N-(2-Methyl­phen­yl)maleamic acid

Gowda, B.T.; Tokarčík, M.; Shakuntala, K.; Kožíšek, J.; Fuess, H.

doi:10.1107/S160053681002012X

organic compounds

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ISSN: 2056-9890

Volume 66| Part 7| July 2010| Page o1554

doi:10.1107/S160053681002012X

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N-(2-Methylphenyl)maleamic acid

B. Thimme Gowda,^a ^* Miroslav Tokarčík,^b K. Shakuntala,^a Jozef Kožíšek ^b and Hartmut Fuess ^c

^aDepartment of Chemistry, Mangalore University, Mangalagangotri 574 199, Mangalore, India, ^bFaculty of Chemical and Food Technology, Slovak Technical University, Radlinského 9, SK-812 37 Bratislava, Slovak Republic, and ^cInstitute of Materials Science, Darmstadt University of Technology, Petersenstrasse 23, D-64287 Darmstadt, Germany
^*Correspondence e-mail: gowdabt@yahoo.com

(Received 18 May 2010; accepted 27 May 2010; online 5 June 2010)

In the title compound, C₁₁H₁₁NO₃, the conformation of the N—H bond is anti to the C=O bond in the amide segment, while it is syn to the ortho-methyl group in the phenyl ring. In the maleamic acid unit, the amide C=O bond is anti to the adjacent C—H bond, while the carboxyl C=O bond is syn to the adjacent C—H bond. The C=O and O—H bonds of the acid group are in the relatively rare anti position to each other. This is an obvious consequence of the intramolecular O—H⋯O hydrogen bond donated to the amide carbonyl group. The ortho-substituted phenyl ring makes a dihedral angle of 12.7 (1)° with the mean plane of the maleamic acid unit. In the crystal structure, intermolecular N—H⋯O hydrogen bonds link the molecules into zigzag chains parallel to [001]. These chains are further linked into sheet by weak π–π interactions [centroid–centroid distance = 3.425 (2) Å].

Related literature

For studies on the effect of ring- and side-chain substitutions on the crystal structures of amides, see: Gowda et al. (2009a ,b ,c ); Prasad et al. (2002 ). For the modes of interlinking carboxylic acids by hydrogen bonds, see: Jagannathan et al. (1994 ); Leiserowitz (1976 ).

Experimental

Crystal data

C₁₁H₁₁NO₃
M_r = 205.21
Monoclinic, P 2₁ /c
a = 7.3942 (3) Å
b = 11.5898 (4) Å
c = 12.9903 (3) Å
β = 114.534 (2)°
V = 1012.72 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 295 K
0.58 × 0.42 × 0.42 mm

Data collection

Oxford Diffraction Gemini R CCD diffractometer
Absorption correction: analytical (CrysAlis PRO; Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]$ ) T_min = 0.922, T_max = 0.962
15644 measured reflections
1776 independent reflections
1453 reflections with I > 2σ(I)
R_int = 0.027

Refinement

R[F² > 2σ(F²)] = 0.034
wR(F²) = 0.098
S = 1.07
1776 reflections
137 parameters
H-atom parameters constrained
Δρ_max = 0.17 e Å⁻³
Δρ_min = −0.13 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1N⋯O3ⁱ	0.86	2.22	3.0665 (14)	167
O2—H2A⋯O1	0.92	1.56	2.4822 (13)	178
Symmetry code: (i) $[x, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: CrysAlis PRO (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]$ ); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ) and DIAMOND (Brandenburg, 2002 ); software used to prepare material for publication: SHELXL97, PLATON (Spek, 2009 ) and WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053681002012X/dn2569sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681002012X/dn2569Isup2.hkl

