organic compounds
Ethyl 2-[2-(2-methoxyphenyl)hydrazinylidene]-3-oxobutanoate
aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri, Mangalore 574 199, India
*Correspondence e-mail: hkfun@usm.my
In the title compound, C13H16N2O4, an intramolecular N—H⋯O hydrogen bond generates an S(6) ring. The molecule adopts an E configuration with respect to the central C=N double bond. In the crystal, symmetry-related molecules are connected into chains along [010] via weak C—H⋯N hydrogen bonds. The is further stabilized by weak C—H⋯π interactions.
Related literature
For details and applications of pyrazole derivatives, see: Rai et al. (2008); Girisha et al. (2010); Isloor et al. (2009). For hydrogen-bond motifs, see: Bernstein et al. (1995). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).
Experimental
Crystal data
|
Refinement
|
Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009).
Supporting information
https://doi.org/10.1107/S1600536811034854/lh5322sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811034854/lh5322Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S1600536811034854/lh5322Isup3.cml
The title compound was prepared by dissolving 2-methoxy aniline (0.01 mol) in dilute hydrochloric acid (10 ml) and cooled to 273K in an ice bath. To this, a cold solution of sodium nitrite (0.02 mol) was added. The resulting diazonium salt solution was filtered into a cold solution of ethyl acetoacetate (0.05 mol) and sodium acetate in ethanol. The separated yellow solid was filtered, washed with water and recrystallized from ethanol. Crystals suitable for X-ray analysis were obtained by slow evaporationfrom of a solution of (I) in a 1:2 mixture of DMF and ethanol.
Atom H1N1 was located in a difference Fourier map and refined freely [N–H = 0.898 (17) Å]. The remaining H atoms were positioned geometrically [C–H = 0.93–0.97 Å] and were refined using a riding model, with Uiso(H) = 1.2 or 1.5 Ueq(C). A rotating group model was applied to the methyl groups.
Pyrazole derivatives are well established in the literature as important biologically effective
(Rai et al., 2008). These derivatives are the subject of many research studies due to their widespread potential pharmacological activities such as antiinflammatory (Girisha et al., 2010), antipyretic, antimicrobial (Isloor et al., 2009) and antiviral activities. The widely prescribed anti-inflammatory pyrazole derivatives, celecoxib and deracoxib, are selective COX-2 inhibitors with reduced ulcerogenic side effects. The title compound, ethyl-2-[(2-methoxyphenyl) hydrazinylidene]-3-oxobutanoate is a key intermediate in the preparation of pyrazole derivative which in turn was obtained by the condensation of 2-[(2-substituted phenyl)hydrazinylidene]-3-oxobutanoate with thiosemicarbazide in glacial acetic acid medium.Fig. 1 shows the molecular structure of the title compound (I). The molecule adopts an E-configuration with respect to the central C6═N1 double bond. An intramolecular N1—H1N1···O3 interaction generates an S(6) ring (Bernstein et al., 1995). In the crystal, (Fig. 2), adjacent molecules are interconnected into one-dimensional chains along [010] via intermolecular C13—H13C···N2i hydrogen bonds. Furthermore, the is stabilized by C—H···π interactions (Table 1) involving the C1–C6 (centroid Cg1) ring.
For details and applications of pyrazole derivatives, see: Rai et al. (2008); Girisha et al. (2010); Isloor et al. (2009). For hydrogen-bond motifs, see: Bernstein et al. (1995). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).
Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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 and PLATON (Spek, 2009).C13H16N2O4 | F(000) = 560 |
Mr = 264.28 | Dx = 1.306 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 7354 reflections |
a = 10.1885 (4) Å | θ = 2.5–30.8° |
b = 11.4967 (4) Å | µ = 0.10 mm−1 |
c = 13.2492 (5) Å | T = 100 K |
β = 120.003 (3)° | Needle, green |
V = 1343.97 (9) Å3 | 0.75 × 0.27 × 0.20 mm |
Z = 4 |
Bruker SMART APEXII CCD area-detector diffractometer | 3909 independent reflections |
Radiation source: fine-focus sealed tube | 3123 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.028 |
φ and ω scans | θmax = 30.0°, θmin = 2.3° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −14→13 |
Tmin = 0.931, Tmax = 0.981 | k = −16→16 |
14963 measured reflections | l = −14→18 |
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)] = 0.044 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.116 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0513P)2 + 0.4458P] where P = (Fo2 + 2Fc2)/3 |
3909 reflections | (Δ/σ)max < 0.001 |
179 parameters | Δρmax = 0.35 e Å−3 |
0 restraints | Δρmin = −0.30 e Å−3 |
C13H16N2O4 | V = 1343.97 (9) Å3 |
Mr = 264.28 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 10.1885 (4) Å | µ = 0.10 mm−1 |
b = 11.4967 (4) Å | T = 100 K |
c = 13.2492 (5) Å | 0.75 × 0.27 × 0.20 mm |
β = 120.003 (3)° |
Bruker SMART APEXII CCD area-detector diffractometer | 3909 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 3123 reflections with I > 2σ(I) |
Tmin = 0.931, Tmax = 0.981 | Rint = 0.028 |
14963 measured reflections |
R[F2 > 2σ(F2)] = 0.044 | 0 restraints |
wR(F2) = 0.116 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.35 e Å−3 |
3909 reflections | Δρmin = −0.30 e Å−3 |
179 parameters |
Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K. |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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 | 0.30643 (9) | 0.58032 (7) | 0.53563 (7) | 0.02056 (18) | |
O2 | 0.61515 (9) | 0.07478 (7) | 0.68475 (7) | 0.01987 (18) | |
O3 | 0.76423 (9) | 0.37484 (7) | 0.73708 (7) | 0.02157 (19) | |
O4 | 0.51710 (10) | 0.68753 (7) | 0.63602 (7) | 0.02266 (19) | |
N1 | 0.49890 (11) | 0.28280 (8) | 0.62667 (8) | 0.01539 (19) | |
N2 | 0.44571 (10) | 0.38868 (8) | 0.60104 (8) | 0.01477 (19) | |
C1 | 0.24246 (12) | 0.20271 (10) | 0.51384 (9) | 0.0164 (2) | |
H1A | 0.2010 | 0.2769 | 0.4937 | 0.020* | |
C2 | 0.14890 (13) | 0.10570 (10) | 0.47404 (10) | 0.0188 (2) | |
H2A | 0.0447 | 0.1147 | 0.4267 | 0.023* | |
C3 | 0.21166 (13) | −0.00471 (10) | 0.50522 (10) | 0.0193 (2) | |
H3A | 0.1486 | −0.0695 | 0.4788 | 0.023* | |
C4 | 0.36743 (13) | −0.02020 (10) | 0.57532 (10) | 0.0182 (2) | |
H4A | 0.4082 | −0.0946 | 0.5955 | 0.022* | |
C5 | 0.46119 (12) | 0.07678 (9) | 0.61481 (9) | 0.0155 (2) | |
C6 | 0.39815 (12) | 0.18864 (9) | 0.58381 (9) | 0.0149 (2) | |
C7 | 0.53715 (12) | 0.47955 (9) | 0.63721 (9) | 0.0154 (2) | |
