3,4-Diphenyl-2,5-bis­(trimethyl­silyl)cyclo­penta­dienone

Saito, M.; Ito, T.

doi:10.1107/S1600536808032923

organic compounds

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ISSN: 2056-9890

Volume 64| Part 11| November 2008| Page o2121

doi:10.1107/S1600536808032923

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3,4-Diphenyl-2,5-bis(trimethylsilyl)cyclopentadienone

Masaichi Saito ^a ^* and Toru Ito ^a

^aDepartment of Chemistry, Graduate School of Science and Engineering, Saitama University, Shimo-okubo, Saitama City, Saitama 338-8570, Japan
^*Correspondence e-mail: masaichi@chem.saitama-u.ac.jp

(Received 13 September 2008; accepted 11 October 2008; online 18 October 2008)

In the title compound, C₂₃H₂₈OSi₂, the five-membered ring is essentially planar and the phenyl rings are oriented with respect to the mean plane of this ring by 56.01 (3) and 56.68 (4)°.

Related literature

For a previous report of the synthesis of the title compound, see: Rajesh & Periasamy (1999 ). For related structures, see: Barnes et al. (1991 ); Ruffani et al. (2006 ).

Experimental

Crystal data

C₂₃H₂₈OSi₂
M_r = 376.63
Orthorhombic, P 2₁ 2₁ 2₁
a = 9.8418 (6) Å
b = 11.8041 (7) Å
c = 19.0181 (12) Å
V = 2209.4 (2) Å³
Z = 4
Mo Kα radiation
μ = 0.17 mm⁻¹
T = 103 (3) K
0.50 × 0.40 × 0.40 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.922, T_max = 0.935
16200 measured reflections
5286 independent reflections
5181 reflections with I > 2σ(I)
R_int = 0.021

Refinement

R[F² > 2σ(F²)] = 0.028
wR(F²) = 0.075
S = 1.07
5286 reflections
241 parameters
H-atom parameters constrained
Δρ_max = 0.28 e Å⁻³
Δρ_min = −0.20 e Å⁻³
Absolute structure: Flack (1983 ), with 2292 Friedel pairs
Flack parameter: 0.01 (6)

Data collection: SMART (Bruker, 2000 ); cell refinement: SAINT (Bruker, 2000); 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/S1600536808032923/pv2107sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808032923/pv2107Isup2.hkl

checkCIF report

Comment top

Although the synthesis of the title compound, (I), was already reported (Rajesh & Periasamy, 1999), the reported NMR data were incorrect. Thus, we report herein the molecular structure of the title compound and revise its NMR data. The five-membered ring and four bonds derived from the each of carbon atoms in the five-membered ring are situated in a planar geometry, as was observed in the tetraphenylcyclopentadienone (Barnes et al., 1991). Bond alternation of the C—C bonds in the five-membered ring of (I) is found, as was observed in other cyclopentadienones (Barnes et al., 1991; Ruffani et al., 2006). The C1—O1 distance (1.2139 (15) Å) in (I), is quite similar to that found in the tetraphenyl derivative (Barnes et al., 1991).

Related literature top

For a previous report of the synthesis of the title compound, see: Rajesh & Periasamy (1999). For related structures, see: Barnes et al. (1991); Ruffani et al. (2006). [Please check added text]

Experimental top

To lithium (32 mg, 4.61 mmol) was added a diethyl ether (2.5 ml) solution of phenyl(trimethylsilyl)acetylene (408 mg, 2.34 mmol) and the resulting mixture was stirred at room temperature for 4 h. To an ether solution of 1,4-dilithio-1,3-butadiene thus obtained was added diethyl ether (8 ml) and unreacted lithium was removed by filtration. Carbon dioxide was bubbled into the filtrate at room temperature for 1 min. After treatment of the resulting mixture with hydrochloric acid (3 N), the organic layer was extracted with diethyl ether and dried over anhydrous magnesium sulfate. After removal of volatile substances, the residue was subjected to column chromatography (SiO₂, hexane:ethyl acetate = 30:1) to afford the title compound, 3,4-diphenyl-2,5-bis(trimethylsilyl)cyclopentadienone (I) (22 mg, 5%). Suitable crystals for X-ray crystallographic analysis were obtained by slow evaporation of a hexane solution of (I).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); 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. A view of the molecule of (I) showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 40% probability level.

