organic compounds
2-(2-Methoxyphenyl)-1H-isoindole-1,3(2H)-dione
aDepartment of Physics, University of Sargodha, Sargodha, Pakistan, and bDepartment of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com
In the title compound, C15H11NO3, the dihedral angle between the methoxybenzene and isoindole ring systems is 70.21 (3)°. The methoxy C atom is close to being coplanar with its attached ring [deviation = 0.133 (2) Å] and is oriented away from the isoindole moiety. In the crystal, inversion dimers linked by pairs of C—H⋯O hydrogen bonds generate R22(10) loops. Further C—H⋯O interactions lead to (010) infinite sheets and weak aromatic π–π stacking [centroid–centroid separations = 3.6990 (10) and 3.7217 (10) Å] is also observed.
Related literature
For related structures, see: Sim et al. (2009); Sirajuddin et al. (2012). For hydrogen-bond motifs, see: Bernstein et al., 1995).
Experimental
Crystal data
|
Refinement
|
Data collection: APEX2 (Bruker, 2007); cell 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: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON.
Supporting information
https://doi.org/10.1107/S1600536812027262/hb6857sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812027262/hb6857Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S1600536812027262/hb6857Isup3.cml
Equimolar quantities of 2-methoxyaniline and phthalic anhydride were stirred and refluxed in acetic acid for 4 h. The solution was kept at room temperature which afforded dark yellow prisms after 12 h.
The H-atoms were positioned geometrically (C–H = 0.93–0.96 Å) and refined as riding with Uiso(H) = xUeq(C), where x = 1.5 for methyl and x = 1.2 for other H-atoms.
The title compound (I), (Fig. 1) has been synthesized in an attempt to form the carboxylic acid containing methoxybenzene. We have reported the
of 1-(2-methoxyphenyl)-1H-pyrrole-2,5-dione (Sirajuddin et al., 2012) which is related to (I). The polymorph of (I) has also been published by (Sim et al., 2009).In (I), 1H-isoindole-1,3(2H)-dione A (C1—C8/N1/O1/O2) and the methoxybenzene B (C9—C15/O3) are almost planar with r.m.s. deviation of 0.0458 and 0.0320 Å, respectively. The dihedral angle between A/B is 70.21 (3)°. The molecules are dimerized due to C—H···O type of H-bonding with R22(10) ring motifs (Bernstein et al., 1995). The dimers are interlinked due to further C—H···O bonds to form infinite sheets. There exist π···π interaction between Cg1···Cg2i [i = 3/2 - x, -1/2 + y, z] and Cg2···Cg1ii [ii = 3/2 - x, 1/2 + y, z] at a distance of 3.7217 (10) Å. Similarly, there exist π···π interaction between Cg2··· Cg2i [i = 3/2 - x, -1/2 + y, z] and Cg2··· Cg2ii [ii = 3/2 - x, 1/2 + y, z] at a distance of 3.6990 (10) Å. Cg1 and Cg2 are the centroids of (C1/C2/C7/C8/N1) and (C2—C7) rings, respectively.
For related structures, see: Sim et al. (2009); Sirajuddin et al. (2012). For hydrogen-bond motifs, see: Bernstein et al., 1995).