checkCIF report

Comment top

The amide moiety is an important constituent of many biologically significant compounds. As a part of studying the effect of ring and side chain substitutions on the crystal structures of this class of compounds (Gowda et al., 2009a,b,c; Prasad et al., 2002), the crystal structure of N-(2-methylphenyl)-maleamic acid (I) has been determined (Fig. 1). The conformations of the N—H and the C=O bonds in the amide segment are anti to each other. But the conformation of the N—H bond is syn to the ortho-methyl group in the phenyl ring. In the maleamic acid moiety, the amide C=O bond is anti to the adjacent C—H bond, while the carboxyl C=O bond is syn to the adjacent C—H bond. The observed rare anti conformation of the C=O and O—H bonds of the acid group is similar to that obsrved in N-(2,6-dimethylphenyl)-maleamic acid (Gowda et al., 2009a), N-(3,4-dimethylphenyl)-maleamic acid (Gowda et al., 2009b) and N-(2,4,6-trimethylphenyl)- maleamic acid (Gowda et al., 2009c).

The ortho-substituted phenyl ring makes a dihedral angle of 12.7 (1)° with the mean plane of the maleamic acid moiety (atoms C1, C2, C3, C4, N1, O1, O2 and O3). The orientation of the central amide group –NHOC– with respect to the phenyl ring is partially affected by the intramolecular hydrogen bond C10—H10···O1(amide) and is given by the torsion angle C10—C5—N1—C1 = -17.3 (2)°. Short intramolecular hydrogen bond O—H···O (Table 1) is important characteristic of the maleamic acid moiety. The C2–C3 bond length of 1.330 (2)Å clearly indicates the double bond character. In the crystal structure, the intermolecular N–H···O hydrogen bonds, having the amide N1 atom as donor and carbonyl O3 atom of the carboxyl group as acceptor, link the molecules into zigzag chains running along the [0 0 1] direction. Due to weak π-π interaction between the phenyl and maleamic acid moieties the chains are assembled to form sheets parallel to the bc-plane. One mode of the chain coupling is shown in Fig. 2 as a short contact between the phenyl ring centroid Cg and the C4 atom of the carboxylic group at (-x,-y + 1,-z + 1).

The various modes of interlinking carboxylic acids by hydrogen bonds is described elsewhere (Leiserowitz, 1976). The packing of molecules involving dimeric hydrogen bonded association of each carboxyl group with a centrosymmetrically related neighbor has also been observed (Jagannathan et al., 1994).

Related literature top

For studies on the effect of ring- and side-chain substitutions on the crystal structures of amides, see: Gowda et al. (2009a,b,c); Prasad et al. (2002). For the modes of interlinking carboxylic acids by hydrogen bonds, see: Jagannathan et al. (1994); Leiserowitz (1976).

Experimental top

The solution of maleic anhydride (0.025 mol) in toluene (25 ml) was treated dropwise with the solution of 2-methylaniline (0.025 mol) also in toluene (20 ml) with constant stirring. The resulting mixture was stirred for about 30 min and set aside for an additional 30 min at room temperature for the completion of reaction. The mixture was then treated with dilute hydrochloric acid to remove the unreacted 2-methylaniline. The resultant solid N-(2-methylphenyl)maleamic acid was filtered under suction and washed thoroughly with water to remove the unreacted maleic anhydride and maleic acid. It was recrystallized to constant melting point from ethanol. The purity of the compound was checked by elemental analysis and characterized by its infrared spectra. The single crystals used in X-ray diffraction studies were grown in an ethanol solution by slow evaporation at room temperature.

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2002); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and WinGX (Farrugia, 1999).

Figures top

Fig. 1. Molecular structure of (I) showing the atom labelling scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are represented as small spheres of arbitrary radii.

Fig. 2. Part of the crystal structure of (I) showing the zigzag chains generated by N—H···O hydrogen bonds and extending parallel to the c axis. The chains are weakly coupled by π-π interaction between the phenyl rings and maleamic acid groups. The dashed lines depict the hydrogen bonds, the dotted line depicts the short contact Cg···C4ⁱⁱ. H atoms not involved in hydrogen bonding have been omitted. [Symmetry codes (i): x, -y + 3/2, z - 1/2; (ii) -x,-y + 1,-z + 1].

