5-[Bis­(cyclo­propane­carbonyl)­amino]-4,6-di­chloro­pyrimidine containing a short cyclo­propyl C—H⋯O interaction

Walji, D.V.B.; Storey, J.M.D.; Harrison, W.T.A.

doi:10.1107/S1600536804012577

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 60| Part 6| June 2004| Pages o1110-o1112

https://doi.org/10.1107/S1600536804012577

5-[Bis(cyclopropanecarbonyl)amino]-4,6-dichloropyrimidine containing a short cyclopropyl C—H⋯O interaction

Dhiran V. B. Walji,^a John M. D. Storey ^a and William T. A. Harrison ^a ^*

^aDepartment of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, Scotland
^*Correspondence e-mail: w.harrison@abdn.ac.uk

(Received 20 May 2004; accepted 24 May 2004; online 29 May 2004)

The title compound, C₁₂H₁₁Cl₂N₃O₂, possesses normal intramolecular geometrical parameters. The crystal packing is influenced by C—H⋯O and possible weak π–π stacking interactions.

Comment

A great deal of research has been carried out on pyrimidine systems, fuelled by their important biological applications and properties (Brown, 1994 ). Various dihaloaminopyridines and dihaloaminopyrimidines have proven to be useful in terms of their antiviral activity, particularly for their action towards the Herpes virus (Giovanninetti et al., 1980 ). As part of our general investigations in this area, the title compound, (I), C₁₂H₁₁Cl₂N₃O₂, has been synthesized, albeit in moderate yield. Similarly low yields have also been observed by Giovanninetti et al. (1980) in acylation reactions of dichloroaminopyrimidines.

Compound (I) possesses normal intramolecular geometrical parameters (Table 1). The 4,6-dichloropyrimidine moiety (C1–C4/N1/N2/Cl1/Cl2) is close to being planar; for the non-H atoms, the r.m.s. deviation from the least-squares plane is 0.031 Å. Atom N3 is significantly displaced from the mean plane by 0.204 (3) Å. The dihedral angle between the aromatic ring and the C5/N3/C9 group is 74.81 (10)°. The major conformational difference in the cyclopropanecarbonyl `arms' of (I) concerns the amide carbonyl (C5=O1 and C9=O2) groups. The first of these is close to being eclipsed with respect to the N3—C3 bond, whereas the second is almost anti with respect to the same pair of atoms (Table 1). The cyclopropyl rings [mean C—C = 1.504 (3) Å; mean C—C—C = 60.0 (2)°] are unexceptional.

As well as van der Waals forces, the crystal packing in (I) appears to be influenced by C—H⋯O interactions (Table 2). The first of these bonds involves the atoms C1—H1⋯O1ⁱⁱ (see Table 2 for symmetry code), i.e. the aromatic H atom and an amide carbonyl O-atom acceptor. These bonds help stabilize the [001] stacks of (I) and are generated by c-glide symmetry. The second, with a near-linear C7—H4⋯O2ⁱ bond angle of 173° and a very short H⋯O separation of 2.35 Å, involves a cyclopropyl H atom and the other amide carbonyl O atom as the acceptor species, the acceptor generated by inversion symmetry (Fig. 2), which results in dimers of (I). Allen et al. (1996 ) have shown that C—H⋯O hydrogen bonds from cyclopropyl methylene groups are enhanced because strain inherent in the C3 ring tends to increase the acidity of the CH moieties involved, although the example here appears to be a particularly strong bond.

There may be π–π stacking effects involving the pyrimidine rings (C1–C4/N1/N2, with centroid Cg) in (I). The Cg⋯Cgⁱⁱⁱ [symmetry code: (iii) x, $[3\over 2]$ − y, $[-{1 \over 2}]$ + z; i.e. the c-glide] separation is 3.7160 (12) Å, but the centroids are laterally displaced by the large value of 1.87 Å, suggesting that this is a very weak interaction.