Data collection: APEX2 (Bruker, 2007); cell
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: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).C15H11NO3 | F(000) = 1056 |
Mr = 253.25 | Dx = 1.355 Mg m−3 |
Orthorhombic, Pbca | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2ab | Cell parameters from 1816 reflections |
a = 11.5768 (6) Å | θ = 2.2–26.0° |
b = 7.3222 (5) Å | µ = 0.10 mm−1 |
c = 29.2849 (15) Å | T = 296 K |
V = 2482.4 (2) Å3 | Prism, dark yellow |
Z = 8 | 0.32 × 0.26 × 0.24 mm |
Bruker Kappa APEXII CCD diffractometer | 2428 independent reflections |
Radiation source: fine-focus sealed tube | 1816 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.024 |
Detector resolution: 8.00 pixels mm-1 | θmax = 26.0°, θmin = 2.2° |
ω scans | h = −14→14 |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | k = −9→5 |
Tmin = 0.969, Tmax = 0.977 | l = −35→36 |
10815 measured reflections |
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)] = 0.041 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.112 | H-atom parameters constrained |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0502P)2 + 0.6208P] where P = (Fo2 + 2Fc2)/3 |
2428 reflections | (Δ/σ)max < 0.001 |
173 parameters | Δρmax = 0.12 e Å−3 |
0 restraints | Δρmin = −0.17 e Å−3 |
C15H11NO3 | V = 2482.4 (2) Å3 |
Mr = 253.25 | Z = 8 |
Orthorhombic, Pbca | Mo Kα radiation |
a = 11.5768 (6) Å | µ = 0.10 mm−1 |
b = 7.3222 (5) Å | T = 296 K |
c = 29.2849 (15) Å | 0.32 × 0.26 × 0.24 mm |
Bruker Kappa APEXII CCD diffractometer | 2428 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | 1816 reflections with I > 2σ(I) |
Tmin = 0.969, Tmax = 0.977 | Rint = 0.024 |
10815 measured reflections |
R[F2 > 2σ(F2)] = 0.041 | 0 restraints |
wR(F2) = 0.112 | H-atom parameters constrained |
S = 1.03 | Δρmax = 0.12 e Å−3 |
2428 reflections | Δρmin = −0.17 e Å−3 |
173 parameters |
Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles |
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. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.45483 (10) | 0.37357 (19) | 0.07121 (4) | 0.0609 (4) | |
O2 | 0.74031 (12) | 0.1478 (2) | 0.16275 (4) | 0.0672 (5) | |
O3 | 0.41409 (11) | −0.01341 (19) | 0.11923 (4) | 0.0632 (5) | |
N1 | 0.57642 (11) | 0.2519 (2) | 0.12589 (4) | 0.0451 (4) | |
C1 | 0.54983 (14) | 0.3245 (2) | 0.08300 (5) | 0.0432 (5) | |
C2 | 0.66018 (14) | 0.3329 (2) | 0.05763 (5) | 0.0409 (5) | |
C3 | 0.68405 (17) | 0.3932 (2) | 0.01415 (6) | 0.0512 (6) | |
C4 | 0.79860 (18) | 0.3945 (3) | 0.00060 (6) | 0.0607 (6) | |
C5 | 0.88538 (17) | 0.3416 (3) | 0.02983 (7) | 0.0635 (7) | |
C6 | 0.86140 (15) | 0.2806 (2) | 0.07348 (7) | 0.0551 (6) | |
C7 | 0.74722 (14) | 0.2752 (2) | 0.08649 (5) | 0.0422 (5) | |
C8 | 0.69509 (14) | 0.2162 (2) | 0.13013 (5) | 0.0454 (5) | |
C9 | 0.49518 (15) | 0.2254 (3) | 0.16170 (5) | 0.0501 (5) | |