N-(2-Methylphenyl)maleamic acid top

Crystal data top

C₁₁H₁₁NO₃	F(000) = 432
M_r = 205.21	D_x = 1.346 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 8927 reflections
a = 7.3942 (3) Å	θ = 2.5–29.5°
b = 11.5898 (4) Å	µ = 0.10 mm⁻¹
c = 12.9903 (3) Å	T = 295 K
β = 114.534 (2)°	Prism, colourless
V = 1012.72 (5) Å³	0.58 × 0.42 × 0.42 mm
Z = 4

Data collection top

Oxford Diffraction Gemini R CCD diffractometer	1776 independent reflections
Graphite monochromator	1453 reflections with I > 2σ(I)
Detector resolution: 10.434 pixels mm^-1	R_int = 0.027
ω scans	θ_max = 25°, θ_min = 2.5°
Absorption correction: analytical (CrysAlis PRO; Oxford Diffraction, 2009)	h = −8→8
T_min = 0.922, T_max = 0.962	k = −13→13
15644 measured reflections	l = −15→15

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)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.098	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.056P)² + 0.0996P] where P = (F_o² + 2F_c²)/3
1776 reflections	(Δ/σ)_max < 0.001
137 parameters	Δρ_max = 0.17 e Å⁻³
0 restraints	Δρ_min = −0.13 e Å⁻³

Crystal data top

C₁₁H₁₁NO₃	V = 1012.72 (5) Å³
M_r = 205.21	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 7.3942 (3) Å	µ = 0.10 mm⁻¹
b = 11.5898 (4) Å	T = 295 K
c = 12.9903 (3) Å	0.58 × 0.42 × 0.42 mm
β = 114.534 (2)°

Data collection top

Oxford Diffraction Gemini R CCD diffractometer	1776 independent reflections
Absorption correction: analytical (CrysAlis PRO; Oxford Diffraction, 2009)	1453 reflections with I > 2σ(I)
T_min = 0.922, T_max = 0.962	R_int = 0.027
15644 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.034	0 restraints
wR(F²) = 0.098	H-atom parameters constrained
S = 1.07	Δρ_max = 0.17 e Å⁻³
1776 reflections	Δρ_min = −0.13 e Å⁻³
137 parameters