In combination, these effects result (Fig. 3) in stacks of molecules of (I) propagating along [001]. The stacks are crosslinked along [010] by the proposed C7—H4⋯O2ⁱ (Table 2) bonds, whereas along [100] only van der Waals interactions hold the adjacent stacks together. In this direction, the N1⋯Cl2^iv [symmetry code (iv) x − 1, y, z] contact of 3.252 (2) Å is slightly less than the van der Waals radius sum of 3.30 Å for these species (Spek, 2003 ).

Figure 1
View of (I

) (50% displacement ellipsoids). H atoms are drawn as small spheres of arbitrary radii.

Figure 2
Dimerization of molecules of (I

) via the C7—H4⋯O2ⁱ bond (symmetry code as in Table 2

), with 50% probability displacement ellipsoids; all H atoms, except H4, have been omitted for clarity.

Figure 3
The packing in (I

), viewed down [001], with C—H⋯O interactions indicated by dashed lines (50% probability displacement ellipsoids); all H atoms, except H1 and H4, have been omitted for clarity.

Experimental

To prepare (I), 4,6-dichloro-5-aminopyrimidine (0.412 g, 2.512 mmol) was placed in a twin-necked flask and was stirred in dry dichloromethane (35 ml) under a nitrogen atmosphere. The reaction mixture was cooled to 273 K, whereupon Hünig's base (7.54 mmol, 1.30 ml) was added, and the reaction was stirred for approximately 10 min. Cyclopropane carbonyl chloride (7.54 mmol, 0.68 ml) was then added, and the reaction was warmed to room temperature and stirred for 24 h. The progress of the reaction was monitored using thin-layer chromatography (TLC, solvent dichloromethane), showing the product with an R_F of 0.19 The reaction mixture was then washed with saturated brine (3 × 20 ml) and dried with magnesium sulfate, and the solvent was removed at reduced pressure. The resultant organic liquor was purified using flash chromatography (solvent 3:0.1 chloroform/methanol). Overlap of the starting material with the product required the use of a different solvent system (2:2:0.1 dichloromethane/hexane/methanol) to further purify the product (R_F = 0.17). Vapour diffusion crystallization was used to obtain white crystals of (I); dichloromethane was used as the solvent and hexane was used as the precipitant. The yield obtained was 0.063 g (8.4%). M.p. 406–409 K. FT–IR (KBr, cm⁻¹): ν_max 3062 (w, CH, cyclopropane), 1697, 1713 (C=O, carbonyl), 1517, 1413 (s, C=N, conjugated, cyclic, pyrimidine), 1541 (m, C—N, tertiary amine), 1174 (s, pyrimidine-NR₂), 813 (s, pyrimidine-Cl); ¹H (400 MHz; CDCl₃): δ 0.96 (4H, ddd), 1.20 (4H, ddd), 2.01 (2H, tt), 8.76 (1H, s); ¹³C (100 MHz, CDCl₃): δ 11.2, 15.7, 131.4, 157.3, 161.9, 174.1. Elemental analysis data were consistent with the crystallographic results: found: C 47.93, H 3.58, N 13.75, Cl 22.78%; calculated for C₁₂H₁₁Cl₂N₃O₂: C 48.02, H 3.69, N 14.00, Cl 23.62%.

Crystal data

C₁₂H₁₁Cl₂N₃O₂
M_r = 300.14
Monoclinic, P2₁/c
a = 7.6677 (3) Å
b = 26.7366 (12) Å
c = 6.6477 (3) Å
β = 109.065 (2)°
V = 1288.08 (10) Å³
Z = 4
D_x = 1.548 Mg m⁻³
Mo Kα radiation
Cell parameters from 14 708 reflections
θ = 2.9–27.5°
μ = 0.51 mm⁻¹
T = 120 (2) K
Rod, colourless
0.50 × 0.10 × 0.10 mm

