2-Amino-6-(quinoline-2-carboxamido)­pyridinium nitrate

Van der Berg, P.C.W.; Visser, H.G.; Roodt, A.

doi:10.1107/S1600536812036562

organic compounds

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ISSN: 2056-9890

Volume 68| Part 9| September 2012| Page o2808

doi:10.1107/S1600536812036562

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2-Amino-6-(quinoline-2-carboxamido)pyridinium nitrate

Phillipus C. W. Van der Berg,^a ^* Hendrik G. Visser ^a and Andreas Roodt ^a

^aDepartment of Chemistry, University of the Free State, PO Box 339, Bloemfontein 9300, South Africa
^*Correspondence e-mail: vanderbergpcw@ufs.ac.za

(Received 31 July 2012; accepted 22 August 2012; online 31 August 2012)

In the title salt, C₁₅H₁₃N₄O⁺·NO₃⁻, an extensive network of N—H⋯N, N—H⋯O and C—H⋯O hydrogen-bond interactions are observed throughout the structure. Further stabilization is obtained by π–π stacking interactions between inversion-related quinoline systems and inversion-related pyridine rings, with respective centroid–centroid distances of 3.5866 (6) and 3.3980 (6) Å.

Related literature

For related radiopharmaceutical structures, see: Al-Dajani et al. (2010 ); Jain et al. (2004 ); Van der Berg et al. (2011 ).

Experimental

Crystal data

C₁₅H₁₃N₄O⁺·NO₃⁻
M_r = 327.30
Monoclinic, P 2₁ /c
a = 8.183 (2) Å
b = 11.768 (3) Å
c = 14.979 (4) Å
β = 98.37 (1)°
V = 1427.1 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 100 K
0.49 × 0.41 × 0.31 mm

Data collection

Bruker X8 APEXII KappaCCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2008 ) T_min = 0.990, T_max = 0.994
26710 measured reflections
3555 independent reflections
3180 reflections with I > 2σ(I)
R_int = 0.023

Refinement

R[F² > 2σ(F²)] = 0.035
wR(F²) = 0.1
S = 1.04
3555 reflections
233 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.42 e Å⁻³
Δρ_min = −0.25 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O3	0.892 (18)	2.019 (19)	2.8721 (14)	159.7 (16)
N1—H1B⋯O4ⁱ	0.836 (19)	2.204 (19)	3.0202 (14)	165.1 (16)
N2—H2A⋯O1	0.848 (19)	1.984 (18)	2.6458 (12)	134.1 (16)
N2—H2A⋯O3	0.848 (19)	2.496 (18)	3.2058 (12)	141.7 (15)
N3—H3A⋯O3ⁱⁱ	0.857 (17)	2.153 (17)	2.9652 (12)	158.2 (15)
N3—H3A⋯N4	0.857 (17)	2.288 (16)	2.6879 (15)	108.7 (13)
C4—H4⋯O3ⁱⁱ	0.93	2.44	3.1947 (14)	138
C11—H11⋯O4ⁱⁱⁱ	0.93	2.53	3.3460 (14)	147
C12—H12⋯O2^iv	0.93	2.5	3.2901 (14)	142
C14—H14⋯O2ⁱⁱ	0.93	2.55	3.1840 (14)	126
Symmetry codes: (i) $[-x+1, y+{\script{1\over 2}}, -z+{\script{5\over 2}}]$ ; (ii) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (iii) $[-x+2, y-{\script{1\over 2}}, -z+{\script{5\over 2}}]$ ; (iv) -x+2, -y, -z+2.

Data collection: APEX2 (Bruker, 2011 ); cell refinement: SAINT-Plus (Bruker, 2008); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2005 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812036562/pk2439sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812036562/pk2439Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812036562/pk2439Isup3.cml

checkCIF report

Comment top

The title compound was synthesized as a ligand for potential use in medical and radiopharmaceutical applications. The asymmetric unit in the title compound contains a C₁₅H₁₃N₄O cation and a NO₃^- counter ion. A range of N—H···N, N—H···O and C—H···O hydrogen interactions are observed throughout the structure. Further stabilization of the crystal structure is obtained by π-π stacking interactions between inversion-related quinolines and inversion-related pyridines with respective centroid-to-centroid distances of 3.5866 (6) Å and 3.3980 (6) Å (see Fig. 2). For similar structures that form part of our radiopharmaceutical research see: Al-Dajani et al. (2010); Jain et al. (2004) and Van der Berg et al. (2011).

