3-Nitro-1-(triisopropyl­silyl)-1H-pyrrole

Kennedy, A.R.; Khalaf, A.I.; Suckling, C.J.; Waigh, R.D.

doi:10.1107/S1600536806025943

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 62| Part 8| August 2006| Pages o3282-o3284

https://doi.org/10.1107/S1600536806025943

3-Nitro-1-(triisopropylsilyl)-1H-pyrrole

Alan R. Kennedy,^a ^* Abedawn I. Khalaf,^a Colin J. Suckling ^a and Roger D. Waigh ^b

^aWestCHEM, Department of Pure & Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, Scotland, and ^bDepartment of Pharmaceutical Sciences, University of Strathclyde, 27 Taylor Street, Glasgow G4 0NR, Scotland
^*Correspondence e-mail: a.r.kennedy@strath.ac.uk

(Received 29 June 2006; accepted 5 July 2006; online 12 July 2006)

The nitration of 1-(triisopropylsilyl)-1H-pyrrole leads to a mixture of products following partial acid cleavage of the triisopropylsilyl protecting group. Structural determination showed the isolated products to be the title compound, C₁₃H₂₄N₂2O₂Si, and 2,4-dinitropyrrole. In the solid state, the title compound exists as discrete molecules with only weak C—H⋯nitro hydrogen bonds between them.

Comment

The quest for N-alkyl-substituted pyrroles bearing a nitro group at position three has led us to the use of the cleavable and bulky triisoproplysilyl (TIPS) group. This work is in connection with our research into minor-groove binding compounds (Khalaf et al., 2004 ). These compounds are analogues of naturally occurring distamycin and netropsin, which bind primarily to the adenine-thymine-rich minor groove of DNA. 3-Nitropyrrole (Bray et al., 1990 ) was required as a precursor; however, the straightforward nitration of pyrrole favours position two. To prevent the nitration from occurring at position two of the pyrrole, a TIPS protecting group was first attached to the nitrogen of the pyrrole ring. This led to the nitro group being directed to position three (as anticipated), giving rise to the desired product (I) (Fig. 1) in 32% yield. However, during the course of the reaction, and due to the presence of acetic acid, the TIPS group cleaved. The removal of the TIPS group allowed the nitration reaction to occur once again. However, this time it occurred at position two, leading to the formation of the undesired product, 2,4-dinitropyrrole (II), in 19% yield.

Despite the large number of substituted pyrroles reported in the Cambridge Structural Database (Version 5.27 with updates to May 2006; Allen, 2002 ), a search found only nine relevant 3-nitro derivatives. All of the ring bond lengths and angles (Table 1) of (I) fall within the ranges found for these nine structures, with the exception that in (I) the C2—N1—C5 angle is slightly below the literature range [106.8 (2)° cf. 107.7–110.2°]. This is presumably due to the bulk and inductive effects of the attached TIPS group as no such relevant N-silyl substituent was found in the database. All of the literature nitro groups are approximately coplanar with their pyrrole rings; it can be seen from Table 1 that this is also the case for (I).

In the absence of obvious hydrogen-bonding groups, nitro aromatics often display nitro-to-nitro interactions of the type described by Wozniak et al. (1994 ); however, none is found in (I). The only intermolecular interactions of any note are weak C—H⋯O contacts utilizing both sp² and sp³ CH groups (see Table 2). This can be rationalized as a consequence of the bulky triisopropylsilyl group, which ensures that the ring systems are widely separated from each other.

Figure 1
The molecular structure of (I)

, with displacement ellipsoids drawn at the 50% probability level.

Experimental

A solution of cupric nitrate trihydrate (2.70 g, 11.2 mmol) in acetic anhydride (20 ml) was cooled to 273 K and 1-(triisopropylsilyl)-1H-pyrrole (2.50 g, 11.2 mmol) was added dropwise with stirring. The ice bath was removed and stirring was continued for 1 h at room temperature. The reaction mixture was poured slowly over a saturated sodium hydrogen carbonate solution with stirring. After extraction with diethyl ether the organic layer was collected, dried (MgSO₄) and the solvent was removed under reduced pressure. The residue was subjected to flash chromatography on silica gel, using ethyl acetate/hexane (1:12) to elute (I). The solvents were removed under reduced pressure and a slow stream of air was passed over the residue to remove any volatile material. The product was obtained as colourless crystals [0.947 g, 32%; m.p. 325–327 K, literature m.p. 325–327 K (Bray et al., 1990)]. Compound (II) was eluted using ethyl acetate–hexane (1:4). This material was obtained, after the removal of the solvents, as pale-yellow crystals [0.338 g, 19%; m.p. 422–423 K, literature m.p. 423–424 K (Sharnin et al., 1975 )].