3,4-Diphenyl-2,5-bis(trimethylsilyl)cyclopentadienone top

Crystal data top

C₂₃H₂₈OSi₂	F(000) = 808
M_r = 376.63	D_x = 1.132 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 5798 reflections
a = 9.8418 (6) Å	θ = 2.7–27.9°
b = 11.8041 (7) Å	µ = 0.17 mm⁻¹
c = 19.0181 (12) Å	T = 103 K
V = 2209.4 (2) Å³	Cube, orange
Z = 4	0.50 × 0.40 × 0.40 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	5286 independent reflections
Radiation source: fine-focus sealed tube	5181 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.021
ϕ and ω scans	θ_max = 27.9°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −12→11
T_min = 0.922, T_max = 0.935	k = −15→15
16200 measured reflections	l = −21→25

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.028	H-atom parameters constrained
wR(F²) = 0.075	w = 1/[σ²(F_o²) + (0.0473P)² + 0.2508P] where P = (F_o² + 2F_c²)/3
S = 1.07	(Δ/σ)_max = 0.001
5286 reflections	Δρ_max = 0.28 e Å⁻³
241 parameters	Δρ_min = −0.20 e Å⁻³
0 restraints	Absolute structure: Flack (1983), with 2292 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.01 (6)

Crystal data top

C₂₃H₂₈OSi₂	V = 2209.4 (2) Å³
M_r = 376.63	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 9.8418 (6) Å	µ = 0.17 mm⁻¹
b = 11.8041 (7) Å	T = 103 K
c = 19.0181 (12) Å	0.50 × 0.40 × 0.40 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	5286 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	5181 reflections with I > 2σ(I)
T_min = 0.922, T_max = 0.935	R_int = 0.021
16200 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.028	H-atom parameters constrained
wR(F²) = 0.075	Δρ_max = 0.28 e Å⁻³
S = 1.07	Δρ_min = −0.20 e Å⁻³
5286 reflections	Absolute structure: Flack (1983), with 2292 Friedel pairs
241 parameters	Absolute structure parameter: 0.01 (6)
0 restraints

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. The Flack parameter was not changed after least-square refinement without merging the reflections. When the refinement was carried out using the opposite absolute structure, the Flack parameter was 0.99 (7).