Related literature top

For related radiopharmaceutical structures, see: Al-Dajani et al. (2010); Jain et al. (2004); Van der Berg et al. (2011).

Experimental top

Under oxygen atmosphere: Quinaldic acid (0.8013 g, 4.627 mmol) was added as a solid in one portion to a suspension of 2,6-diaminopyridine (0.5000 g, 4.582 mmol) in pyridine (10 ml) and the mixture was stirred at 40 °C for 40 min. Triphenylphosphite (10 ml) was added dropwise over 10 minutes, after which the temperature was increased to 90–100 °C and stirred for a further 24 h. On cooling the precipitate was filtered, washed with H₂O (50 ml) and then MeOH (50 ml). The product was dissolved in diluted HNO₃ and left to stand at room temperature. Yellow crystals were obtained after five days.

Computing details top

Data collection: APEX2 (Bruker, 2011); cell refinement: SAINT-Plus (Bruker, 2008); data reduction: SAINT-Plus (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

Fig. 1. Representation of the title compound, showing displacement ellipsoids (50% probability).

Fig. 2. Packing and illustration of π-π stacking in the crystal.

2-Amino-6-(quinoline-2-carboxamido)pyridinium nitrate top

Crystal data top

C₁₅H₁₃N₄O⁺·NO₃⁻	F(000) = 680
M_r = 327.30	D_x = 1.523 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 9936 reflections
a = 8.183 (2) Å	θ = 2.2–28.3°
b = 11.768 (3) Å	µ = 0.12 mm⁻¹
c = 14.979 (4) Å	T = 100 K
β = 98.37 (1)°	Cuboid, yellow
V = 1427.1 (6) Å³	0.49 × 0.41 × 0.31 mm
Z = 4

Data collection top

Bruker X8 APEXII KappaCCD diffractometer	3555 independent reflections
Radiation source: sealed tube	3180 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.023
ϕ and ω scans	θ_max = 28.4°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −10→10
T_min = 0.990, T_max = 0.994	k = −15→15
26710 measured reflections	l = −19→19

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)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.1	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ²(F_o²) + (0.0537P)² + 0.6672P] where P = (F_o² + 2F_c²)/3
3555 reflections	(Δ/σ)_max = 0.001
233 parameters	Δρ_max = 0.42 e Å⁻³
0 restraints	Δρ_min = −0.25 e Å⁻³

Crystal data top

C₁₅H₁₃N₄O⁺·NO₃⁻	V = 1427.1 (6) Å³
M_r = 327.30	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 8.183 (2) Å	µ = 0.12 mm⁻¹
b = 11.768 (3) Å	T = 100 K
c = 14.979 (4) Å	0.49 × 0.41 × 0.31 mm
β = 98.37 (1)°

Data collection top

Bruker X8 APEXII KappaCCD diffractometer	3555 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2008)	3180 reflections with I > 2σ(I)
T_min = 0.990, T_max = 0.994	R_int = 0.023
26710 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.035	0 restraints
wR(F²) = 0.1	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.42 e Å⁻³
3555 reflections	Δρ_min = −0.25 e Å⁻³
233 parameters

Special details top

Experimental. The intensity data were collected on a Bruker X8 ApexII 4 K Kappa CCD diffractometer using an exposure time of 30 s/frame. A total of 1759 frames were collected with a frame width of 0.5° covering up to θ = 28.28° with 100.00% completeness accomplished.