Crystal data

C₁₃H₂₄N₂O₂Si
M_r = 268.43
Monoclinic, P 2₁ /n
a = 9.6924 (5) Å
b = 15.9437 (10) Å
c = 10.1267 (6) Å
β = 95.089 (4)°
V = 1558.74 (16) Å³
Z = 4
D_x = 1.144 Mg m⁻³
Mo Kα radiation
μ = 0.15 mm⁻¹
T = 123 (2) K
Cut fragment, colourless
0.30 × 0.12 × 0.08 mm

Data collection

Nonius KappaCCD diffractometer
ω and φ scans
Absorption correction: none
13088 measured reflections
3060 independent reflections
1685 reflections with I > 2σ(I)
R_int = 0.108
θ_max = 26.0°

Refinement

Refinement on F²
R[F² > 2σ(F²)] = 0.059
wR(F²) = 0.123
S = 1.01
3060 reflections
169 parameters
H-atom parameters constrained
w = 1/[σ²(F_o²) + (0.0471P)² + 0.0035P] where P = (F_o² + 2F_c²)/3
(Δ/σ)_max = 0.001
Δρ_max = 0.34 e Å⁻³
Δρ_min = −0.36 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Si1—N1	1.805 (2)
N1—C2	1.365 (3)
N1—C5	1.395 (3)
C2—C3	1.365 (3)
C3—C4	1.410 (4)
C4—C5	1.358 (4)

C2—N1—C5	106.8 (2)
C3—C2—N1	108.4 (2)
C2—C3—C4	109.1 (2)
C5—C4—C3	105.3 (2)
C4—C5—N1	110.3 (2)

O1—N2—C3—C2	−0.5 (4)
O2—N2—C3—C2	178.9 (2)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C5—H5⋯O2ⁱ	0.95	2.47	3.403 (4)	166
C10—H10⋯O1ⁱⁱ	1.00	2.55	3.245 (4)	126
Symmetry codes: (i) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (ii) -x+1, -y, -z.

All H atoms were positioned geometrically, C—H = 0.95 (Csp²), 0.98 (CH₃) or 1.00 Å (Csp³), and refined using a riding model [U_iso(H) = 1.5U_eq(C) for CH₃ and 1.2U_eq(C) for all others].

Data collection: COLLECT (Hooft, 1988 ) and DENZO (Otwinowski & Minor, 1997 ); cell refinement: DENZO and COLLECT; data reduction: DENZO; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536806025943/fl2035sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536806025943/fl2035Isup2.hkl

Computing details top

Data collection: COLLECT (Hooft, 1988) and DENZO (Otwinowski & Minor, 1997); cell refinement: DENZO and COLLECT; data reduction: DENZO; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97.

3-Nitro-1-(triisopropylsilyl)-1H-pyrrole top

Crystal data top

C₁₃H₂₄N₂O₂Si	F(000) = 584
M_r = 268.43	D_x = 1.144 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
a = 9.6924 (5) Å	Cell parameters from 3020 reflections
b = 15.9437 (10) Å	θ = 1.0–26.1°
c = 10.1267 (6) Å	µ = 0.15 mm⁻¹
β = 95.089 (4)°	T = 123 K
V = 1558.74 (16) Å³	Cut fragment, colourless
Z = 4	0.30 × 0.12 × 0.08 mm

Data collection top

Nonius KappaCCD diffractometer	1685 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.108
Graphite monochromator	θ_max = 26.0°, θ_min = 2.4°
ω and φ scans	h = −11→11
13088 measured reflections	k = −19→19
3060 independent reflections	l = −12→12

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)] = 0.059	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.123	H-atom parameters constrained
S = 1.01	w = 1/[σ²(F_o²) + (0.0471P)² + 0.0035P] where P = (F_o² + 2F_c²)/3
3060 reflections	(Δ/σ)_max = 0.001
169 parameters	Δρ_max = 0.34 e Å⁻³
0 restraints	Δρ_min = −0.36 e Å⁻³

