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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 69| Part 1| January 2013| Pages o94-o95

2-Amino-5-methyl­pyridinium 4-methyl­benzoate

aSchool of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bDepartment of Physics, Faculty of Science, University of Mazandaran, Babolsar, Iran
*Correspondence e-mail: arazaki@usm.my

(Received 4 December 2012; accepted 11 December 2012; online 15 December 2012)

The 4-methyl­benzoate anion of the title salt, C6H9N2+·C8H7O2, is nearly planar, with a dihedral angle of 6.26 (10)° between the benzene ring and the carboxyl­ate group. In the crystal, the protonated N atom and the 2-amino group of the cation are hydrogen bonded to the carboxyl­ate O atoms of the anion via a pair of N—H⋯O hydrogen bonds with an R22(8) ring motif, forming an approximately planar ion pair with a dihedral angle of 9.63 (4)° between the pyridinium and benzene rings. The ion pairs are further connected via N—H⋯O and weak C—H⋯O hydrogen bonds, forming a two-dimensional network parallel to the bc plane.

Related literature

For background to the chemistry of substituted pyridines, see: Pozharski et al. (1997[Pozharski, A. F., Soldatenkov, A. T. & Katritzky, A. R. (1997). In Heterocycles in Life and Society. New York: Wiley.]); Katritzky et al. (1996[Katritzky, A. R., Rees, C. W. & Scriven, E. F. V. (1996). In Comprehensive Heterocyclic Chemistry II. Oxford: Pergamon Press.]). For related structures, see: Nahringbauer & Kvick (1977[Nahringbauer, I. & Kvick, Å. (1977). Acta Cryst. B33, 2902-2905.]); Thanigaimani et al. (2012a[Thanigaimani, K., Farhadikoutenaei, A., Khalib, N. C., Arshad, S. & Razak, I. A. (2012a). Acta Cryst. E68, o3151-o3152.],b[Thanigaimani, K., Farhadikoutenaei, A., Khalib, N. C., Arshad, S. & Razak, I. A. (2012b). Acta Cryst. E68, o3195.],c[Thanigaimani, K., Farhadikoutenaei, A., Khalib, N. C., Arshad, S. & Razak, I. A. (2012c). Acta Cryst. E68, o3196-o3197.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.]).

[Scheme 1]

Experimental

Crystal data
  • C6H9N2+·C8H7O2

  • Mr = 244.29

  • Monoclinic, P 21 /c

  • a = 9.6315 (5) Å

  • b = 10.8713 (6) Å

  • c = 12.1481 (7) Å

  • β = 104.093 (1)°

  • V = 1233.71 (12) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 100 K

  • 0.52 × 0.32 × 0.15 mm

Data collection
  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.955, Tmax = 0.987

  • 18139 measured reflections

  • 4493 independent reflections

  • 3783 reflections with I > 2σ(I)

  • Rint = 0.027

Refinement
  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.125

  • S = 1.03

  • 4493 reflections

  • 177 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.43 e Å−3

  • Δρmin = −0.29 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H1N2⋯O2i 0.920 (16) 1.832 (16) 2.7469 (11) 172.7 (15)
N2—H2N2⋯O1ii 0.926 (16) 1.919 (17) 2.8424 (11) 175.4 (15)
N1—H1N1⋯O1i 0.976 (18) 1.751 (18) 2.7224 (10) 173.1 (16)
C10—H10A⋯O2iii 0.95 2.34 3.1120 (11) 138
Symmetry codes: (i) x+1, y-1, z+1; (ii) [x+1, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (iii) [-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Pyridine and its derivatives play an important role in heterocyclic chemistry (Pozharski et al., 1997; Katritzky et al., 1996). They are often involved in hydrogen-bond interactions. Related crystal structures of 2-amino-5-methylpyridine (Nahringbauer & Kvick, 1977), 2-amino-5-methylpyridinium 6-oxo-1,6-dihydropyridine-2-carboxylate (Thanigaimani et al., 2012a), 2-amino-5-methylpyridinium 3-chlorobenzoate (Thanigaimani et al., 2012b) and 2-amino-5-methylpyridinium 2-aminobenzoate (Thanigaimani et al., 2012c) have been reported. In order to study potential hydrogen bonding interactions, the crystal structure determination of the title compound (I) was carried out.