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
C5	0.44014 (13)	0.29849 (9)	1.00107 (7)	0.0136 (2)
C4	0.36313 (14)	0.35271 (9)	0.92503 (7)	0.0165 (2)
H4	0.3674	0.323	0.8679	0.02*
C3	0.27835 (14)	0.45365 (10)	0.93606 (8)	0.0190 (2)
H3	0.2243	0.4909	0.8854	0.023*
C2	0.27319 (14)	0.49912 (10)	1.02018 (8)	0.0191 (2)
H2	0.2165	0.5665	1.0263	0.023*
C1	0.35435 (13)	0.44278 (9)	1.09694 (8)	0.0161 (2)
C6	0.61016 (12)	0.13855 (9)	1.06647 (7)	0.0130 (2)
C7	0.70961 (12)	0.03990 (9)	1.04078 (7)	0.0128 (2)
C8	0.80954 (13)	−0.01866 (9)	1.11085 (7)	0.0148 (2)
H8	0.812	0.0028	1.1708	0.018*
C9	0.90254 (13)	−0.10779 (9)	1.08810 (7)	0.0156 (2)
H9	0.9709	−0.1475	1.1325	0.019*
C10	0.89350 (13)	−0.13878 (9)	0.99620 (7)	0.0143 (2)
C11	0.98613 (14)	−0.23014 (10)	0.96740 (8)	0.0182 (2)
H11	1.0548	−0.2727	1.0098	0.022*
C12	0.97515 (14)	−0.25610 (10)	0.87763 (8)	0.0208 (2)
H12	1.0371	−0.3157	0.8593	0.025*
C13	0.86987 (14)	−0.19264 (10)	0.81263 (8)	0.0196 (2)
H13	0.8633	−0.2111	0.7518	0.024*
C14	0.77756 (14)	−0.10438 (9)	0.83805 (7)	0.0165 (2)
H14	0.7078	−0.064	0.7947	0.02*
C15	0.78850 (13)	−0.07462 (9)	0.93054 (7)	0.0133 (2)
N1	0.36061 (13)	0.48153 (9)	1.18100 (7)	0.0199 (2)
N2	0.43161 (11)	0.34266 (8)	1.08430 (6)	0.01391 (19)
N3	0.53164 (11)	0.20051 (8)	0.99536 (6)	0.01377 (19)
N4	0.69803 (11)	0.01543 (7)	0.95409 (6)	0.01317 (18)
N5	0.68666 (12)	0.29972 (8)	1.29263 (6)	0.01620 (19)
O1	0.60217 (10)	0.16082 (7)	1.14574 (5)	0.01639 (17)
O2	0.75498 (11)	0.36208 (7)	1.24246 (6)	0.0224 (2)
O3	0.53418 (10)	0.31398 (7)	1.29794 (5)	0.01974 (18)
O4	0.76463 (11)	0.22297 (7)	1.33845 (6)	0.0228 (2)
H1B	0.326 (2)	0.5477 (16)	1.1861 (12)	0.033 (4)*
H1A	0.423 (2)	0.4444 (15)	1.2254 (12)	0.031 (4)*
H2A	0.481 (2)	0.3072 (15)	1.1296 (12)	0.032 (4)*
H3A	0.5452 (19)	0.1790 (14)	0.9423 (11)	0.026 (4)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C5	0.0144 (4)	0.0117 (5)	0.0151 (5)	−0.0008 (4)	0.0036 (4)	−0.0006 (4)
C4	0.0196 (5)	0.0159 (5)	0.0139 (5)	0.0001 (4)	0.0027 (4)	0.0000 (4)
C3	0.0215 (5)	0.0168 (5)	0.0182 (5)	0.0031 (4)	0.0017 (4)	0.0045 (4)
C2	0.0230 (5)	0.0134 (5)	0.0212 (6)	0.0051 (4)	0.0045 (4)	0.0017 (4)
C1	0.0182 (5)	0.0131 (5)	0.0178 (5)	0.0006 (4)	0.0060 (4)	−0.0002 (4)
C6	0.0127 (4)	0.0112 (5)	0.0152 (5)	−0.0015 (4)	0.0018 (4)	−0.0011 (4)
C7	0.0125 (5)	0.0111 (4)	0.0151 (5)	−0.0010 (3)	0.0027 (4)	−0.0007 (4)
C8	0.0152 (5)	0.0165 (5)	0.0129 (5)	−0.0006 (4)	0.0025 (4)	−0.0002 (4)
C9	0.0141 (5)	0.0165 (5)	0.0158 (5)	0.0010 (4)	0.0006 (4)	0.0031 (4)
C10	0.0125 (5)	0.0130 (5)	0.0177 (5)	−0.0005 (4)	0.0034 (4)	0.0004 (4)
C11	0.0164 (5)	0.0160 (5)	0.0219 (6)	0.0037 (4)	0.0018 (4)	0.0007 (4)
C12	0.0198 (5)	0.0165 (5)	0.0268 (6)	0.0041 (4)	0.0062 (4)	−0.0045 (4)
C13	0.0223 (5)	0.0198 (5)	0.0173 (5)	0.0010 (4)	0.0049 (4)	−0.0043 (4)
C14	0.0191 (5)	0.0153 (5)	0.0150 (5)	0.0006 (4)	0.0018 (4)	−0.0003 (4)
C15	0.0130 (4)	0.0115 (5)	0.0156 (5)	−0.0008 (3)	0.0035 (4)	−0.0001 (4)
N1	0.0288 (5)	0.0151 (5)	0.0166 (5)	0.0058 (4)	0.0059 (4)	−0.0011 (4)
N2	0.0171 (4)	0.0119 (4)	0.0129 (4)	0.0021 (3)	0.0027 (3)	0.0005 (3)
N3	0.0175 (4)	0.0120 (4)	0.0122 (4)	0.0018 (3)	0.0033 (3)	−0.0009 (3)
N4	0.0142 (4)	0.0111 (4)	0.0144 (4)	−0.0003 (3)	0.0026 (3)	−0.0008 (3)
N5	0.0221 (5)	0.0142 (4)	0.0121 (4)	−0.0034 (3)	0.0016 (3)	−0.0018 (3)
O1	0.0202 (4)	0.0155 (4)	0.0133 (4)	0.0019 (3)	0.0020 (3)	−0.0023 (3)
O2	0.0317 (5)	0.0184 (4)	0.0195 (4)	−0.0055 (3)	0.0111 (3)	0.0005 (3)
O3	0.0196 (4)	0.0234 (4)	0.0163 (4)	−0.0020 (3)	0.0031 (3)	−0.0002 (3)
O4	0.0269 (4)	0.0182 (4)	0.0206 (4)	−0.0006 (3)	−0.0052 (3)	0.0025 (3)