Special details top

Experimental. A solution of cupric nitrate trihydrate (2.70 g, 11.2 mmol) in acetic anhydride (20 ml) was cooled to 273 K and 1-(triisopropylsilyl)-1H-pyrrole (2.50 g, 11.2 mmol) was added dropwise with stirring. The ice bath was removed and stirring was continued for 1 h at room temperature. The reaction mixture was poured slowly over a saturated sodium hydrogen carbonate solution with stirring. After extraction with ether the organic layer was collected, dried (MgSO₄) and the solvent was removed under reduced pressure. The residue was subjected to flash chromatography on silica gel, using ethyl acetate/hexane (1:12) to elute (I). The solvents were removed under reduced pressure and a slow stream of air was passed over it to remove any volatile material. The product was obtained as colourless crystals [0.947 g, 32%; m.p. 325–327 K, literature m.p. 325–327 K (Bray et al., 1990)]. ¹H NMR (DMSO-d₆): δ 7.88 (1H, dd, J = 2.6, 5.4 Hz), 6.88 (1H, dd, J = 3.9, 7.8 Hz), 6.67 (1H, dd, J = 3.9, 6.4 Hz), 1.05–0.86 (21H, m). IR (KBr): 1550, 1330, 1240 cm^-1. Compound (II) was eluted using ethyl acetate–hexane (1:4). This material was obtained, after the removal of the solvents, as pale-yellow crystals [0.338 g, 19%; m.p. 422–423 K, literature m.p. 423–424 K (Sharnin et al., 1975)]. ¹H NMR (DMSO-d₆): δ 14.4 (1H, br), 8.26 (1H, d, J = 2.9 Hz), 7.71 (1H, d, J = 2.9 Hz). IR (KBr): 3195, 3153, 1554, 1488, 1347, 1239, 1124, 1080, 957, 846, 815, 751 cm^-1.

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
Si1	0.84500 (8)	0.11350 (5)	0.27816 (7)	0.0205 (2)
O1	0.5558 (2)	0.07380 (14)	−0.21907 (19)	0.0418 (6)
O2	0.6482 (2)	0.17835 (13)	−0.31778 (19)	0.0346 (6)
N1	0.8022 (2)	0.15042 (14)	0.1111 (2)	0.0215 (6)
N2	0.6353 (2)	0.13427 (17)	−0.2192 (2)	0.0287 (6)
C2	0.7113 (3)	0.11329 (18)	0.0182 (3)	0.0217 (7)
H2	0.6543	0.0662	0.0326	0.026*
C3	0.7160 (3)	0.15521 (17)	−0.0989 (3)	0.0211 (7)
C4	0.8127 (3)	0.22120 (18)	−0.0811 (3)	0.0252 (7)
H4	0.8369	0.2605	−0.1456	0.030*
C5	0.8639 (3)	0.21657 (18)	0.0480 (3)	0.0249 (7)
H5	0.9321	0.2531	0.0893	0.030*
C6	0.9494 (3)	−0.03860 (18)	0.1823 (3)	0.0342 (8)
H6A	0.9218	−0.0196	0.0917	0.051*
H6B	0.8714	−0.0675	0.2177	0.051*
H6C	1.0280	−0.0772	0.1814	0.051*
C7	0.9916 (3)	0.03755 (17)	0.2703 (3)	0.0220 (7)
H7	1.0150	0.0159	0.3622	0.026*
C8	1.1233 (3)	0.07824 (19)	0.2257 (3)	0.0327 (8)
H8A	1.1960	0.0357	0.2233	0.049*
H8B	1.1547	0.1226	0.2883	0.049*
H8C	1.1033	0.1024	0.1371	0.049*
C9	0.5574 (3)	0.11509 (19)	0.3264 (3)	0.0314 (8)
H9A	0.4739	0.0804	0.3265	0.047*
H9B	0.5495	0.1518	0.2485	0.047*
H9C	0.5673	0.1493	0.4070	0.047*
C10	0.6848 (3)	0.05834 (17)	0.3218 (3)	0.0216 (7)
H10	0.6610	0.0173	0.2487	0.026*
C11	0.7071 (3)	0.00593 (18)	0.4497 (3)	0.0309 (8)
H11A	0.7244	0.0434	0.5260	0.046*
H11B	0.7869	−0.0313	0.4442	0.046*
H11C	0.6242	−0.0277	0.4602	0.046*
C12	0.7990 (3)	0.28032 (18)	0.3786 (3)	0.0412 (9)
H12A	0.7233	0.2635	0.4309	0.062*
H12B	0.7618	0.2932	0.2878	0.062*
H12C	0.8448	0.3301	0.4186	0.062*
C13	0.9040 (3)	0.20860 (17)	0.3765 (3)	0.0239 (7)
H13	0.9839	0.2318	0.3322	0.029*
C14	0.9625 (3)	0.18556 (18)	0.5188 (3)	0.0323 (8)
H14A	1.0043	0.2354	0.5627	0.049*
H14B	1.0330	0.1417	0.5152	0.049*
H14C	0.8873	0.1650	0.5688	0.049*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Si1	0.0208 (4)	0.0213 (5)	0.0190 (4)	−0.0002 (4)	0.0003 (3)	0.0005 (4)
O1	0.0396 (14)	0.0471 (15)	0.0365 (13)	−0.0144 (12)	−0.0085 (10)	−0.0055 (12)
O2	0.0399 (13)	0.0426 (14)	0.0211 (12)	0.0074 (11)	0.0013 (10)	0.0046 (11)
N1	0.0226 (14)	0.0214 (14)	0.0201 (13)	−0.0030 (11)	0.0001 (11)	0.0005 (11)
N2	0.0252 (15)	0.0341 (17)	0.0266 (16)	0.0064 (13)	0.0012 (12)	−0.0037 (14)
C2	0.0213 (15)	0.0185 (16)	0.0252 (17)	−0.0006 (13)	0.0016 (13)	0.0001 (14)
C3	0.0181 (15)	0.0250 (17)	0.0196 (16)	0.0021 (14)	−0.0016 (13)	−0.0022 (14)
C4	0.0249 (17)	0.0266 (18)	0.0240 (17)	−0.0008 (14)	0.0016 (13)	0.0089 (14)
C5	0.0255 (17)	0.0221 (17)	0.0265 (18)	−0.0072 (14)	−0.0013 (13)	0.0022 (14)
C6	0.0292 (18)	0.032 (2)	0.0413 (19)	0.0012 (15)	0.0048 (15)	−0.0053 (16)
C7	0.0214 (16)	0.0232 (18)	0.0212 (16)	−0.0009 (13)	0.0003 (13)	−0.0001 (13)
C8	0.0249 (18)	0.0315 (18)	0.042 (2)	0.0011 (15)	0.0029 (15)	−0.0052 (16)
C9	0.0233 (17)	0.037 (2)	0.0343 (18)	0.0037 (15)	0.0059 (13)	0.0060 (16)
C10	0.0232 (16)	0.0233 (17)	0.0185 (16)	−0.0003 (14)	0.0026 (12)	0.0014 (13)
C11	0.0304 (17)	0.0294 (19)	0.0334 (18)	−0.0001 (15)	0.0063 (14)	0.0045 (15)
C12	0.051 (2)	0.0266 (19)	0.045 (2)	0.0056 (17)	−0.0019 (17)	−0.0090 (17)
C13	0.0276 (17)	0.0208 (17)	0.0238 (16)	−0.0011 (14)	0.0046 (13)	0.0000 (14)
C14	0.0415 (19)	0.0307 (19)	0.0240 (17)	−0.0020 (15)	−0.0016 (15)	−0.0024 (15)