C10 | 0.41319 (15) | 0.0874 (3) | 0.15822 (6) | 0.0530 (6) | |
C11 | 0.33615 (18) | 0.0624 (3) | 0.19381 (7) | 0.0716 (8) | |
C12 | 0.3427 (2) | 0.1736 (4) | 0.23180 (7) | 0.0881 (9) | |
C13 | 0.4240 (2) | 0.3075 (4) | 0.23528 (7) | 0.0922 (10) | |
C14 | 0.5005 (2) | 0.3346 (3) | 0.19983 (6) | 0.0724 (8) | |
C15 | 0.3388 (2) | −0.1661 (3) | 0.11653 (9) | 0.0873 (10) | |
H3 | 0.62552 | 0.43151 | −0.00537 | 0.0615* | |
H4 | 0.81725 | 0.43190 | −0.02884 | 0.0728* | |
H5 | 0.96171 | 0.34706 | 0.02003 | 0.0762* | |
H6 | 0.92002 | 0.24465 | 0.09325 | 0.0661* | |
H11 | 0.28034 | −0.02875 | 0.19216 | 0.0860* | |
H12 | 0.29047 | 0.15681 | 0.25555 | 0.1058* | |
H13 | 0.42784 | 0.37989 | 0.26133 | 0.1107* | |
H14 | 0.55562 | 0.42669 | 0.20171 | 0.0869* | |
H15A | 0.35417 | −0.24768 | 0.14146 | 0.1309* | |
H15B | 0.35107 | −0.22876 | 0.08815 | 0.1309* | |
H15C | 0.26011 | −0.12507 | 0.11816 | 0.1309* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0466 (7) | 0.0825 (9) | 0.0537 (7) | 0.0051 (6) | −0.0098 (6) | 0.0129 (6) |
O2 | 0.0672 (8) | 0.0852 (10) | 0.0493 (7) | 0.0108 (7) | −0.0175 (6) | 0.0115 (7) |
O3 | 0.0594 (8) | 0.0663 (8) | 0.0640 (8) | −0.0159 (7) | 0.0127 (6) | −0.0053 (7) |
N1 | 0.0446 (7) | 0.0554 (8) | 0.0354 (7) | −0.0026 (6) | −0.0048 (6) | 0.0049 (6) |
C1 | 0.0469 (9) | 0.0450 (9) | 0.0377 (8) | −0.0029 (7) | −0.0084 (7) | 0.0011 (7) |
C2 | 0.0486 (9) | 0.0354 (8) | 0.0386 (8) | −0.0039 (7) | −0.0041 (7) | −0.0020 (7) |
C3 | 0.0687 (11) | 0.0425 (9) | 0.0424 (9) | −0.0034 (8) | −0.0003 (8) | 0.0020 (7) |
C4 | 0.0791 (13) | 0.0484 (10) | 0.0546 (10) | −0.0081 (10) | 0.0193 (10) | 0.0008 (9) |
C5 | 0.0580 (11) | 0.0530 (11) | 0.0794 (14) | −0.0071 (9) | 0.0204 (10) | −0.0039 (10) |
C6 | 0.0472 (10) | 0.0479 (10) | 0.0701 (12) | −0.0016 (8) | −0.0024 (9) | −0.0064 (9) |
C7 | 0.0466 (9) | 0.0350 (8) | 0.0451 (9) | −0.0031 (7) | −0.0037 (7) | −0.0049 (7) |
C8 | 0.0497 (9) | 0.0450 (9) | 0.0414 (9) | −0.0003 (7) | −0.0116 (7) | −0.0016 (7) |
C9 | 0.0507 (9) | 0.0640 (11) | 0.0356 (8) | 0.0064 (9) | −0.0014 (7) | 0.0044 (8) |
C10 | 0.0499 (10) | 0.0628 (11) | 0.0464 (9) | 0.0077 (9) | 0.0064 (8) | 0.0125 (9) |
C11 | 0.0632 (12) | 0.0882 (16) | 0.0635 (12) | 0.0137 (11) | 0.0195 (10) | 0.0266 (12) |
C12 | 0.0832 (16) | 0.131 (2) | 0.0502 (12) | 0.0392 (16) | 0.0234 (12) | 0.0282 (14) |
C13 | 0.1046 (19) | 0.131 (2) | 0.0410 (11) | 0.0330 (18) | 0.0029 (12) | −0.0085 (13) |
C14 | 0.0815 (14) | 0.0915 (16) | 0.0442 (10) | 0.0069 (12) | −0.0051 (10) | −0.0098 (10) |
C15 | 0.0696 (14) | 0.0819 (16) | 0.1103 (19) | −0.0268 (12) | 0.0106 (13) | −0.0047 (14) |
O1—C1 | 1.207 (2) | C9—C14 | 1.375 (3) |
O2—C8 | 1.199 (2) | C10—C11 | 1.384 (3) |
O3—C10 | 1.360 (2) | C11—C12 | 1.381 (3) |
O3—C15 | 1.420 (3) | C12—C13 | 1.363 (4) |
N1—C1 | 1.3982 (19) | C13—C14 | 1.379 (3) |
N1—C8 | 1.404 (2) | C3—H3 | 0.9300 |
N1—C9 | 1.422 (2) | C4—H4 | 0.9300 |