Geometric parameters (Å, º) top

C5—N2	1.3618 (14)	C9—H9	0.93
C5—C4	1.3758 (15)	C10—C11	1.4183 (15)
C5—N3	1.3842 (13)	C10—C15	1.4246 (15)
C4—C3	1.3974 (15)	C11—C12	1.3690 (17)
C4—H4	0.93	C11—H11	0.93
C3—C2	1.3753 (16)	C12—C13	1.4156 (17)
C3—H3	0.93	C12—H12	0.93
C2—C1	1.4073 (16)	C13—C14	1.3704 (15)
C2—H2	0.93	C13—H13	0.93
C1—N1	1.3332 (15)	C14—C15	1.4191 (15)
C1—N2	1.3633 (14)	C14—H14	0.93
C6—O1	1.2270 (13)	C15—N4	1.3680 (13)
C6—N3	1.3711 (14)	N1—H1B	0.836 (19)
C6—C7	1.4997 (14)	N1—H1A	0.892 (18)
C7—N4	1.3200 (13)	N2—H2A	0.848 (19)
C7—C8	1.4125 (14)	N3—H3A	0.857 (17)
C8—C9	1.3679 (15)	N5—O2	1.2402 (12)
C8—H8	0.93	N5—O4	1.2516 (13)
C9—C10	1.4155 (15)	N5—O3	1.2729 (13)