Geometric parameters (Å, º) top

Si1—N1	1.805 (2)	C8—H8A	0.9800
Si1—C10	1.871 (3)	C8—H8B	0.9800
Si1—C7	1.874 (3)	C8—H8C	0.9800
Si1—C13	1.876 (3)	C9—C10	1.535 (4)
O1—N2	1.234 (3)	C9—H9A	0.9800
O2—N2	1.237 (3)	C9—H9B	0.9800
N1—C2	1.365 (3)	C9—H9C	0.9800
N1—C5	1.395 (3)	C10—C11	1.540 (4)
N2—C3	1.428 (3)	C10—H10	1.0000
C2—C3	1.365 (3)	C11—H11A	0.9800
C2—H2	0.9500	C11—H11B	0.9800
C3—C4	1.410 (4)	C11—H11C	0.9800
C4—C5	1.358 (4)	C12—C13	1.532 (4)
C4—H4	0.9500	C12—H12A	0.9800
C5—H5	0.9500	C12—H12B	0.9800
C6—C7	1.540 (4)	C12—H12C	0.9800
C6—H6A	0.9800	C13—C14	1.545 (4)
C6—H6B	0.9800	C13—H13	1.0000
C6—H6C	0.9800	C14—H14A	0.9800
C7—C8	1.535 (3)	C14—H14B	0.9800
C7—H7	1.0000	C14—H14C	0.9800

