rare among single enantiomers. A second important influence is molecular flexibility, as reflected by the number of fully rotatable bonds in the molecule, with dimerization becoming less common as structural or conformational rigidity increases. In this context, the title molecule (I) is relatively flexible, containing four fully rotatable bonds in addition to the carboxyl.

Fig. 1 shows the asymmetric unit for (I) with its numbering. A principal feature is the near coplanarity of the two carbonyl-bearing functional groups with their respective benzene rings, permitting strong conjugation. The phenone's dihedral angle is 7.83 (8)° (C8—C9—C10—O1 versus C10—C11—C12—C13—C14—C15) and that for the carboxylic acid is 19.92 (6)° (C1—C16—O2—O3 versus C1—C2—C3—C4—C5—C6). The connecting alkyl chain, however, is not maximally staggered, the C4—C7—C8—C9 torsion being -160.20 (10)° rather than 180°. The two separate aromatic rings lie at a mutual dihedral angle of 78.51 (3)°.

Carboxyl dimers often display complete or partial averaging of C—O bond lengths and C—C—O angles due to disorder; however, no significant averaging is observed in (I), where these lengths and angles are similar to those in other highly ordered carboxyl situations (Borthwick, 1980).

Fig. 2 shows the packing arrangement for (I), typical for acids that are either racemic or, as with (I), achiral but capable of forming conformational racemates. Centrosymmetric dimers with two different orientations are centered at 1/2,1/2,1/2 and 1/2,0,0 in the chosen cell. The eight-membered carboxyl dimer of one orientational type lies close to the phenone aromatic ring in a dimer of the second type and nearly parallel to it [dihedral angle = 6.38 (7)°]. The normal distance from the centroid of this ring to the carboxyl-dimer plane = 3.472 Å and the intermolecular acid-to-ketone O═C···C═O distance = 3.3508 (15) Å.

Two intermolecular C—H···O═C close contacts were found in the packing, linking the ketone (O1) to H8A and to H5 in separate neighboring molecules (Table 1). These contacts lie within the 2.6 Å range we routinely survey for non-bonded dipolar packing interactions (Steiner, 1997).

Related literature top

For related literature, see: Borthwick (1980); Steiner (1997).

Experimental top

Methyl 4-(3-oxo-3-phenyl-1-propenyl)benzoate, purchased from Acros Organics/Fisher Scientific, Springfield, NJ, USA, was hydrogenated in ethyl acetate at atmospheric pressure and room temperature over a 5% Pd/C catalyst. The resulting reduced methyl ester, m.p. ca 365 K, was saponified by refluxing with aqueous KOH to yield (I). Crystals of X-ray quality were obtained from Et2O, m.p. 431 K. Typically for carboxyl-paired keto acids, the solid-state (KBr) and the solution infrared spectra of (I) display only slight differences in the C═O region. The former features intense absorption at 1682 cm-1 for both C═O functions; in CHCl3 solution this combined peak is seen at 1688 cm-1.