Data collection

Nonius KappaCCD diffractometer
ω and φ scans
Absorption correction: multi-scan (SORTAV; Blessing, 1995 ) T_min = 0.787, T_max = 0.951
13 247 measured reflections
2937 independent reflections
1960 reflections with I > 2σ(I)
R_int = 0.077
θ_max = 27.5°
h = −9 → 9
k = −34 → 34
l = −8 → 8

Refinement

Refinement on F²
R[F² > 2σ(F²)] = 0.043
wR(F²) = 0.104
S = 0.98
2937 reflections
172 parameters
H-atom parameters constrained
w = 1/[σ²(F_o²) + (0.0514P)²] where P = (F_o² + 2F_c²)/3
(Δ/σ)_max = 0.001
Δρ_max = 0.30 e Å⁻³
Δρ_min = −0.35 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

C1—N2	1.331 (3)
C1—N1	1.336 (3)
C2—N2	1.330 (3)
C2—C3	1.381 (3)
C2—Cl2	1.725 (2)
C3—C4	1.386 (3)
C3—N3	1.425 (3)
C4—N1	1.322 (3)
C4—Cl1	1.725 (2)

O2—C9—N3—C3	−156.7 (2)
O1—C5—N3—C3	10.6 (3)

Table 2
Hydrogen-bonding geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C7—H4⋯O2ⁱ	0.99	2.35	3.339 (3)	173
C1—H1⋯O1ⁱⁱ	0.95	2.51	3.203 (3)	130
Symmetry codes: (i) 2-x,1-y,-z; (ii) $[x,{\script{3\over 2}}-y,{\script{1\over 2}}+z]$ .

All H atoms were placed in calculated positions (C—H = 0.95–1.00 Å) and refined as riding on their carrier atoms, with U_iso(H) = 1.2U_eq(carrier atom).

Data collection: COLLECT (Nonius, 1998 ); cell refinement: HKL SCALEPACK (Otwinowski & Minor, 1997 ); data reduction: HKL DENZO (Otwinowski & Minor, 1997) and SCALEPACK, and SORTAV (Blessing, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP3 (Farrugia, 1997 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536804012577/hg6054sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536804012577/hg6054Isup2.hkl

Computing details top

Data collection: Collect (Nonius BV, 1998); cell refinement: HKL SCALEPACK (Otwinowski & Minor 1997); data reduction: HKL DENZO (Otwinowski & Minor, 1997) and SCALEPACK, and SORTAV (Blessing 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97.

5-[Bis(cyclopropanecarbonyl)amino]-4,6-dichloropyrimidine top

Crystal data top

C₁₂H₁₁Cl₂N₃O₂	F(000) = 616
M_r = 300.14	D_x = 1.548 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 14708 reflections
a = 7.6677 (3) Å	θ = 2.9–27.5°
b = 26.7366 (12) Å	µ = 0.51 mm⁻¹
c = 6.6477 (3) Å	T = 120 K
β = 109.065 (2)°	Rod, colourless
V = 1288.08 (10) Å³	0.50 × 0.10 × 0.10 mm
Z = 4

Data collection top

Enraf–Nonius KappaCCD diffractometer	2937 independent reflections
Radiation source: fine-focus sealed tube	1960 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.077
ω and φ scans	θ_max = 27.5°, θ_min = 3.1°
Absorption correction: multi-scan (SORTAV; Blessing, 1995)	h = −9→9
T_min = 0.787, T_max = 0.951	k = −34→34
13247 measured reflections	l = −8→8

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.043	H-atom parameters constrained
wR(F²) = 0.104	w = 1/[σ²(F_o²) + (0.0514P)²] where P = (F_o² + 2F_c²)/3
S = 0.98	(Δ/σ)_max = 0.001
2937 reflections	Δρ_max = 0.30 e Å⁻³
172 parameters	Δρ_min = −0.35 e Å⁻³
0 restraints

Special details top

Experimental. Melting points were determined using a Kofler hot-stage apparatus and are uncorrected. Infrared spectra were recorded using a Nicolet Avatar 320 F T–IR spectrometer, using KBr discs. NMR spectra were determined using a Varian Unity Inova spectrometer (400 MHz, ¹H and 100 MHz, ¹³C) using deuterated (2H)-chloroform as solvent, with the presence of residual CHCl₃, as the reference at 7.26 p.p.m., with J values in Hz).