N1—Si1—C10	104.37 (11)	C7—C8—H8C	109.5
N1—Si1—C7	106.44 (11)	H8A—C8—H8C	109.5
C10—Si1—C7	110.77 (12)	H8B—C8—H8C	109.5
N1—Si1—C13	105.56 (11)	C10—C9—H9A	109.5
C10—Si1—C13	118.35 (12)	C10—C9—H9B	109.5
C7—Si1—C13	110.39 (12)	H9A—C9—H9B	109.5
C2—N1—C5	106.8 (2)	C10—C9—H9C	109.5
C2—N1—Si1	125.80 (18)	H9A—C9—H9C	109.5
C5—N1—Si1	127.14 (18)	H9B—C9—H9C	109.5
O1—N2—O2	123.5 (2)	C9—C10—C11	110.4 (2)
O1—N2—C3	118.5 (2)	C9—C10—Si1	114.63 (19)
O2—N2—C3	118.0 (3)	C11—C10—Si1	113.34 (18)
C3—C2—N1	108.4 (2)	C9—C10—H10	105.9
C3—C2—H2	125.8	C11—C10—H10	105.9
N1—C2—H2	125.8	Si1—C10—H10	105.9
C2—C3—C4	109.1 (2)	C10—C11—H11A	109.5
C2—C3—N2	124.6 (3)	C10—C11—H11B	109.5
C4—C3—N2	126.3 (3)	H11A—C11—H11B	109.5
C5—C4—C3	105.3 (2)	C10—C11—H11C	109.5
C5—C4—H4	127.3	H11A—C11—H11C	109.5
C3—C4—H4	127.3	H11B—C11—H11C	109.5
C4—C5—N1	110.3 (2)	C13—C12—H12A	109.5
C4—C5—H5	124.9	C13—C12—H12B	109.5
N1—C5—H5	124.9	H12A—C12—H12B	109.5
C7—C6—H6A	109.5	C13—C12—H12C	109.5
C7—C6—H6B	109.5	H12A—C12—H12C	109.5
H6A—C6—H6B	109.5	H12B—C12—H12C	109.5
C7—C6—H6C	109.5	C12—C13—C14	110.7 (2)
H6A—C6—H6C	109.5	C12—C13—Si1	116.03 (19)
H6B—C6—H6C	109.5	C14—C13—Si1	111.87 (19)
C8—C7—C6	110.4 (2)	C12—C13—H13	105.8
C8—C7—Si1	113.14 (19)	C14—C13—H13	105.8
C6—C7—Si1	111.76 (18)	Si1—C13—H13	105.8
C8—C7—H7	107.1	C13—C14—H14A	109.5
C6—C7—H7	107.1	C13—C14—H14B	109.5
Si1—C7—H7	107.1	H14A—C14—H14B	109.5
C7—C8—H8A	109.5	C13—C14—H14C	109.5
C7—C8—H8B	109.5	H14A—C14—H14C	109.5
H8A—C8—H8B	109.5	H14B—C14—H14C	109.5

C10—Si1—N1—C2	−29.4 (2)	N1—Si1—C7—C8	63.3 (2)
C7—Si1—N1—C2	87.8 (2)	C10—Si1—C7—C8	176.16 (18)
C13—Si1—N1—C2	−154.9 (2)	C13—Si1—C7—C8	−50.8 (2)
C10—Si1—N1—C5	157.3 (2)	N1—Si1—C7—C6	−62.1 (2)
C7—Si1—N1—C5	−85.5 (2)	C10—Si1—C7—C6	50.8 (2)
C13—Si1—N1—C5	31.8 (2)	C13—Si1—C7—C6	−176.13 (18)
C5—N1—C2—C3	−0.2 (3)	N1—Si1—C10—C9	−64.0 (2)
Si1—N1—C2—C3	−174.65 (18)	C7—Si1—C10—C9	−178.14 (19)
N1—C2—C3—C4	0.0 (3)	C13—Si1—C10—C9	53.0 (2)
N1—C2—C3—N2	179.8 (2)	N1—Si1—C10—C11	168.10 (19)
O1—N2—C3—C2	−0.5 (4)	C7—Si1—C10—C11	53.9 (2)
O2—N2—C3—C2	178.9 (2)	C13—Si1—C10—C11	−75.0 (2)
O1—N2—C3—C4	179.3 (3)	N1—Si1—C13—C12	59.0 (2)
O2—N2—C3—C4	−1.3 (4)	C10—Si1—C13—C12	−57.3 (2)
C2—C3—C4—C5	0.2 (3)	C7—Si1—C13—C12	173.6 (2)
N2—C3—C4—C5	−179.6 (2)	N1—Si1—C13—C14	−172.69 (18)
C3—C4—C5—N1	−0.3 (3)	C10—Si1—C13—C14	71.0 (2)
C2—N1—C5—C4	0.3 (3)	C7—Si1—C13—C14	−58.1 (2)
Si1—N1—C5—C4	174.66 (19)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···O2ⁱ	0.95	2.47	3.403 (4)	166
C10—H10···O1ⁱⁱ	1.00	2.55	3.245 (4)	126

Symmetry codes: (i) x+1/2, −y+1/2, z+1/2; (ii) −x+1, −y, −z.

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