Special details top

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
O1	0.24625 (18)	0.49123 (8)	0.59119 (8)	0.0661 (3)
O2	0.26421 (19)	0.62958 (9)	0.74100 (8)	0.0701 (4)
H2A	0.2600	0.5770	0.6870	0.105*
O3	0.24623 (18)	0.81655 (10)	0.75227 (8)	0.0711 (4)
N1	0.24594 (15)	0.49437 (9)	0.41733 (8)	0.0432 (3)
H1N	0.2368	0.5389	0.3624	0.052*
C1	0.23624 (18)	0.54568 (11)	0.50723 (9)	0.0416 (3)
C2	0.2115 (2)	0.67235 (11)	0.49860 (10)	0.0444 (3)
H2	0.1931	0.7044	0.4293	0.053*
C3	0.2122 (2)	0.74646 (11)	0.57694 (11)	0.0463 (3)
H3	0.1892	0.8224	0.5517	0.056*
C4	0.2424 (2)	0.73222 (12)	0.69681 (11)	0.0488 (4)
C5	0.26967 (19)	0.37432 (11)	0.40204 (11)	0.0432 (3)
C6	0.2264 (2)	0.33549 (12)	0.29220 (11)	0.0502 (4)
C7	0.2520 (2)	0.21851 (13)	0.27818 (14)	0.0614 (4)
H7	0.2247	0.1910	0.2060	0.074*
C8	0.3162 (3)	0.14215 (13)	0.36698 (15)	0.0680 (5)
H8	0.3303	0.0643	0.3547	0.082*
C9	0.3591 (3)	0.18185 (13)	0.47378 (14)	0.0648 (4)
H9	0.4031	0.1307	0.5345	0.078*
C10	0.3376 (2)	0.29766 (12)	0.49199 (12)	0.0550 (4)
H10	0.3688	0.3242	0.5650	0.066*
C11	0.1553 (3)	0.41495 (15)	0.19286 (12)	0.0711 (5)
H11A	0.1342	0.3721	0.1256	0.107*
H11B	0.2532	0.4737	0.2041	0.107*
H11C	0.0326	0.4502	0.1849	0.107*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.1258 (10)	0.0400 (6)	0.0506 (6)	0.0030 (6)	0.0547 (6)	0.0022 (5)
O2	0.1294 (10)	0.0507 (6)	0.0420 (5)	0.0101 (6)	0.0472 (6)	0.0033 (4)
O3	0.1142 (10)	0.0573 (7)	0.0486 (6)	0.0083 (6)	0.0406 (6)	−0.0134 (5)
N1	0.0616 (7)	0.0386 (6)	0.0353 (5)	−0.0011 (5)	0.0261 (5)	−0.0029 (5)
C1	0.0547 (8)	0.0400 (7)	0.0348 (6)	−0.0020 (6)	0.0233 (6)	−0.0022 (5)
C2	0.0620 (8)	0.0418 (7)	0.0327 (6)	0.0025 (6)	0.0231 (6)	0.0018 (5)
C3	0.0650 (9)	0.0367 (6)	0.0397 (7)	0.0057 (6)	0.0243 (6)	0.0008 (5)
C4	0.0642 (9)	0.0468 (8)	0.0397 (7)	0.0051 (6)	0.0260 (6)	−0.0044 (6)
C5	0.0500 (8)	0.0392 (7)	0.0474 (7)	−0.0045 (5)	0.0272 (6)	−0.0079 (6)
C6	0.0567 (8)	0.0491 (8)	0.0485 (7)	−0.0072 (6)	0.0254 (6)	−0.0151 (6)
C7	0.0701 (10)	0.0541 (9)	0.0626 (9)	−0.0079 (7)	0.0301 (8)	−0.0254 (8)
C8	0.0793 (11)	0.0406 (8)	0.0926 (13)	−0.0042 (7)	0.0441 (10)	−0.0151 (8)
C9	0.0849 (12)	0.0444 (8)	0.0776 (11)	0.0072 (7)	0.0461 (9)	0.0057 (8)
C10	0.0737 (10)	0.0482 (8)	0.0532 (8)	0.0046 (7)	0.0364 (7)	−0.0016 (6)
C11	0.1050 (13)	0.0666 (10)	0.0427 (8)	0.0016 (9)	0.0316 (9)	−0.0134 (7)

Geometric parameters (Å, º) top

O1—C1	1.2355 (14)	C5—C6	1.4005 (17)
O2—C4	1.3015 (17)	C6—C7	1.391 (2)
O2—H2A	0.9200	C6—C11	1.492 (2)
O3—C4	1.2076 (16)	C7—C8	1.373 (2)
N1—C1	1.3387 (14)	C7—H7	0.9300
N1—C5	1.4265 (16)	C8—C9	1.368 (2)
N1—H1N	0.8602	C8—H8	0.9300
C1—C2	1.4779 (18)	C9—C10	1.384 (2)
C2—C3	1.3301 (18)	C9—H9	0.9300
C2—H2	0.9300	C10—H10	0.9300
C3—C4	1.4876 (18)	C11—H11A	0.9600
C3—H3	0.9300	C11—H11B	0.9600
C5—C10	1.3856 (19)	C11—H11C	0.9600