C8 | 0.45682 (13) | 0.59306 (9) | 0.60453 (9) | 0.0160 (2) | |
C9 | 0.21993 (13) | 0.68756 (10) | 0.50635 (10) | 0.0211 (2) | |
H9A | 0.2528 | 0.7404 | 0.4663 | 0.025* | |
H9B | 0.2336 | 0.7254 | 0.5764 | 0.025* | |
C10 | 0.05623 (14) | 0.65495 (11) | 0.42841 (12) | 0.0297 (3) | |
H10A | −0.0054 | 0.7237 | 0.4075 | 0.045* | |
H10B | 0.0255 | 0.6022 | 0.4689 | 0.045* | |
H10C | 0.0442 | 0.6182 | 0.3592 | 0.045* | |
C11 | 0.70375 (12) | 0.47143 (10) | 0.70367 (9) | 0.0172 (2) | |
C12 | 0.80061 (13) | 0.57743 (11) | 0.72907 (11) | 0.0232 (2) | |
H12A | 0.9049 | 0.5546 | 0.7633 | 0.035* | |
H12B | 0.7885 | 0.6267 | 0.7823 | 0.035* | |
H12C | 0.7706 | 0.6189 | 0.6579 | 0.035* | |
C13 | 0.68844 (14) | −0.03669 (10) | 0.71190 (10) | 0.0215 (2) | |
H13A | 0.7964 | −0.0261 | 0.7543 | 0.032* | |
H13B | 0.6599 | −0.0782 | 0.6410 | 0.032* | |
H13C | 0.6581 | −0.0803 | 0.7586 | 0.032* | |
H1N1 | 0.5992 (19) | 0.2707 (14) | 0.6701 (14) | 0.037 (4)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0175 (4) | 0.0120 (4) | 0.0265 (4) | 0.0022 (3) | 0.0067 (3) | −0.0010 (3) |
O2 | 0.0152 (4) | 0.0145 (4) | 0.0242 (4) | 0.0039 (3) | 0.0056 (3) | 0.0015 (3) |
O3 | 0.0179 (4) | 0.0180 (4) | 0.0241 (4) | 0.0013 (3) | 0.0069 (3) | 0.0013 (3) |
O4 | 0.0229 (4) | 0.0128 (4) | 0.0280 (4) | −0.0026 (3) | 0.0095 (4) | −0.0013 (3) |
N1 | 0.0153 (4) | 0.0113 (4) | 0.0177 (4) | 0.0009 (4) | 0.0068 (4) | 0.0009 (3) |
N2 | 0.0182 (4) | 0.0114 (4) | 0.0149 (4) | 0.0006 (3) | 0.0084 (4) | 0.0001 (3) |
C1 | 0.0168 (5) | 0.0132 (5) | 0.0191 (5) | 0.0030 (4) | 0.0088 (4) | 0.0021 (4) |
C2 | 0.0160 (5) | 0.0173 (5) | 0.0224 (5) | −0.0001 (4) | 0.0092 (4) | −0.0001 (4) |
C3 | 0.0202 (5) | 0.0144 (5) | 0.0233 (5) | −0.0034 (4) | 0.0108 (5) | −0.0019 (4) |
C4 | 0.0224 (6) | 0.0116 (5) | 0.0208 (5) | 0.0010 (4) | 0.0111 (4) | 0.0006 (4) |
C5 | 0.0163 (5) | 0.0139 (5) | 0.0158 (5) | 0.0021 (4) | 0.0077 (4) | 0.0006 (4) |
C6 | 0.0173 (5) | 0.0122 (5) | 0.0163 (5) | −0.0005 (4) | 0.0092 (4) | −0.0002 (4) |
C7 | 0.0168 (5) | 0.0133 (5) | 0.0150 (5) | −0.0002 (4) | 0.0071 (4) | 0.0002 (4) |
C8 | 0.0182 (5) | 0.0140 (5) | 0.0158 (5) | −0.0001 (4) | 0.0085 (4) | 0.0001 (4) |
C9 | 0.0210 (6) | 0.0122 (5) | 0.0272 (6) | 0.0038 (4) | 0.0100 (5) | −0.0004 (4) |
C10 | 0.0205 (6) | 0.0212 (6) | 0.0420 (7) | 0.0040 (5) | 0.0116 (6) | 0.0000 (5) |
C11 | 0.0170 (5) | 0.0177 (5) | 0.0152 (5) | −0.0010 (4) | 0.0067 (4) | −0.0007 (4) |
C12 | 0.0184 (5) | 0.0204 (6) | 0.0264 (6) | −0.0038 (5) | 0.0078 (5) | 0.0001 (5) |
C13 | 0.0215 (6) | 0.0192 (6) | 0.0243 (6) | 0.0081 (5) | 0.0119 (5) | 0.0052 (4) |
O1—C8 | 1.3430 (14) | C4—H4A | 0.9300 |
O1—C9 | 1.4510 (13) | C5—C6 | 1.4041 (15) |
O2—C5 | 1.3660 (13) | C7—C11 | 1.4732 (16) |
O2—C13 | 1.4355 (13) | C7—C8 | 1.4852 (15) |
O3—C11 | 1.2393 (13) | C9—C10 | 1.5053 (17) |
O4—C8 | 1.2143 (13) | C9—H9A | 0.9700 |
N1—N2 | 1.3064 (12) | C9—H9B | 0.9700 |
N1—C6 | 1.4019 (14) | C10—H10A | 0.9600 |