Refinement top

All H atoms for (I) were found in electron density difference maps. The positional parameters and the isotropic thermal parameter of the O—H were allowed to refine fully. The methylene and the phenyl Hs were placed in geometrically idealized positions and constrained to ride on their parent C atoms with C—H distances of 0.99 Å for the methylene Hs and 0.95 Å for the phenyl Hs, and Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: APEX2 (Bruker, 2006); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of (I), with its numbering. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. A partial packing diagram for (I), illustrating the dihedral relationships among the aromatic rings of the packed centrosymmetric dimers located at 1/2,1/2,1/2 and 1/2,0,0 in the unit cell. Displacement ellipsoids are drawn at the 30% probability level.
4-(2-Benzoylethyl)benzoic acid top
Crystal data top
C16H14O3F(000) = 536
Mr = 254.27Dx = 1.345 Mg m−3
Monoclinic, P21/cMelting point: 431 K
Hall symbol: -P 2ybcCu Kα radiation, λ = 1.54178 Å
a = 7.3066 (1) ÅCell parameters from 6862 reflections
b = 8.7363 (1) Åθ = 5.1–69.6°
c = 19.6707 (3) ŵ = 0.75 mm−1
β = 90.296 (1)°T = 100 K
V = 1255.62 (3) Å3Block, colourless
Z = 40.27 × 0.21 × 0.15 mm
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer		2250 independent reflections
Radiation source: fine-focus sealed tube2122 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
ϕ and ω scansθmax = 69.9°, θmin = 5.5°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2001)		h = −8→7
Tmin = 0.871, Tmax = 0.927k = −10→10
8836 measured reflectionsl = −20→23
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.032H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.085 w = 1/[σ2(Fo2) + (0.0362P)2 + 0.5203P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max < 0.001
2250 reflectionsΔρmax = 0.24 e Å−3
177 parametersΔρmin = −0.15 e Å−3
0 restraintsExtinction correction: SHELXTL (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0010 (3)
Crystal data top
C16H14O3V = 1255.62 (3) Å3
Mr = 254.27Z = 4
Monoclinic, P21/cCu Kα radiation
a = 7.3066 (1) ŵ = 0.75 mm−1
b = 8.7363 (1) ÅT = 100 K
c = 19.6707 (3) Å0.27 × 0.21 × 0.15 mm
β = 90.296 (1)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer		2250 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2001)		2122 reflections with I > 2σ(I)
Tmin = 0.871, Tmax = 0.927Rint = 0.024
8836 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0320 restraints
wR(F2) = 0.085H atoms treated by a mixture of independent and constrained refinement
S = 1.06Δρmax = 0.24 e Å−3
2250 reflectionsΔρmin = −0.15 e Å−3
177 parameters
Special details top

Experimental. 'crystal mounted on cryoloop using Paratone-N'