C1—C2 | 1.479 (2) | C5—H5 | 0.9300 |
C2—C3 | 1.376 (2) | C6—H6 | 0.9300 |
C2—C7 | 1.381 (2) | C11—H11 | 0.9300 |
C3—C4 | 1.384 (3) | C12—H12 | 0.9300 |
C4—C5 | 1.376 (3) | C13—H13 | 0.9300 |
C5—C6 | 1.382 (3) | C14—H14 | 0.9300 |
C6—C7 | 1.376 (2) | C15—H15A | 0.9600 |
C7—C8 | 1.478 (2) | C15—H15B | 0.9600 |
C9—C10 | 1.390 (3) | C15—H15C | 0.9600 |
C10—O3—C15 | 118.01 (16) | C10—C11—C12 | 119.6 (2) |
C1—N1—C8 | 111.45 (12) | C11—C12—C13 | 121.5 (2) |
C1—N1—C9 | 124.67 (13) | C12—C13—C14 | 119.4 (2) |
C8—N1—C9 | 123.82 (13) | C9—C14—C13 | 119.9 (2) |
O1—C1—N1 | 124.79 (14) | C2—C3—H3 | 121.00 |
O1—C1—C2 | 129.10 (14) | C4—C3—H3 | 121.00 |
N1—C1—C2 | 106.07 (13) | C3—C4—H4 | 119.00 |
C1—C2—C3 | 130.67 (15) | C5—C4—H4 | 119.00 |
C1—C2—C7 | 108.06 (13) | C4—C5—H5 | 119.00 |
C3—C2—C7 | 121.19 (16) | C6—C5—H5 | 119.00 |
C2—C3—C4 | 117.39 (17) | C5—C6—H6 | 121.00 |
C3—C4—C5 | 121.29 (17) | C7—C6—H6 | 121.00 |
C4—C5—C6 | 121.32 (18) | C10—C11—H11 | 120.00 |
C5—C6—C7 | 117.27 (17) | C12—C11—H11 | 120.00 |
C2—C7—C6 | 121.50 (15) | C11—C12—H12 | 119.00 |
C2—C7—C8 | 108.70 (14) | C13—C12—H12 | 119.00 |
C6—C7—C8 | 129.79 (15) | C12—C13—H13 | 120.00 |
O2—C8—N1 | 125.14 (15) | C14—C13—H13 | 120.00 |
O2—C8—C7 | 129.26 (15) | C9—C14—H14 | 120.00 |
N1—C8—C7 | 105.59 (12) | C13—C14—H14 | 120.00 |
N1—C9—C10 | 119.79 (15) | O3—C15—H15A | 110.00 |
N1—C9—C14 | 119.34 (18) | O3—C15—H15B | 109.00 |
C10—C9—C14 | 120.86 (16) | O3—C15—H15C | 109.00 |
O3—C10—C9 | 116.81 (15) | H15A—C15—H15B | 109.00 |
O3—C10—C11 | 124.44 (18) | H15A—C15—H15C | 109.00 |
C9—C10—C11 | 118.75 (17) | H15B—C15—H15C | 109.00 |
C15—O3—C10—C9 | 174.12 (17) | C3—C2—C7—C6 | 1.9 (2) |
C15—O3—C10—C11 | −6.5 (3) | C3—C2—C7—C8 | −179.07 (14) |
C8—N1—C1—O1 | −177.05 (15) | C2—C3—C4—C5 | −1.5 (3) |
C8—N1—C1—C2 | 0.97 (17) | C3—C4—C5—C6 | 1.7 (3) |
C9—N1—C1—O1 | 0.1 (3) | C4—C5—C6—C7 | −0.1 (3) |
C9—N1—C1—C2 | 178.09 (16) | C5—C6—C7—C2 | −1.7 (2) |
C1—N1—C8—O2 | −177.22 (15) | C5—C6—C7—C8 | 179.52 (17) |
C1—N1—C8—C7 | 1.25 (17) | C2—C7—C8—O2 | 175.22 (16) |
C9—N1—C8—O2 | 5.6 (3) | C2—C7—C8—N1 | −3.16 (16) |
C9—N1—C8—C7 | −175.90 (15) | C6—C7—C8—O2 | −5.9 (3) |
C1—N1—C9—C10 | 71.9 (2) | C6—C7—C8—N1 | 175.74 (15) |
C1—N1—C9—C14 | −109.5 (2) | N1—C9—C10—O3 | −1.6 (3) |
C8—N1—C9—C10 | −111.38 (19) | N1—C9—C10—C11 | 179.02 (17) |
C8—N1—C9—C14 | 67.2 (3) | C14—C9—C10—O3 | 179.80 (18) |
O1—C1—C2—C3 | −1.9 (3) | C14—C9—C10—C11 | 0.4 (3) |
O1—C1—C2—C7 | 174.92 (16) | N1—C9—C14—C13 | −178.45 (19) |
N1—C1—C2—C3 | −179.77 (16) | C10—C9—C14—C13 | 0.2 (3) |
N1—C1—C2—C7 | −2.98 (16) | O3—C10—C11—C12 | −179.6 (2) |
C1—C2—C3—C4 | 176.14 (17) | C9—C10—C11—C12 | −0.3 (3) |
C7—C2—C3—C4 | −0.3 (2) | C10—C11—C12—C13 | −0.4 (4) |
C1—C2—C7—C6 | −175.24 (14) | C11—C12—C13—C14 | 1.0 (4) |
C1—C2—C7—C8 | 3.77 (17) | C12—C13—C14—C9 | −0.8 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
C3—H3···O1i | 0.93 | 2.57 | 3.428 (2) | 153 |