Flash chromatography was carried out using silica gel (230–400 mesh), TLC was performed on plates cut from 20x20 cm aluminium sheets, coated with Merck Kieselgel 60 silica with F254 indicator. Dry dichloromethane was distilled under argon, from calcium hydride prior to use. All glassware was pre-dried in the oven before use and cooled in an argon atmosphere.

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
C1	0.5414 (3)	0.76193 (9)	0.1288 (3)	0.0203 (5)
H1	0.4834	0.7937	0.1158	0.024*
C2	0.7893 (3)	0.71636 (9)	0.1331 (3)	0.0179 (5)
C3	0.6997 (3)	0.67255 (8)	0.1500 (3)	0.0174 (5)
C4	0.5243 (3)	0.67875 (9)	0.1631 (3)	0.0188 (5)
C5	0.6995 (3)	0.59998 (9)	−0.0595 (4)	0.0214 (5)
C6	0.7272 (4)	0.54607 (9)	−0.0764 (4)	0.0304 (6)
H2	0.8099	0.5282	0.0513	0.037*
C7	0.7186 (4)	0.52743 (11)	−0.2948 (5)	0.0357 (7)
H3	0.7035	0.5526	−0.4083	0.043*
H4	0.7968	0.4984	−0.3017	0.043*
C8	0.5606 (4)	0.51833 (11)	−0.2210 (4)	0.0374 (7)
H5	0.5399	0.4837	−0.1816	0.045*
H6	0.4467	0.5379	−0.2883	0.045*
C9	0.9288 (3)	0.60715 (9)	0.3131 (4)	0.0227 (5)
C10	0.9574 (3)	0.63209 (9)	0.5189 (4)	0.0240 (6)
H7	0.8567	0.6543	0.5322	0.029*
C11	1.0718 (3)	0.60382 (11)	0.7154 (4)	0.0303 (6)
H8	1.0402	0.6082	0.8473	0.036*
H9	1.1149	0.5699	0.6949	0.036*
C12	1.1561 (3)	0.64675 (10)	0.6412 (4)	0.0294 (6)
H10	1.2513	0.6395	0.5743	0.035*
H11	1.1766	0.6778	0.7267	0.035*
Cl1	0.40433 (8)	0.62739 (2)	0.20502 (9)	0.02528 (17)
Cl2	1.01125 (7)	0.71437 (2)	0.12343 (9)	0.02406 (17)
O1	0.6038 (2)	0.62476 (6)	−0.2070 (3)	0.0257 (4)
O2	1.0293 (2)	0.57489 (7)	0.2855 (3)	0.0340 (5)
N1	0.4413 (3)	0.72255 (7)	0.1495 (3)	0.0203 (4)
N2	0.7137 (2)	0.76143 (7)	0.1244 (3)	0.0196 (4)
N3	0.7750 (2)	0.62417 (7)	0.1419 (3)	0.0187 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0216 (12)	0.0217 (13)	0.0163 (12)	0.0038 (10)	0.0043 (10)	−0.0021 (9)
C2	0.0177 (11)	0.0222 (13)	0.0122 (11)	0.0003 (10)	0.0027 (9)	−0.0016 (9)
C3	0.0185 (12)	0.0173 (12)	0.0147 (11)	0.0038 (9)	0.0030 (9)	−0.0024 (9)
C4	0.0194 (12)	0.0205 (13)	0.0142 (11)	−0.0002 (10)	0.0021 (9)	−0.0009 (9)
C5	0.0195 (12)	0.0216 (13)	0.0242 (13)	−0.0016 (10)	0.0085 (11)	−0.0016 (10)
C6	0.0339 (14)	0.0179 (14)	0.0322 (14)	0.0018 (11)	0.0008 (12)	−0.0021 (11)
C7	0.0346 (15)	0.0275 (16)	0.0449 (16)	0.0030 (13)	0.0128 (13)	−0.0144 (13)
C8	0.0444 (17)	0.0226 (15)	0.0414 (16)	−0.0055 (12)	0.0088 (14)	−0.0082 (12)
C9	0.0195 (12)	0.0199 (13)	0.0272 (13)	0.0005 (10)	0.0056 (10)	0.0026 (10)
C10	0.0198 (12)	0.0288 (15)	0.0212 (12)	0.0062 (11)	0.0035 (10)	0.0023 (10)
C11	0.0244 (13)	0.0388 (17)	0.0237 (13)	0.0016 (12)	0.0023 (11)	0.0069 (11)
C12	0.0242 (13)	0.0341 (16)	0.0258 (13)	−0.0036 (12)	0.0024 (11)	−0.0019 (11)
Cl1	0.0214 (3)	0.0248 (3)	0.0300 (3)	−0.0029 (2)	0.0089 (2)	0.0013 (3)
Cl2	0.0185 (3)	0.0255 (3)	0.0294 (3)	0.0003 (2)	0.0095 (2)	0.0012 (2)
O1	0.0276 (9)	0.0220 (9)	0.0232 (9)	0.0040 (8)	0.0025 (7)	−0.0026 (7)
O2	0.0275 (10)	0.0310 (11)	0.0375 (10)	0.0120 (8)	0.0022 (8)	−0.0055 (8)
N1	0.0183 (10)	0.0234 (12)	0.0180 (10)	0.0032 (9)	0.0043 (8)	−0.0005 (8)
N2	0.0213 (10)	0.0177 (11)	0.0182 (10)	0.0013 (8)	0.0044 (8)	0.0006 (8)
N3	0.0183 (10)	0.0139 (10)	0.0214 (10)	0.0022 (8)	0.0033 (8)	−0.0013 (8)