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
xyzUiso*/Ueq
O1−0.51626 (11)0.00590 (9)0.20479 (4)0.0244 (2)
C10.20287 (16)0.31711 (13)0.39461 (6)0.0183 (2)
O20.49306 (11)0.35014 (10)0.44785 (4)0.0225 (2)
C20.01509 (16)0.34231 (13)0.40114 (6)0.0201 (3)
H2−0.02890.41210.43430.024*
C3−0.10693 (16)0.26552 (14)0.35930 (6)0.0209 (3)
H3−0.23450.28280.36430.025*
O30.27242 (12)0.52180 (10)0.46838 (4)0.0237 (2)
H3A0.363 (3)0.565 (3)0.4988 (12)0.078 (7)*
C4−0.04556 (16)0.16284 (13)0.30981 (6)0.0192 (3)
C50.14214 (16)0.13923 (13)0.30362 (6)0.0198 (3)
H50.18630.07020.27020.024*
C60.26570 (16)0.21514 (13)0.34560 (6)0.0197 (3)
H60.39330.19750.34090.024*
C7−0.18159 (16)0.08144 (13)0.26458 (6)0.0215 (3)
H7A−0.27320.02880.29320.026*
H7B−0.11700.00280.23760.026*
C8−0.27993 (16)0.19232 (14)0.21631 (6)0.0214 (3)
H8A−0.30530.28870.24100.026*
H8B−0.19730.21710.17810.026*
C9−0.45757 (16)0.13083 (13)0.18776 (6)0.0199 (3)
C10−0.56580 (16)0.23037 (14)0.14032 (6)0.0206 (3)
C11−0.74205 (17)0.18477 (15)0.12200 (6)0.0238 (3)
H11−0.78930.09070.13860.029*
C12−0.84914 (18)0.27529 (16)0.07976 (6)0.0279 (3)
H12−0.96890.24320.06730.033*
C13−0.78050 (18)0.41321 (16)0.05569 (6)0.0290 (3)
H13−0.85380.47560.02680.035*
C14−0.60602 (18)0.46002 (15)0.07354 (6)0.0272 (3)
H14−0.55980.55460.05710.033*
C15−0.49839 (17)0.36867 (14)0.11544 (6)0.0232 (3)
H15−0.37810.40060.12720.028*
C160.33506 (15)0.39769 (13)0.43939 (5)0.0184 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0238 (5)0.0218 (4)0.0277 (5)−0.0025 (3)−0.0032 (3)0.0005 (3)
C10.0207 (6)0.0181 (5)0.0162 (5)0.0004 (4)−0.0022 (4)0.0026 (4)
O20.0187 (5)0.0262 (5)0.0224 (4)0.0019 (3)−0.0038 (3)−0.0036 (3)
C20.0225 (6)0.0205 (6)0.0172 (6)0.0024 (4)0.0000 (4)−0.0012 (4)
C30.0176 (6)0.0234 (6)0.0216 (6)0.0010 (4)−0.0012 (4)−0.0001 (5)
O30.0227 (5)0.0231 (4)0.0254 (4)0.0016 (3)−0.0040 (3)−0.0072 (3)
C40.0223 (6)0.0184 (6)0.0169 (6)−0.0008 (4)−0.0031 (4)0.0019 (4)
C50.0238 (6)0.0189 (6)0.0168 (5)0.0024 (4)−0.0006 (4)−0.0007 (4)
C60.0185 (6)0.0213 (6)0.0192 (6)0.0019 (4)−0.0012 (4)0.0013 (4)
C70.0224 (6)0.0206 (6)0.0214 (6)0.0000 (5)−0.0034 (4)−0.0025 (5)
C80.0219 (6)0.0223 (6)0.0200 (6)−0.0021 (5)−0.0031 (4)−0.0005 (5)
C90.0207 (6)0.0213 (6)0.0177 (6)0.0004 (4)0.0011 (4)−0.0045 (4)
C100.0223 (6)0.0237 (6)0.0157 (5)0.0006 (5)−0.0007 (4)−0.0045 (5)
C110.0249 (7)0.0267 (6)0.0199 (6)−0.0022 (5)−0.0017 (5)−0.0023 (5)
C120.0243 (7)0.0366 (7)0.0228 (6)0.0008 (5)−0.0054 (5)−0.0038 (5)
C130.0334 (7)0.0332 (7)0.0205 (6)0.0073 (6)−0.0068 (5)−0.0006 (5)
C140.0359 (7)0.0248 (6)0.0210 (6)−0.0002 (5)−0.0018 (5)0.0009 (5)
C150.0252 (7)0.0249 (6)0.0196 (6)−0.0014 (5)−0.0023 (5)−0.0029 (5)
C160.0200 (6)0.0198 (6)0.0153 (5)0.0001 (4)0.0000 (4)0.0021 (4)
Geometric parameters (Å, º) top
O1—C91.2202 (14)C7—H7A0.9900
C1—C61.3923 (16)C7—H7B0.9900
C1—C21.3961 (17)C8—C91.5104 (16)
C1—C161.4818 (15)C8—H8A0.9900
O2—C161.2373 (14)C8—H8B0.9900
C2—C31.3837 (16)C9—C101.4983 (16)
C2—H20.9500C10—C111.3936 (17)
C3—C41.3992 (16)C10—C151.3944 (17)
C3—H30.9500C11—C121.3861 (18)
O3—C161.3088 (14)C11—H110.9500
O3—H3A0.97 (2)C12—C131.389 (2)
C4—C51.3928 (17)C12—H120.9500
C4—C71.5087 (15)C13—C141.3825 (19)
C5—C61.3889 (16)C13—H130.9500
C5—H50.9500C14—C151.3885 (17)
C6—H60.9500C14—H140.9500
C7—C81.5326 (16)C15—H150.9500
C6—C1—C2119.49 (11)C9—C8—H8B108.8
C6—C1—C16119.96 (10)C7—C8—H8B108.8
C2—C1—C16120.55 (10)H8A—C8—H8B107.7
C3—C2—C1119.95 (10)O1—C9—C10120.34 (11)
C3—C2—H2120.0O1—C9—C8121.24 (11)
C1—C2—H2120.0C10—C9—C8118.36 (10)
C2—C3—C4121.12 (11)C11—C10—C15118.98 (11)