C12—H12···O2ii | 0.93 | 2.46 | 3.313 (2) | 152 |
Symmetry codes: (i) −x+1, −y+1, −z; (ii) x−1/2, y, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C15H11NO3 |
Mr | 253.25 |
Crystal system, space group | Orthorhombic, Pbca |
Temperature (K) | 296 |
a, b, c (Å) | 11.5768 (6), 7.3222 (5), 29.2849 (15) |
V (Å3) | 2482.4 (2) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.32 × 0.26 × 0.24 |
Data collection | |
Diffractometer | Bruker Kappa APEXII CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2005) |
Tmin, Tmax | 0.969, 0.977 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10815, 2428, 1816 |
Rint | 0.024 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.041, 0.112, 1.03 |
No. of reflections | 2428 |
No. of parameters | 173 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.12, −0.17 |
Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
C3—H3···O1i | 0.93 | 2.57 | 3.428 (2) | 153 |
C12—H12···O2ii | 0.93 | 2.46 | 3.313 (2) | 152 |
Symmetry codes: (i) −x+1, −y+1, −z; (ii) x−1/2, y, −z+1/2. |
Acknowledgements
The authors acknowledge the provision of funds for the purchase of a diffractometer and encouragement by Dr Muhammad Akram Chaudhary, Vice Chancellor, University of Sargodha, Pakistan.
References
Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573. CrossRef CAS Web of Science Google Scholar
Bruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838. CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Sim, Y. L., Ariffin, A., Khan, M. N. & Ng, S. W. (2009). Acta Cryst. E65, o2218. Web of Science CSD CrossRef IUCr Journals Google Scholar
Sirajuddin, M., Ali, S. & Tahir, M. N. (2012). Acta Cryst. E68, o2282. CSD CrossRef IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
The title compound (I), (Fig. 1) has been synthesized in an attempt to form the carboxylic acid containing methoxybenzene. We have reported the crystal structure of 1-(2-methoxyphenyl)-1H-pyrrole-2,5-dione (Sirajuddin et al., 2012) which is related to (I). The polymorph of (I) has also been published by (Sim et al., 2009).
In (I), 1H-isoindole-1,3(2H)-dione A (C1—C8/N1/O1/O2) and the methoxybenzene B (C9—C15/O3) are almost planar with r.m.s. deviation of 0.0458 and 0.0320 Å, respectively. The dihedral angle between A/B is 70.21 (3)°. The molecules are dimerized due to C—H···O type of H-bonding with R22(10) ring motifs (Bernstein et al., 1995). The dimers are interlinked due to further C—H···O bonds to form infinite sheets. There exist π···π interaction between Cg1···Cg2i [i = 3/2 - x, -1/2 + y, z] and Cg2···Cg1ii [ii = 3/2 - x, 1/2 + y, z] at a distance of 3.7217 (10) Å. Similarly, there exist π···π interaction between Cg2··· Cg2i [i = 3/2 - x, -1/2 + y, z] and Cg2··· Cg2ii [ii = 3/2 - x, 1/2 + y, z] at a distance of 3.6990 (10) Å. Cg1 and Cg2 are the centroids of (C1/C2/C7/C8/N1) and (C2—C7) rings, respectively.