The asymmetric unit (Fig. 1) contains one 2-amino-5-methylpyridinium cation and one 4-methylbenzoate anion. In the 2-amino-5-methylpyridinium cation, a wider than normal angle [C9—N1—C13 = 122.15 (8)°] is subtended at the protonated N1 atom. The 2-amino-5-methylpyridinium cation is planar with a maximum deviation of 0.005 (1) Å for atom C9. The dihedral angle between the pyridine (N1/C9–C13) and benzene (C1–C6) rings is 9.63 (4)°. The bond lengths (Allen et al., 1987) and angles are normal. In the crystal packing (Fig. 2), the protonated N1 atom and a nitrogen atom of the 2-amino group (N2) are hydrogen-bonded to the carboxylate oxygen atoms (O1 and O2) via a pair of intermolecular N1—H1N1···O1i and N2—H1N2···O2i hydrogen bonds (symmetry code in Table 1), forming a ring motif R22(8) (Bernstein et al., 1995). Furthermore, these motifs are connected via N2—H2N2···O1ii and C10—H10A···O2iii hydrogen bonds (symmetry codes in Table 1), to form a two-dimensional network parallel to the bc plane.

Related literature top

For background to the chemistry of substituted pyridines, see: Pozharski et al. (1997); Katritzky et al. (1996). For related structures, see: Nahringbauer & Kvick (1977); Thanigaimani et al. (2012a,b,c). For hydrogen-bond motifs, see: Bernstein et al. (1995). For bond-length data, see: Allen et al. (1987). For stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986).

Experimental top

Hot methanol solutions (20 ml) of 2-amino5-methylpyridine (54 mg, Aldrich) and 4-methylbenzoic acid (34 mg, Merck) were mixed and warmed over a heating magnetic stirrer hotplate for a few minutes. The resulting solution was allowed to cool slowly at room temperature and crystals of the title compound (I) appeared after a few days.

Refinement top

N-bound H Atoms were located in a difference Fourier maps and refined freely [refined N—H distances 0.976 (18), 0.920 (16) and 0.926 (16) Å]. The remaining hydrogen atoms were positioned geometrically (C—H = 0.95 or 0.98 Å) and were refined using a riding model, with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C). A rotating group model was used for the methyl group.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: 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).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with atom labels with 50% probability displacement ellipsoids.
[Figure 2] Fig. 2. A crystal packing diagram of the title compound. H atoms not involved in the intermolecular interactions (dashed lines) have been omitted for clarity.
2-Amino-5-methylpyridinium 4-methylbenzoate top
Crystal data top
C6H9N2+·C8H7O2F(000) = 520
Mr = 244.29Dx = 1.315 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 6272 reflections
a = 9.6315 (5) Åθ = 2.6–32.6°
b = 10.8713 (6) ŵ = 0.09 mm1
c = 12.1481 (7) ÅT = 100 K
β = 104.093 (1)°Block, colourless
V = 1233.71 (12) Å30.52 × 0.32 × 0.15 mm
Z = 4
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
4493 independent reflections
Radiation source: fine-focus sealed tube3783 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.027
ϕ and ω scansθmax = 32.7°, θmin = 2.6°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 1414
Tmin = 0.955, Tmax = 0.987k = 1616
18139 measured reflectionsl = 1818
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.125H atoms treated by a mixture of independent and constrained refinement
S = 1.03 w = 1/[σ2(Fo2) + (0.0678P)2 + 0.3153P]
where P = (Fo2 + 2Fc2)/3
4493 reflections(Δ/σ)max = 0.001
177 parametersΔρmax = 0.43 e Å3
0 restraintsΔρmin = 0.29 e Å3
Crystal data top
C6H9N2+·C8H7O2V = 1233.71 (12) Å3
Mr = 244.29Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.6315 (5) ŵ = 0.09 mm1
b = 10.8713 (6) ÅT = 100 K
c = 12.1481 (7) Å0.52 × 0.32 × 0.15 mm
β = 104.093 (1)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
4493 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
3783 reflections with I > 2σ(I)
Tmin = 0.955, Tmax = 0.987Rint = 0.027
18139 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.125H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.43 e Å3
4493 reflectionsΔρmin = 0.29 e Å3
177 parameters
Special details top