C4—O2—H2A	108.1	C7—C6—C11	120.42 (12)
C1—N1—C5	127.52 (10)	C5—C6—C11	122.15 (12)
C1—N1—H1N	116.3	C8—C7—C6	122.44 (14)
C5—N1—H1N	116.2	C8—C7—H7	118.8
O1—C1—N1	122.54 (11)	C6—C7—H7	118.8
O1—C1—C2	122.32 (10)	C9—C8—C7	119.28 (14)
N1—C1—C2	115.14 (10)	C9—C8—H8	120.4
C3—C2—C1	128.49 (11)	C7—C8—H8	120.4
C3—C2—H2	115.8	C8—C9—C10	120.33 (15)
C1—C2—H2	115.8	C8—C9—H9	119.8
C2—C3—C4	132.88 (12)	C10—C9—H9	119.8
C2—C3—H3	113.6	C9—C10—C5	120.33 (13)
C4—C3—H3	113.6	C9—C10—H10	119.8
O3—C4—O2	120.58 (12)	C5—C10—H10	119.8
O3—C4—C3	119.39 (13)	C6—C11—H11A	109.5
O2—C4—C3	120.03 (11)	C6—C11—H11B	109.5
C10—C5—C6	120.17 (12)	H11A—C11—H11B	109.5
C10—C5—N1	122.04 (11)	C6—C11—H11C	109.5
C6—C5—N1	117.77 (11)	H11A—C11—H11C	109.5
C7—C6—C5	117.43 (13)	H11B—C11—H11C	109.5

C5—N1—C1—O1	−0.5 (2)	N1—C5—C6—C7	179.30 (12)
C5—N1—C1—C2	179.87 (12)	C10—C5—C6—C11	−179.25 (14)
O1—C1—C2—C3	5.8 (2)	N1—C5—C6—C11	−0.7 (2)
N1—C1—C2—C3	−174.52 (14)	C5—C6—C7—C8	0.3 (2)
C1—C2—C3—C4	2.1 (3)	C11—C6—C7—C8	−179.68 (15)
C2—C3—C4—O3	175.97 (16)	C6—C7—C8—C9	−0.8 (2)
C2—C3—C4—O2	−4.1 (3)	C7—C8—C9—C10	0.2 (2)
C1—N1—C5—C10	−17.3 (2)	C8—C9—C10—C5	0.9 (2)
C1—N1—C5—C6	164.21 (12)	C6—C5—C10—C9	−1.4 (2)
C10—C5—C6—C7	0.8 (2)	N1—C5—C10—C9	−179.82 (13)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O3ⁱ	0.86	2.22	3.0665 (14)	167
O2—H2A···O1	0.92	1.56	2.4822 (13)	178

Symmetry code: (i) x, −y+3/2, z−1/2.

Experimental details

Crystal data
Chemical formula	C₁₁H₁₁NO₃
M_r	205.21
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	295
a, b, c (Å)	7.3942 (3), 11.5898 (4), 12.9903 (3)
β (°)	114.534 (2)
V (Å³)	1012.72 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.58 × 0.42 × 0.42

Data collection
Diffractometer	Oxford Diffraction Gemini R CCD diffractometer
Absorption correction	Analytical (CrysAlis PRO; Oxford Diffraction, 2009)
T_min, T_max	0.922, 0.962
No. of measured, independent and observed [I > 2σ(I)] reflections	15644, 1776, 1453
R_int	0.027
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.034, 0.098, 1.07
No. of reflections	1776
No. of parameters	137
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.17, −0.13

Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2002), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O3ⁱ	0.86	2.22	3.0665 (14)	166.7
O2—H2A···O1	0.92	1.56	2.4822 (13)	177.5

Symmetry code: (i) x, −y+3/2, z−1/2.

Acknowledgements

MT and JK thank the Grant Agency of the Slovak Republic (VEGA 1/0817/08) and the Structural Funds, Interreg IIIA, for financial support in purchasing the diffractometer. K. thanks the University Grants Commission, Government of India, New Delhi, for the award of a research fellowship under its faculty improvement program.

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