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2-Amino-5-methyl­pyridinium nicotinate

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: hkfun@usm.my

(Received 8 February 2010; accepted 14 February 2010; online 20 February 2010)

In the title compound, C6H9N2+·C6H4NO2, the 2-amino-5-methyl­pyridinium cation is essentially planar, with a maximum deviation of 0.023 (2) Å. In the crystal, the cations and anions are linked via strong N—H⋯O hydrogen bonds, forming a two dimensional network parallel to (100). In addition, ππ inter­actions involving the pyridinium and pyridine rings, with centroid–centroid distances of 3.6383 (8) Å, are observed.

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). Heterocycles in Life and Society. New York: Wiley.]); Katritzky et al. (1996[Katritzky, A. R., Rees, C. W. & Scriven, E. F. V. (1996). Comprehensive Heterocyclic Chemistry II. Oxford: Pergamon Press.]). For nicotinic acid, see: Athimoolam & Rajaram (2005[Athimoolam, S. & Rajaram, R. K. (2005). Acta Cryst. E61, o2764-o2767.]); Lorenzen et al. (2001[Lorenzen, A., Stannek, C., Lang, H., Andrianov, V., Kalvinsh, I. & Schwabe, U. (2001). Mol. Pharmacol. 59, 349-357.]); Gielen et al. (1992[Gielen, M., Khloufi, A. E., Biesemans, M. & Willem, R. (1992). Polyhedron, 11, 1861-1868.]); Kim et al. (2004[Kim, H.-L., Yoon, H.-J., Ha, J. Y., Lee, B. I., Lee, H. H., Mikami, B. & Suh, S. W. (2004). Acta Cryst. D60, 948-949.]). For a related structure, see: Nahringbauer & Kvick (1977[Nahringbauer, I. & Kvick, Å. (1977). Acta Cryst. B33, 2902-2905.]). For details of hydrogen bonding, see: Jeffrey & Saenger (1991[Jeffrey, G. A. & Saenger, W. (1991). Hydrogen Bonding in Biological Structures. Berlin: Springer.]); Jeffrey (1997[Jeffrey, G. A. (1997). An Introduction to Hydrogen Bonding. Oxford University Press.]); Scheiner (1997[Scheiner, S. (1997). Hydrogen Bonding. A Theoretical Perspective. Oxford University Press.]). 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.]).

[Scheme 1]

Experimental

Crystal data
  • C6H9N2+·C6H4NO2

  • Mr = 231.25

  • Monoclinic, P 21 /c

  • a = 9.4877 (3) Å

  • b = 11.1403 (3) Å

  • c = 11.7611 (3) Å

  • β = 110.113 (2)°

  • V = 1167.29 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 296 K

  • 0.63 × 0.11 × 0.11 mm

Data collection
  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.944, Tmax = 0.990

  • 14482 measured reflections

  • 3870 independent reflections

  • 2240 reflections with I > 2σ(I)

  • Rint = 0.026

Refinement
  • R[F2 > 2σ(F2)] = 0.050

  • wR(F2) = 0.144

  • S = 1.05

  • 3870 reflections

  • 195 parameters

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

  • Δρmax = 0.20 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N1⋯O2i 0.988 (16) 1.703 (16) 2.6899 (15) 176.8 (16)
N2—H1N2⋯O2ii 0.883 (16) 1.999 (16) 2.8756 (17) 171.7 (15)
N2—H2N2⋯O1i 0.936 (18) 1.878 (18) 2.8122 (17) 176.6 (17)
Symmetry codes: (i) x-1, y, z-1; (ii) [x-1, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. 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 important roles in heterocyclic chemistry (Pozharski et al., 1997; Katritzky et al., 1996). They are often involved in hydrogen-bond interactions (Jeffrey & Saenger, 1991; Jeffrey, 1997; Scheiner, 1997). Nicotinic acid (vitamin B3), known as niacin, is a lipid lowering agent widely used to treat hypertriglyceridemia by the inhibition of lipolysis in adipose tissue (Athimoolam & Rajaram, 2005). The nicotinic acid complex 5-methylpyrazine-2-carboxylic acid-4-oxide is a commonly used drug for the treatment of hypercholesterolemia (Lorenzen et al., 2001). Coordination complexes of nicotinic acid with metals such as Sn possess antitumour activity greater than the well known cisplatin or doxorubicin (Gielen et al., 1992). The enzyme nicotinic acid mononucleotide adenyltransferase is essential for the synthesis of nicotinamide adenine dinucleotide in all living cells and is a potential target for antibiotics (Kim et al., 2004). Since our aim is to study some interesting hydrogen bonding interactions, the crystal structure of the title compound is presented here.