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

	x	y	z	U_iso*/U_eq
Si1	0.18748 (3)	1.12044 (3)	0.976841 (17)	0.01882 (8)
Si2	0.42760 (3)	0.77489 (3)	0.787011 (18)	0.02008 (8)
O1	0.42093 (9)	1.01676 (8)	0.87657 (5)	0.0272 (2)
C2	0.18860 (12)	0.99471 (10)	0.91621 (6)	0.0180 (2)
C15	0.08537 (12)	0.72378 (10)	0.82868 (6)	0.0190 (2)
C7	0.03840 (14)	1.11986 (13)	1.03721 (7)	0.0289 (3)
H7A	0.0361	1.0497	1.0627	0.043*
H7B	−0.0436	1.1278	1.0103	0.043*
H7C	0.0459	1.1818	1.0697	0.043*
C3	0.09673 (12)	0.91490 (9)	0.89917 (6)	0.0176 (2)
C6	0.18912 (15)	1.25143 (10)	0.92156 (7)	0.0267 (3)
H6A	0.1116	1.2513	0.8909	0.040*
H6B	0.2708	1.2533	0.8940	0.040*
H6C	0.1858	1.3170	0.9514	0.040*
C16	−0.03609 (13)	0.73727 (11)	0.79091 (7)	0.0229 (2)
H16	−0.0694	0.8096	0.7819	0.028*
C12	−0.31728 (13)	0.90660 (12)	0.96478 (7)	0.0263 (3)
H12	−0.4070	0.9059	0.9802	0.032*
C9	−0.04729 (11)	0.91027 (10)	0.92063 (6)	0.0181 (2)
C10	−0.13363 (12)	1.00076 (11)	0.90568 (6)	0.0209 (2)
H10	−0.1009	1.0628	0.8807	0.025*
C14	−0.09904 (13)	0.81670 (11)	0.95650 (6)	0.0227 (2)
H14	−0.0432	0.7548	0.9654	0.027*
C4	0.16243 (12)	0.82381 (10)	0.85340 (6)	0.0181 (2)
C18	−0.06037 (15)	0.53448 (11)	0.78188 (7)	0.0290 (3)
H18	−0.1087	0.4716	0.7662	0.035*
C8	0.34391 (14)	1.11229 (13)	1.03210 (7)	0.0318 (3)
H8A	0.3455	1.1748	1.0644	0.048*
H8B	0.4227	1.1154	1.0024	0.048*
H8C	0.3440	1.0424	1.0580	0.048*
C1	0.31734 (12)	0.96101 (10)	0.87823 (6)	0.0191 (2)
C20	0.13106 (14)	0.61403 (11)	0.84330 (7)	0.0228 (2)
H20	0.2109	0.6037	0.8686	0.027*
C22	0.55418 (15)	0.87927 (12)	0.75313 (8)	0.0333 (3)
H22A	0.6181	0.8412	0.7232	0.050*
H22B	0.6015	0.9131	0.7919	0.050*
H22C	0.5081	0.9371	0.7269	0.050*
C13	−0.23314 (13)	0.81532 (12)	0.97897 (7)	0.0271 (3)
H13	−0.2665	0.7532	1.0035	0.033*
C11	−0.26813 (13)	0.99900 (12)	0.92774 (7)	0.0241 (3)
H11	−0.3251	1.0597	0.9177	0.029*
C5	0.29427 (12)	0.84939 (10)	0.84058 (6)	0.0185 (2)
C23	0.34694 (14)	0.70279 (12)	0.71046 (7)	0.0292 (3)
H23A	0.4161	0.6693	0.6816	0.044*
H23B	0.2967	0.7571	0.6834	0.044*
H23C	0.2865	0.6448	0.7270	0.044*
C19	0.05826 (15)	0.52031 (11)	0.82031 (7)	0.0284 (3)
H19	0.0891	0.4478	0.8307	0.034*
C17	−0.10663 (13)	0.64309 (12)	0.76695 (7)	0.0275 (3)
H17	−0.1855	0.6527	0.7407	0.033*
C21	0.51771 (14)	0.67089 (12)	0.84432 (8)	0.0287 (3)
H21A	0.4534	0.6176	0.8630	0.043*
H21B	0.5612	0.7102	0.8823	0.043*
H21C	0.5849	0.6313	0.8172	0.043*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Si1	0.01810 (15)	0.01801 (15)	0.02036 (15)	−0.00020 (12)	−0.00082 (12)	−0.00287 (12)
Si2	0.02101 (15)	0.01866 (15)	0.02057 (15)	0.00210 (12)	0.00300 (12)	−0.00136 (12)
O1	0.0186 (4)	0.0265 (4)	0.0366 (5)	−0.0041 (4)	0.0035 (4)	−0.0071 (4)
C2	0.0175 (5)	0.0178 (5)	0.0188 (5)	0.0023 (4)	−0.0003 (4)	−0.0005 (4)
C15	0.0209 (5)	0.0197 (5)	0.0164 (5)	−0.0020 (5)	0.0017 (4)	−0.0011 (4)
C7	0.0289 (6)	0.0320 (7)	0.0257 (6)	−0.0020 (6)	0.0058 (5)	−0.0061 (5)
C3	0.0185 (5)	0.0167 (5)	0.0175 (5)	0.0021 (4)	−0.0003 (4)	0.0020 (4)
C6	0.0322 (6)	0.0188 (6)	0.0291 (6)	−0.0009 (5)	0.0004 (5)	−0.0004 (4)
C16	0.0236 (6)	0.0232 (6)	0.0220 (5)	−0.0004 (5)	−0.0011 (5)	−0.0002 (5)
C12	0.0178 (5)	0.0358 (7)	0.0253 (6)	−0.0019 (5)	0.0025 (5)	0.0021 (5)
C9	0.0171 (5)	0.0196 (5)	0.0175 (5)	−0.0005 (4)	−0.0025 (4)	−0.0023 (4)
C10	0.0200 (5)	0.0204 (5)	0.0224 (5)	−0.0003 (5)	−0.0006 (4)	0.0025 (4)
C14	0.0232 (6)	0.0230 (6)	0.0219 (6)	0.0017 (5)	0.0000 (5)	0.0042 (4)
C4	0.0216 (6)	0.0166 (5)	0.0162 (5)	0.0022 (4)	−0.0010 (4)	0.0015 (4)
C18	0.0361 (7)	0.0251 (6)	0.0256 (6)	−0.0110 (5)	0.0011 (6)	−0.0062 (5)
C8	0.0267 (6)	0.0374 (7)	0.0315 (7)	0.0009 (6)	−0.0092 (5)	−0.0060 (6)
C1	0.0180 (5)	0.0190 (5)	0.0202 (5)	0.0028 (4)	−0.0005 (4)	0.0008 (4)
C20	0.0265 (6)	0.0207 (6)	0.0211 (5)	−0.0003 (5)	−0.0004 (5)	−0.0003 (5)
C22	0.0341 (7)	0.0291 (6)	0.0367 (7)	−0.0043 (6)	0.0147 (6)	−0.0016 (6)
C13	0.0251 (6)	0.0316 (7)	0.0246 (6)	−0.0039 (5)	0.0021 (5)	0.0075 (5)
C11	0.0194 (6)	0.0264 (6)	0.0264 (6)	0.0035 (5)	−0.0020 (5)	0.0007 (5)
C5	0.0205 (6)	0.0167 (5)	0.0183 (5)	0.0015 (4)	−0.0007 (4)	0.0002 (4)
C23	0.0331 (7)	0.0327 (7)	0.0217 (6)	−0.0001 (5)	0.0027 (5)	−0.0064 (5)
C19	0.0383 (7)	0.0183 (6)	0.0285 (6)	−0.0024 (5)	0.0024 (6)	−0.0005 (5)
C17	0.0251 (6)	0.0340 (7)	0.0234 (6)	−0.0052 (5)	−0.0028 (5)	−0.0023 (5)
C21	0.0269 (6)	0.0269 (6)	0.0323 (7)	0.0074 (5)	−0.0012 (5)	0.0004 (5)