N2—C5—C4	120.18 (10)	C11—C10—C15	119.15 (10)
N2—C5—N3	118.34 (9)	C12—C11—C10	120.42 (10)
C4—C5—N3	121.46 (10)	C12—C11—H11	119.8
C5—C4—C3	118.15 (10)	C10—C11—H11	119.8
C5—C4—H4	120.9	C11—C12—C13	120.28 (10)
C3—C4—H4	120.9	C11—C12—H12	119.9
C2—C3—C4	121.40 (10)	C13—C12—H12	119.9
C2—C3—H3	119.3	C14—C13—C12	120.90 (10)
C4—C3—H3	119.3	C14—C13—H13	119.5
C3—C2—C1	119.44 (10)	C12—C13—H13	119.5
C3—C2—H2	120.3	C13—C14—C15	119.95 (10)
C1—C2—H2	120.3	C13—C14—H14	120
N1—C1—N2	118.16 (10)	C15—C14—H14	120
N1—C1—C2	124.00 (10)	N4—C15—C14	118.90 (10)
N2—C1—C2	117.84 (10)	N4—C15—C10	121.82 (10)
O1—C6—N3	123.59 (10)	C14—C15—C10	119.28 (10)
O1—C6—C7	121.40 (9)	C1—N1—H1B	116.0 (12)
N3—C6—C7	115.01 (9)	C1—N1—H1A	118.4 (11)
N4—C7—C8	125.13 (10)	H1B—N1—H1A	123.6 (16)
N4—C7—C6	117.22 (9)	C5—N2—C1	122.93 (10)
C8—C7—C6	117.65 (9)	C5—N2—H2A	117.6 (12)
C9—C8—C7	118.16 (10)	C1—N2—H2A	119.4 (12)
C9—C8—H8	120.9	C6—N3—C5	126.27 (9)
C7—C8—H8	120.9	C6—N3—H3A	117.0 (11)
C8—C9—C10	119.18 (10)	C5—N3—H3A	116.6 (11)
C8—C9—H9	120.4	C7—N4—C15	117.29 (9)
C10—C9—H9	120.4	O2—N5—O4	121.37 (10)
C9—C10—C11	122.44 (10)	O2—N5—O3	119.49 (9)
C9—C10—C15	118.40 (9)	O4—N5—O3	119.14 (9)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O3	0.892 (18)	2.019 (19)	2.8721 (14)	159.7 (16)
N1—H1B···O4ⁱ	0.836 (19)	2.204 (19)	3.0202 (14)	165.1 (16)
N2—H2A···O1	0.848 (19)	1.984 (18)	2.6458 (12)	134.1 (16)
N2—H2A···O3	0.848 (19)	2.496 (18)	3.2058 (12)	141.7 (15)
N3—H3A···O3ⁱⁱ	0.857 (17)	2.153 (17)	2.9652 (12)	158.2 (15)
N3—H3A···N4	0.857 (17)	2.288 (16)	2.6879 (15)	108.7 (13)
C4—H4···O3ⁱⁱ	0.93	2.44	3.1947 (14)	138
C11—H11···O4ⁱⁱⁱ	0.93	2.53	3.3460 (14)	147
C12—H12···O2^iv	0.93	2.5	3.2901 (14)	142
C14—H14···O2ⁱⁱ	0.93	2.55	3.1840 (14)	126

Symmetry codes: (i) −x+1, y+1/2, −z+5/2; (ii) x, −y+1/2, z−1/2; (iii) −x+2, y−1/2, −z+5/2; (iv) −x+2, −y, −z+2.

Experimental details

Crystal data
Chemical formula	C₁₅H₁₃N₄O⁺·NO₃⁻
M_r	327.30
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	100
a, b, c (Å)	8.183 (2), 11.768 (3), 14.979 (4)
β (°)	98.37 (1)
V (Å³)	1427.1 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.12
Crystal size (mm)	0.49 × 0.41 × 0.31

Data collection
Diffractometer	Bruker X8 APEXII KappaCCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2008)
T_min, T_max	0.990, 0.994
No. of measured, independent and observed [I > 2σ(I)] reflections	26710, 3555, 3180
R_int	0.023
(sin θ/λ)_max (Å⁻¹)	0.668

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.035, 0.1, 1.03
No. of reflections	3555
No. of parameters	233
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.42, −0.25

Computer programs: APEX2 (Bruker, 2011), SAINT-Plus (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg & Putz, 2005), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O3	0.892 (18)	2.019 (19)	2.8721 (14)	159.7 (16)
N1—H1B···O4ⁱ	0.836 (19)	2.204 (19)	3.0202 (14)	165.1 (16)
N2—H2A···O1	0.848 (19)	1.984 (18)	2.6458 (12)	134.1 (16)
N2—H2A···O3	0.848 (19)	2.496 (18)	3.2058 (12)	141.7 (15)
N3—H3A···O3ⁱⁱ	0.857 (17)	2.153 (17)	2.9652 (12)	158.2 (15)
N3—H3A···N4	0.857 (17)	2.288 (16)	2.6879 (15)	108.7 (13)
C4—H4···O3ⁱⁱ	0.93	2.44	3.1947 (14)	137.8
C11—H11···O4ⁱⁱⁱ	0.93	2.53	3.3460 (14)	147.3
C12—H12···O2^iv	0.93	2.5	3.2901 (14)	142.4
C14—H14···O2ⁱⁱ	0.93	2.55	3.1840 (14)	125.8

Symmetry codes: (i) −x+1, y+1/2, −z+5/2; (ii) x, −y+1/2, z−1/2; (iii) −x+2, y−1/2, −z+5/2; (iv) −x+2, −y, −z+2.

Acknowledgements

The authors would like to thank the Department of Chemistry of the University of the Free State, the NRF, NTeMBI, THRIP and Sasol Ltd for funding.

References

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