Geometric parameters (Å, º) top

C1—N2	1.331 (3)	C7—C8	1.468 (4)
C1—N1	1.336 (3)	C7—H3	0.9900
C1—H1	0.9500	C7—H4	0.9900
C2—N2	1.330 (3)	C8—H5	0.9900
C2—C3	1.381 (3)	C8—H6	0.9900
C2—Cl2	1.725 (2)	C9—O2	1.209 (3)
C3—C4	1.386 (3)	C9—N3	1.420 (3)
C3—N3	1.425 (3)	C9—C10	1.473 (3)
C4—N1	1.322 (3)	C10—C11	1.516 (3)
C4—Cl1	1.725 (2)	C10—C12	1.526 (3)
C5—O1	1.212 (3)	C10—H7	1.0000
C5—N3	1.428 (3)	C11—C12	1.479 (4)
C5—C6	1.467 (3)	C11—H8	0.9900
C6—C7	1.516 (4)	C11—H9	0.9900
C6—C8	1.518 (4)	C12—H10	0.9900
C6—H2	1.0000	C12—H11	0.9900

N2—C1—N1	127.0 (2)	C7—C8—H6	117.7
N2—C1—H1	116.5	C6—C8—H6	117.7
N1—C1—H1	116.5	H5—C8—H6	114.8
N2—C2—C3	123.4 (2)	O2—C9—N3	120.7 (2)
N2—C2—Cl2	116.61 (17)	O2—C9—C10	123.7 (2)
C3—C2—Cl2	119.98 (17)	N3—C9—C10	115.6 (2)
C2—C3—C4	115.0 (2)	C9—C10—C11	116.3 (2)
C2—C3—N3	123.3 (2)	C9—C10—C12	115.5 (2)
C4—C3—N3	121.6 (2)	C11—C10—C12	58.16 (16)
N1—C4—C3	123.8 (2)	C9—C10—H7	117.8
N1—C4—Cl1	116.51 (17)	C11—C10—H7	117.8
C3—C4—Cl1	119.64 (17)	C12—C10—H7	117.8
O1—C5—N3	117.6 (2)	C12—C11—C10	61.25 (16)
O1—C5—C6	122.7 (2)	C12—C11—H8	117.6
N3—C5—C6	119.5 (2)	C10—C11—H8	117.6
C5—C6—C7	115.7 (2)	C12—C11—H9	117.6
C5—C6—C8	114.5 (2)	C10—C11—H9	117.6
C7—C6—C8	57.87 (17)	H8—C11—H9	114.7
C5—C6—H2	118.2	C11—C12—C10	60.59 (16)
C7—C6—H2	118.2	C11—C12—H10	117.7
C8—C6—H2	118.2	C10—C12—H10	117.7
C8—C7—C6	61.13 (18)	C11—C12—H11	117.7
C8—C7—H3	117.7	C10—C12—H11	117.7
C6—C7—H3	117.7	H10—C12—H11	114.8