Geometric parameters (Å, º) top

Si1—C7	1.8630 (13)	C9—C14	1.3946 (17)
Si1—C8	1.8666 (14)	C10—C11	1.3887 (17)
Si1—C6	1.8699 (13)	C10—H10	0.9300
Si1—C2	1.8795 (12)	C14—C13	1.3873 (19)
Si2—C23	1.8640 (14)	C14—H14	0.9300
Si2—C21	1.8659 (14)	C4—C5	1.3544 (17)
Si2—C22	1.8668 (14)	C18—C19	1.388 (2)
Si2—C5	1.8796 (12)	C18—C17	1.390 (2)
O1—C1	1.2139 (15)	C18—H18	0.9300
C2—C3	1.3454 (16)	C8—H8A	0.9600
C2—C1	1.5117 (16)	C8—H8B	0.9600
C15—C20	1.3993 (17)	C8—H8C	0.9600
C15—C16	1.4037 (17)	C1—C5	1.5166 (16)
C15—C4	1.4799 (16)	C20—C19	1.3886 (18)
C7—H7A	0.9600	C20—H20	0.9300
C7—H7B	0.9600	C22—H22A	0.9600
C7—H7C	0.9600	C22—H22B	0.9600
C3—C9	1.4760 (16)	C22—H22C	0.9600
C3—C4	1.5271 (16)	C13—H13	0.9300
C6—H6A	0.9600	C11—H11	0.9300
C6—H6B	0.9600	C23—H23A	0.9600
C6—H6C	0.9600	C23—H23B	0.9600
C16—C17	1.3876 (18)	C23—H23C	0.9600
C16—H16	0.9300	C19—H19	0.9300
C12—C11	1.3855 (19)	C17—H17	0.9300
C12—C13	1.3855 (19)	C21—H21A	0.9600
C12—H12	0.9300	C21—H21B	0.9600
C9—C10	1.3942 (16)	C21—H21C	0.9600