N1—H1N1 | 0.898 (17) | C10—H10B | 0.9600 |
N2—C7 | 1.3201 (14) | C10—H10C | 0.9600 |
C1—C2 | 1.3885 (15) | C11—C12 | 1.4967 (16) |
C1—C6 | 1.3896 (15) | C12—H12A | 0.9600 |
C1—H1A | 0.9300 | C12—H12B | 0.9600 |
C2—C3 | 1.3880 (16) | C12—H12C | 0.9600 |
C2—H2A | 0.9300 | C13—H13A | 0.9600 |
C3—C4 | 1.3925 (16) | C13—H13B | 0.9600 |
C3—H3A | 0.9300 | C13—H13C | 0.9600 |
C4—C5 | 1.3891 (15) | ||
C8—O1—C9 | 115.03 (9) | O1—C8—C7 | 112.17 (9) |
C5—O2—C13 | 117.52 (9) | O1—C9—C10 | 106.76 (9) |
N2—N1—C6 | 119.32 (9) | O1—C9—H9A | 110.4 |
N2—N1—H1N1 | 120.1 (11) | C10—C9—H9A | 110.4 |
C6—N1—H1N1 | 120.6 (11) | O1—C9—H9B | 110.4 |
N1—N2—C7 | 121.15 (9) | C10—C9—H9B | 110.4 |
C2—C1—C6 | 119.85 (10) | H9A—C9—H9B | 108.6 |
C2—C1—H1A | 120.1 | C9—C10—H10A | 109.5 |
C6—C1—H1A | 120.1 | C9—C10—H10B | 109.5 |
C3—C2—C1 | 119.66 (10) | H10A—C10—H10B | 109.5 |
C3—C2—H2A | 120.2 | C9—C10—H10C | 109.5 |
C1—C2—H2A | 120.2 | H10A—C10—H10C | 109.5 |
C2—C3—C4 | 121.15 (10) | H10B—C10—H10C | 109.5 |
C2—C3—H3A | 119.4 | O3—C11—C7 | 119.26 (10) |
C4—C3—H3A | 119.4 | O3—C11—C12 | 119.68 (10) |
C5—C4—C3 | 119.23 (10) | C7—C11—C12 | 121.05 (10) |
C5—C4—H4A | 120.4 | C11—C12—H12A | 109.5 |
C3—C4—H4A | 120.4 | C11—C12—H12B | 109.5 |
O2—C5—C4 | 125.60 (10) | H12A—C12—H12B | 109.5 |
O2—C5—C6 | 114.58 (9) | C11—C12—H12C | 109.5 |
C4—C5—C6 | 119.81 (10) | H12A—C12—H12C | 109.5 |
C1—C6—N1 | 122.73 (10) | H12B—C12—H12C | 109.5 |
C1—C6—C5 | 120.29 (10) | O2—C13—H13A | 109.5 |
N1—C6—C5 | 116.98 (9) | O2—C13—H13B | 109.5 |
N2—C7—C11 | 124.05 (10) | H13A—C13—H13B | 109.5 |
N2—C7—C8 | 113.80 (9) | O2—C13—H13C | 109.5 |
C11—C7—C8 | 122.15 (10) | H13A—C13—H13C | 109.5 |
O4—C8—O1 | 122.70 (10) | H13B—C13—H13C | 109.5 |
O4—C8—C7 | 125.13 (10) | ||
C6—N1—N2—C7 | −178.24 (9) | C4—C5—C6—N1 | 179.90 (10) |
C6—C1—C2—C3 | 0.46 (16) | N1—N2—C7—C11 | 2.76 (16) |
C1—C2—C3—C4 | −0.43 (17) | N1—N2—C7—C8 | −177.39 (9) |
C2—C3—C4—C5 | 0.18 (17) | C9—O1—C8—O4 | −3.10 (15) |
C13—O2—C5—C4 | 5.71 (15) | C9—O1—C8—C7 | 176.32 (9) |
C13—O2—C5—C6 | −174.96 (9) | N2—C7—C8—O4 | 174.02 (10) |
C3—C4—C5—O2 | 179.33 (10) | C11—C7—C8—O4 | −6.12 (17) |
C3—C4—C5—C6 | 0.03 (16) | N2—C7—C8—O1 | −5.37 (13) |
C2—C1—C6—N1 | 179.86 (10) | C11—C7—C8—O1 | 174.48 (9) |
C2—C1—C6—C5 | −0.26 (15) | C8—O1—C9—C10 | 179.35 (10) |
N2—N1—C6—C1 | 0.42 (15) | N2—C7—C11—O3 | −6.31 (16) |
N2—N1—C6—C5 | −179.46 (9) | C8—C7—C11—O3 | 173.85 (10) |
O2—C5—C6—C1 | −179.36 (9) | N2—C7—C11—C12 | 172.36 (10) |
C4—C5—C6—C1 | 0.01 (15) | C8—C7—C11—C12 | −7.48 (15) |
O2—C5—C6—N1 | 0.53 (13) |
Cg1 is the centroid of the C1–C6 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N1···O3 | 0.90 (2) | 1.886 (19) | 2.5715 (15) | 131.6 (14) |
C13—H13C···N2i | 0.96 | 2.58 | 3.4835 (18) | 156 |
C12—H12B···Cg1ii | 0.96 | 2.92 | 3.6620 (15) | 135 |
C13—H13B···Cg1iii | 0.96 | 2.66 | 3.4887 (14) | 145 |
Symmetry codes: (i) −x+1, y−1/2, −z+3/2; (ii) −x+1, y+1/2, −z+3/2; (iii) −x+1, −y, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C13H16N2O4 |