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 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
xyzUiso*/Ueq
O10.07967 (7)1.13827 (6)0.07082 (5)0.01774 (14)
O20.20480 (8)1.12140 (6)0.06122 (6)0.01914 (15)
C10.23323 (9)0.93283 (8)0.19086 (7)0.01486 (16)
H1A0.16130.96800.22240.018*
C20.31890 (10)0.83760 (8)0.24780 (7)0.01618 (16)
H2A0.30480.80900.31820.019*
C30.42490 (9)0.78366 (8)0.20317 (7)0.01589 (16)
C40.44248 (10)0.82614 (9)0.09878 (8)0.01896 (18)
H4A0.51320.79000.06650.023*
C50.35734 (10)0.92094 (9)0.04167 (7)0.01693 (17)
H5A0.37020.94840.02940.020*
C60.25310 (9)0.97626 (8)0.08768 (7)0.01277 (15)
C70.17236 (9)1.08592 (8)0.02773 (7)0.01374 (15)
C80.51917 (10)0.68238 (9)0.26587 (8)0.02109 (19)
H8A0.52150.68690.34690.032*
H8B0.61640.69210.25560.032*
H8C0.48080.60240.23580.032*
N10.94348 (8)0.32387 (7)0.93651 (6)0.01462 (15)
N21.04273 (9)0.28128 (8)0.78450 (7)0.01928 (16)
C90.95687 (9)0.35009 (8)0.83058 (7)0.01471 (16)
C100.87654 (10)0.45002 (9)0.77234 (7)0.01714 (17)
H10A0.88250.47030.69760.021*
C110.79056 (10)0.51697 (8)0.82424 (8)0.01771 (17)
H11A0.73730.58390.78470.021*
C120.77883 (9)0.48901 (8)0.93576 (8)0.01643 (16)
C130.85738 (9)0.39091 (8)0.98802 (7)0.01558 (16)
H13A0.85170.36891.06250.019*
C140.68490 (11)0.56433 (9)0.99240 (9)0.02191 (19)
H14A0.68590.52871.06670.033*
H14B0.58670.56440.94500.033*
H14C0.72090.64891.00240.033*
H1N21.0977 (16)0.2237 (15)0.8310 (13)0.035 (4)*
H2N21.0599 (17)0.3085 (15)0.7168 (14)0.035 (4)*
H1N10.9942 (18)0.2547 (17)0.9795 (15)0.046 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0208 (3)0.0182 (3)0.0149 (3)0.0068 (2)0.0055 (2)0.0002 (2)
O20.0245 (3)0.0186 (3)0.0158 (3)0.0042 (2)0.0075 (2)0.0036 (2)
C10.0150 (4)0.0143 (4)0.0157 (4)0.0013 (3)0.0046 (3)0.0008 (3)
C20.0175 (4)0.0155 (4)0.0156 (4)0.0011 (3)0.0041 (3)0.0021 (3)
C30.0149 (4)0.0135 (4)0.0182 (4)0.0011 (3)0.0021 (3)0.0004 (3)
C40.0179 (4)0.0184 (4)0.0221 (4)0.0052 (3)0.0076 (3)0.0013 (3)
C50.0184 (4)0.0174 (4)0.0162 (4)0.0030 (3)0.0064 (3)0.0015 (3)
C60.0129 (3)0.0119 (3)0.0131 (3)0.0002 (3)0.0023 (3)0.0007 (3)
C70.0157 (4)0.0127 (3)0.0122 (3)0.0002 (3)0.0021 (3)0.0012 (3)
C80.0197 (4)0.0171 (4)0.0249 (4)0.0044 (3)0.0024 (3)0.0035 (3)
N10.0161 (3)0.0144 (3)0.0134 (3)0.0003 (2)0.0037 (2)0.0022 (2)
N20.0229 (4)0.0206 (4)0.0159 (3)0.0040 (3)0.0076 (3)0.0036 (3)
C90.0158 (4)0.0146 (4)0.0135 (3)0.0019 (3)0.0032 (3)0.0012 (3)
C100.0187 (4)0.0170 (4)0.0151 (4)0.0001 (3)0.0028 (3)0.0044 (3)
C110.0172 (4)0.0149 (4)0.0203 (4)0.0003 (3)0.0032 (3)0.0036 (3)
C120.0149 (4)0.0144 (4)0.0198 (4)0.0014 (3)0.0041 (3)0.0001 (3)
C130.0165 (4)0.0160 (4)0.0146 (4)0.0012 (3)0.0043 (3)0.0003 (3)
C140.0203 (4)0.0207 (4)0.0259 (4)0.0030 (3)0.0077 (3)0.0002 (3)
Geometric parameters (Å, º) top
O1—C71.2737 (10)N1—C91.3545 (11)
O2—C71.2564 (11)N1—C131.3649 (11)
C1—C61.3956 (12)N1—H1N10.976 (18)
C1—C21.3975 (12)N2—C91.3351 (12)
C1—H1A0.9500N2—H1N20.920 (16)
C2—C31.3962 (13)N2—H2N20.926 (16)
C2—H2A0.9500C9—C101.4187 (12)
C3—C41.3981 (13)C10—C111.3665 (13)
C3—C81.5100 (12)C10—H10A0.9500
C4—C51.3924 (12)C11—C121.4195 (13)
C4—H4A0.9500C11—H11A0.9500
C5—C61.3984 (12)C12—C131.3708 (12)
C5—H5A0.9500C12—C141.5052 (13)
C6—C71.5101 (12)C13—H13A0.9500
C8—H8A0.9800C14—H14A0.9800
C8—H8B0.9800C14—H14B0.9800
C8—H8C0.9800C14—H14C0.9800