C8—C7—H4	117.7	C4—N1—C1	115.17 (19)
C6—C7—H4	117.7	C2—N2—C1	115.5 (2)
H3—C7—H4	114.8	C9—N3—C3	120.09 (18)
C7—C8—C6	60.99 (18)	C9—N3—C5	125.63 (19)
C7—C8—H5	117.7	C3—N3—C5	113.66 (18)
C6—C8—H5	117.7

N2—C2—C3—C4	−1.6 (3)	C9—C10—C12—C11	−106.3 (2)
Cl2—C2—C3—C4	178.07 (15)	C3—C4—N1—C1	−2.2 (3)
N2—C2—C3—N3	174.74 (19)	Cl1—C4—N1—C1	176.46 (16)
Cl2—C2—C3—N3	−5.6 (3)	N2—C1—N1—C4	−1.3 (3)
C2—C3—C4—N1	3.5 (3)	C3—C2—N2—C1	−1.3 (3)
N3—C3—C4—N1	−172.92 (19)	Cl2—C2—N2—C1	178.99 (16)
C2—C3—C4—Cl1	−175.10 (15)	N1—C1—N2—C2	2.9 (3)
N3—C3—C4—Cl1	8.5 (3)	O2—C9—N3—C3	−156.7 (2)
O1—C5—C6—C7	30.2 (3)	C10—C9—N3—C3	22.0 (3)
N3—C5—C6—C7	−155.0 (2)	O2—C9—N3—C5	13.8 (3)
O1—C5—C6—C8	−34.4 (3)	C10—C9—N3—C5	−167.6 (2)
N3—C5—C6—C8	140.4 (2)	C2—C3—N3—C9	70.4 (3)
C5—C6—C7—C8	−104.0 (3)	C4—C3—N3—C9	−113.5 (2)
C5—C6—C8—C7	106.1 (3)	C2—C3—N3—C5	−101.1 (2)
O2—C9—C10—C11	−22.5 (4)	C4—C3—N3—C5	75.0 (2)
N3—C9—C10—C11	158.9 (2)	O1—C5—N3—C9	−160.4 (2)
O2—C9—C10—C12	42.9 (3)	C6—C5—N3—C9	24.5 (3)
N3—C9—C10—C12	−135.7 (2)	O1—C5—N3—C3	10.6 (3)
C9—C10—C11—C12	105.0 (2)	C6—C5—N3—C3	−164.5 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C7—H4···O2ⁱ	0.99	2.35	3.339 (3)	173
C1—H1···O1ⁱⁱ	0.95	2.51	3.203 (3)	130

Symmetry codes: (i) −x+2, −y+1, −z; (ii) x, −y+3/2, z+1/2.

Acknowledgements

We thank the EPSRC UK National Crystallography Service (University of Southampton) for the data collection.

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