C7—Si1—C8	107.60 (6)	C15—C4—C3	121.72 (10)
C7—Si1—C6	110.88 (7)	C19—C18—C17	119.63 (12)
C8—Si1—C6	110.62 (7)	C19—C18—H18	120.2
C7—Si1—C2	112.32 (6)	C17—C18—H18	120.2
C8—Si1—C2	107.45 (6)	Si1—C8—H8A	109.5
C6—Si1—C2	107.94 (5)	Si1—C8—H8B	109.5
C23—Si2—C21	110.99 (6)	H8A—C8—H8B	109.5
C23—Si2—C22	108.42 (7)	Si1—C8—H8C	109.5
C21—Si2—C22	108.58 (7)	H8A—C8—H8C	109.5
C23—Si2—C5	109.86 (6)	H8B—C8—H8C	109.5
C21—Si2—C5	108.84 (6)	O1—C1—C2	125.01 (11)
C22—Si2—C5	110.13 (6)	O1—C1—C5	125.76 (11)
C3—C2—C1	105.30 (10)	C2—C1—C5	109.19 (10)
C3—C2—Si1	134.17 (9)	C19—C20—C15	120.61 (12)
C1—C2—Si1	120.39 (8)	C19—C20—H20	119.7
C20—C15—C16	118.71 (11)	C15—C20—H20	119.7
C20—C15—C4	120.72 (11)	Si2—C22—H22A	109.5
C16—C15—C4	120.56 (11)	Si2—C22—H22B	109.5
Si1—C7—H7A	109.5	H22A—C22—H22B	109.5
Si1—C7—H7B	109.5	Si2—C22—H22C	109.5
H7A—C7—H7B	109.5	H22A—C22—H22C	109.5
Si1—C7—H7C	109.5	H22B—C22—H22C	109.5
H7A—C7—H7C	109.5	C12—C13—C14	119.96 (12)
H7B—C7—H7C	109.5	C12—C13—H13	120.0
C2—C3—C9	127.20 (11)	C14—C13—H13	120.0
C2—C3—C4	110.23 (10)	C12—C11—C10	119.88 (12)
C9—C3—C4	122.56 (10)	C12—C11—H11	120.1
Si1—C6—H6A	109.5	C10—C11—H11	120.1
Si1—C6—H6B	109.5	C4—C5—C1	104.61 (10)
H6A—C6—H6B	109.5	C4—C5—Si2	131.46 (9)
Si1—C6—H6C	109.5	C1—C5—Si2	123.91 (9)
H6A—C6—H6C	109.5	Si2—C23—H23A	109.5
H6B—C6—H6C	109.5	Si2—C23—H23B	109.5
C17—C16—C15	120.21 (11)	H23A—C23—H23B	109.5
C17—C16—H16	119.9	Si2—C23—H23C	109.5
C15—C16—H16	119.9	H23A—C23—H23C	109.5
C11—C12—C13	120.17 (12)	H23B—C23—H23C	109.5
C11—C12—H12	119.9	C18—C19—C20	120.27 (12)
C13—C12—H12	119.9	C18—C19—H19	119.9
C10—C9—C14	118.95 (11)	C20—C19—H19	119.9
C10—C9—C3	120.03 (11)	C16—C17—C18	120.54 (12)
C14—C9—C3	121.02 (11)	C16—C17—H17	119.7
C11—C10—C9	120.52 (12)	C18—C17—H17	119.7
C11—C10—H10	119.7	Si2—C21—H21A	109.5
C9—C10—H10	119.7	Si2—C21—H21B	109.5
C13—C14—C9	120.49 (12)	H21A—C21—H21B	109.5
C13—C14—H14	119.8	Si2—C21—H21C	109.5
C9—C14—H14	119.8	H21A—C21—H21C	109.5
C5—C4—C15	127.71 (11)	H21B—C21—H21C	109.5
C5—C4—C3	110.56 (10)

Experimental details

Crystal data
Chemical formula	C₂₃H₂₈OSi₂
M_r	376.63
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	103
a, b, c (Å)	9.8418 (6), 11.8041 (7), 19.0181 (12)
V (Å³)	2209.4 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.17
Crystal size (mm)	0.50 × 0.40 × 0.40

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.922, 0.935
No. of measured, independent and observed [I > 2σ(I)] reflections	16200, 5286, 5181
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.659

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.028, 0.075, 1.07
No. of reflections	5286
No. of parameters	241
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.28, −0.20
Absolute structure	Flack (1983), with 2292 Friedel pairs
Absolute structure parameter	0.01 (6)

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

This work was partially supported by a Grant-in-Aid for Young Scientists (B), No. 17750032 (to MS), from the Ministry of Education, Culture, Sports, Science and Technology of Japan.

References

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