C6—C1—C2120.10 (8)C9—N1—C13122.15 (8)
C6—C1—H1A120.0C9—N1—H1N1121.3 (10)
C2—C1—H1A120.0C13—N1—H1N1116.6 (10)
C3—C2—C1121.23 (8)C9—N2—H1N2116.5 (10)
C3—C2—H2A119.4C9—N2—H2N2117.1 (10)
C1—C2—H2A119.4H1N2—N2—H2N2124.3 (14)
C2—C3—C4118.36 (8)N2—C9—N1119.50 (8)
C2—C3—C8121.14 (8)N2—C9—C10122.56 (8)
C4—C3—C8120.51 (8)N1—C9—C10117.94 (8)
C5—C4—C3120.64 (8)C11—C10—C9119.73 (8)
C5—C4—H4A119.7C11—C10—H10A120.1
C3—C4—H4A119.7C9—C10—H10A120.1
C4—C5—C6120.81 (8)C10—C11—C12121.62 (8)
C4—C5—H5A119.6C10—C11—H11A119.2
C6—C5—H5A119.6C12—C11—H11A119.2
C1—C6—C5118.84 (8)C13—C12—C11116.45 (8)
C1—C6—C7122.21 (7)C13—C12—C14122.48 (8)
C5—C6—C7118.84 (7)C11—C12—C14121.08 (8)
O2—C7—O1124.21 (8)N1—C13—C12122.11 (8)
O2—C7—C6116.77 (8)N1—C13—H13A118.9
O1—C7—C6118.99 (7)C12—C13—H13A118.9
C3—C8—H8A109.5C12—C14—H14A109.5
C3—C8—H8B109.5C12—C14—H14B109.5
H8A—C8—H8B109.5H14A—C14—H14B109.5
C3—C8—H8C109.5C12—C14—H14C109.5
H8A—C8—H8C109.5H14A—C14—H14C109.5
H8B—C8—H8C109.5H14B—C14—H14C109.5
C6—C1—C2—C30.32 (13)C1—C6—C7—O12.27 (12)
C1—C2—C3—C40.82 (13)C5—C6—C7—O1178.40 (8)
C1—C2—C3—C8178.86 (8)C13—N1—C9—N2179.99 (8)
C2—C3—C4—C50.77 (14)C13—N1—C9—C100.73 (13)
C8—C3—C4—C5178.91 (9)N2—C9—C10—C11179.98 (9)
C3—C4—C5—C60.41 (14)N1—C9—C10—C110.77 (13)
C2—C1—C6—C51.49 (13)C9—C10—C11—C120.17 (14)
C2—C1—C6—C7174.64 (8)C10—C11—C12—C130.48 (13)
C4—C5—C6—C11.54 (13)C10—C11—C12—C14179.36 (9)
C4—C5—C6—C7174.72 (8)C9—N1—C13—C120.07 (13)
C1—C6—C7—O2175.94 (8)C11—C12—C13—N10.54 (13)
C5—C6—C7—O20.19 (12)C14—C12—C13—N1179.30 (8)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H1N2···O2i0.920 (16)1.832 (16)2.7469 (11)172.7 (15)
N2—H2N2···O1ii0.926 (16)1.919 (17)2.8424 (11)175.4 (15)
N1—H1N1···O1i0.976 (18)1.751 (18)2.7224 (10)173.1 (16)
C10—H10A···O2iii0.952.343.1120 (11)138
Symmetry codes: (i) x+1, y1, z+1; (ii) x+1, y+3/2, z+1/2; (iii) x+1, y1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC6H9N2+·C8H7O2
Mr244.29
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)9.6315 (5), 10.8713 (6), 12.1481 (7)
β (°) 104.093 (1)
V3)1233.71 (12)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.52 × 0.32 × 0.15
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.955, 0.987
No. of measured, independent and
observed [I > 2σ(I)] reflections
18139, 4493, 3783
Rint0.027
(sin θ/λ)max1)0.759
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.125, 1.03
No. of reflections4493
No. of parameters177
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.43, 0.29

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H1N2···O2i0.920 (16)1.832 (16)2.7469 (11)172.7 (15)
N2—H2N2···O1ii0.926 (16)1.919 (17)2.8424 (11)175.4 (15)
N1—H1N1···O1i0.976 (18)1.751 (18)2.7224 (10)173.1 (16)
C10—H10A···O2iii0.952.343.1120 (11)138
Symmetry codes: (i) x+1, y1, z+1; (ii) x+1, y+3/2, z+1/2; (iii) x+1, y1/2, z+1/2.
 

Footnotes

Thomson Reuters ResearcherID: A-5599-2009.

Acknowledgements

The authors thank the Malaysian Government and Universiti Sains Malaysia (USM) for the research facilities and USM Short Term Grant No. 304/PFIZIK/6312078 to conduct this work. KT thanks The Academy of Sciences for the Developing World and USM for a TWAS–USM fellowship.

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Volume 69| Part 1| January 2013| Pages o94-o95
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