Mr | 264.28 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 100 |
a, b, c (Å) | 10.1885 (4), 11.4967 (4), 13.2492 (5) |
β (°) | 120.003 (3) |
V (Å3) | 1343.97 (9) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.75 × 0.27 × 0.20 |
Data collection | |
Diffractometer | Bruker SMART APEXII CCD area-detector |
Absorption correction | Multi-scan (SADABS; Bruker, 2009) |
Tmin, Tmax | 0.931, 0.981 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 14963, 3909, 3123 |
Rint | 0.028 |
(sin θ/λ)max (Å−1) | 0.703 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.044, 0.116, 1.03 |
No. of reflections | 3909 |
No. of parameters | 179 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.35, −0.30 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008), SHELXTL (Sheldrick, 2008 and PLATON (Spek, 2009).
Cg1 is the centroid of the C1–C6 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N1···O3 | 0.90 (2) | 1.886 (19) | 2.5715 (15) | 131.6 (14) |
C13—H13C···N2i | 0.96 | 2.5800 | 3.4835 (18) | 156 |
C12—H12B···Cg1ii | 0.96 | 2.92 | 3.6620 (15) | 135 |
C13—H13B···Cg1iii | 0.96 | 2.66 | 3.4887 (14) | 145 |
Symmetry codes: (i) −x+1, y−1/2, −z+3/2; (ii) −x+1, y+1/2, −z+3/2; (iii) −x+1, −y, −z+1. |
Footnotes
‡Thomson Reuters ResearcherID: A-3561-2009.
Acknowledgements
HKF and MH thank the Malaysian Government and Universiti Sains Malaysia for the Research University grant No. 1001/PFIZIK/811160. MH also thanks Universiti Sains Malaysia for a post-doctoral research fellowship.
References
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Pyrazole derivatives are well established in the literature as important biologically effective heterocyclic compounds (Rai et al., 2008). These derivatives are the subject of many research studies due to their widespread potential pharmacological activities such as antiinflammatory (Girisha et al., 2010), antipyretic, antimicrobial (Isloor et al., 2009) and antiviral activities. The widely prescribed anti-inflammatory pyrazole derivatives, celecoxib and deracoxib, are selective COX-2 inhibitors with reduced ulcerogenic side effects. The title compound, ethyl-2-[(2-methoxyphenyl) hydrazinylidene]-3-oxobutanoate is a key intermediate in the preparation of pyrazole derivative which in turn was obtained by the condensation of 2-[(2-substituted phenyl)hydrazinylidene]-3-oxobutanoate with thiosemicarbazide in glacial acetic acid medium.
Fig. 1 shows the molecular structure of the title compound (I). The molecule adopts an E-configuration with respect to the central C6═N1 double bond. An intramolecular N1—H1N1···O3 interaction generates an S(6) ring (Bernstein et al., 1995). In the crystal, (Fig. 2), adjacent molecules are interconnected into one-dimensional chains along [010] via intermolecular C13—H13C···N2i hydrogen bonds. Furthermore, the crystal structure is stabilized by C—H···π interactions (Table 1) involving the C1–C6 (centroid Cg1) ring.