C2—C3—H3119.4C11—C10—C9118.63 (11)
C4—C3—H3119.4C15—C10—C9122.36 (11)
C16—O3—H3A110.8 (13)C12—C11—C10120.66 (12)
C5—C4—C3118.36 (10)C12—C11—H11119.7
C5—C4—C7121.64 (10)C10—C11—H11119.7
C3—C4—C7120.00 (10)C11—C12—C13119.70 (12)
C6—C5—C4120.97 (11)C11—C12—H12120.1
C6—C5—H5119.5C13—C12—H12120.1
C4—C5—H5119.5C14—C13—C12120.27 (12)
C5—C6—C1120.11 (11)C14—C13—H13119.9
C5—C6—H6119.9C12—C13—H13119.9
C1—C6—H6119.9C13—C14—C15119.96 (12)
C4—C7—C8111.89 (9)C13—C14—H14120.0
C4—C7—H7A109.2C15—C14—H14120.0
C8—C7—H7A109.2C14—C15—C10120.42 (12)
C4—C7—H7B109.2C14—C15—H15119.8
C8—C7—H7B109.2C10—C15—H15119.8
H7A—C7—H7B107.9O2—C16—O3123.21 (10)
C9—C8—C7113.88 (10)O2—C16—C1121.69 (10)
C9—C8—H8A108.8O3—C16—C1115.10 (10)
C7—C8—H8A108.8
C6—C1—C2—C30.34 (17)C8—C9—C10—C11−170.32 (10)
C16—C1—C2—C3−179.56 (10)O1—C9—C10—C15−175.08 (11)
C1—C2—C3—C4−0.39 (17)C8—C9—C10—C157.87 (16)
C2—C3—C4—C50.11 (17)C15—C10—C11—C12−0.05 (18)
C2—C3—C4—C7−179.60 (10)C9—C10—C11—C12178.20 (10)
C3—C4—C5—C60.22 (17)C10—C11—C12—C13−0.32 (18)
C7—C4—C5—C6179.93 (10)C11—C12—C13—C140.20 (19)
C4—C5—C6—C1−0.27 (17)C12—C13—C14—C150.29 (19)
C2—C1—C6—C5−0.01 (17)C13—C14—C15—C10−0.67 (18)
C16—C1—C6—C5179.89 (10)C11—C10—C15—C140.55 (17)
C5—C4—C7—C8−112.51 (12)C9—C10—C15—C14−177.64 (10)
C3—C4—C7—C867.19 (14)C6—C1—C16—O2−19.53 (16)
C4—C7—C8—C9−160.20 (10)C2—C1—C16—O2160.37 (11)
C7—C8—C9—O12.55 (16)C6—C1—C16—O3160.00 (10)
C7—C8—C9—C10179.57 (9)C2—C1—C16—O3−20.10 (15)
O1—C9—C10—C116.72 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···O2i0.97 (2)1.66 (2)2.6218 (11)176 (2)
C5—H5···O1ii0.952.593.3786 (14)140
C8—H8A···O1iii0.992.543.4864 (14)160
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x+1, y, z; (iii) −x−1, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formulaC16H14O3
Mr254.27
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)7.3066 (1), 8.7363 (1), 19.6707 (3)
β (°) 90.296 (1)
V (Å3)1255.62 (3)
Z4
Radiation typeCu Kα
µ (mm−1)0.75
Crystal size (mm)0.27 × 0.21 × 0.15
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2001)
Tmin, Tmax0.871, 0.927
No. of measured, independent and
observed [I > 2σ(I)] reflections		8836, 2250, 2122
Rint0.024
(sin θ/λ)max (Å−1)0.609
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.032, 0.085, 1.06
No. of reflections2250
No. of parameters177
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.24, −0.15

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···O2i0.97 (2)1.66 (2)2.6218 (11)176 (2)
C5—H5···O1ii0.952.593.3786 (14)140
C8—H8A···O1iii0.992.543.4864 (14)160
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x+1, y, z; (iii) −x−1, y+1/2, −z+1/2.
 

Acknowledgements

HWT is grateful to Professor Gree Loober Spoog for helpful consultations. The authors acknowledge support by NSF–CRIF grant No. 0443538.

References

First citationBorthwick, P. W. (1980). Acta Cryst. B36, 628–632.  CrossRef CAS IUCr Journals Web of Science Google Scholar
 First citationBruker (2005). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationBruker (2006). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationSheldrick, G. M. (2001). SADABS. University of Göttingen, Germany.  Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationSteiner, T. (1997). Chem. Commun. pp. 727–734.  CrossRef Web of Science Google Scholar

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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 64| Part 8| August 2008| Page o1399
doi:10.1107/S1600536808019387
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