The asymmetric unit (Fig. 1) contains one 2-amino-5-methylpyridinium cation and one nicotinate anion. The proton transfer from the carboxyl group to atom N1 of 2-amino-5-methylpyridine resulted in the widening of C1—N1—C5 angle of the pyridinium ring to 122.61 (11)°, compared to the corresponding angle of 117.4° in neutral 2-amino-5-methylpyridine (Nahringbauer & Kvick, 1977). The 2-amino-5-methylpyridinium cation is essentially planar, with a maximum deviation of 0.023 (2)Å for atom C6. The bond lengths are normal (Allen et al., 1987).

In the crystal packing (Fig. 2), the protonated N1 atom and the 2-amino group (N2) is hydrogen-bonded to the carboxylate oxygen atoms (O1 and O2) via a pair of intermolecular N1—H1N1···O2 and N2—H2N2···O1 hydrogen bonds forming an R22(8) ring motif (Bernstein et al., 1995). The intermolecular N2—H1N2···O2 hydrogen bonds connect these molecules into 2-dimensional networks parallel to the (100)-plane (see Table 1). The crystal structure is further stabilized by π···π interactions involving the pyridine (C7–C11/N3) and pyridinium (C1–C5/N1) rings, with centroid to centroid distance of 3.6383 (8)Å [symmetry code: 1-x, 1-y, 1-z].

Related literature top

For background to the chemistry of substituted pyridines, see: Pozharski et al. (1997); Katritzky et al. (1996). For nicotinic acid, see: Athimoolam & Rajaram (2005); Lorenzen et al. (2001); Gielen et al. (1992); Kim et al. (2004). For a related structure, see: Nahringbauer & Kvick (1977). For details of hydrogen bonding, see: Jeffrey & Saenger (1991); Jeffrey (1997); Scheiner (1997). For hydrogen-bond motifs, see: Bernstein et al. (1995). For bond-length data, see: Allen et al. (1987).

Experimental top

A hot methanol solution (20 ml) of 2-amino-5-methylpyridine (54 mg, Aldrich) and nicotinic acid (62 mg, Merck) were mixed and warmed over a heating magnetic stirrer for a few minutes. The resulting solution was allowed to cool slowly at room temperature and crystals of the title compound appeared after a few days.

Refinement top

The methyl H atoms were positioned geometrically and were refined using a riding model, with Uiso(H) = 1.5Ueq(C). A rotating group model was used for the methyl group. The remaining H atoms were located in a difference map and refined freely [N–H = 0.883 (16)–0.988 (16)Å, C–H = 0.946 (13)–1.015 (17)Å].

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 asymmetric unit of the title compound. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. The crystal packing of the title compound, showing hydrogen-bonded (dashed lines) networks.
2-Amino-5-methylpyridinium nicotinate top
Crystal data top
C6H9N2+·C6H4NO2F(000) = 488
Mr = 231.25Dx = 1.316 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 4062 reflections
a = 9.4877 (3) Åθ = 2.6–26.7°
b = 11.1403 (3) ŵ = 0.09 mm1
c = 11.7611 (3) ÅT = 296 K
β = 110.113 (2)°Needle, colourless
V = 1167.29 (6) Å30.63 × 0.11 × 0.11 mm
Z = 4
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
3870 independent reflections
Radiation source: fine-focus sealed tube2240 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.026
ϕ and ω scansθmax = 31.6°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 1313
Tmin = 0.944, Tmax = 0.990k = 1516
14482 measured reflectionsl = 1717
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)] = 0.050Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.144H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.0668P)2 + 0.0299P]
where P = (Fo2 + 2Fc2)/3
3870 reflections(Δ/σ)max < 0.001
195 parametersΔρmax = 0.20 e Å3
0 restraintsΔρmin = 0.20 e Å3
Crystal data top
C6H9N2+·C6H4NO2V = 1167.29 (6) Å3
Mr = 231.25Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.4877 (3) ŵ = 0.09 mm1
b = 11.1403 (3) ÅT = 296 K
c = 11.7611 (3) Å0.63 × 0.11 × 0.11 mm
β = 110.113 (2)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
3870 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
2240 reflections with I > 2σ(I)
Tmin = 0.944, Tmax = 0.990Rint = 0.026
14482 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0500 restraints
wR(F2) = 0.144H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.20 e Å3
3870 reflectionsΔρmin = 0.20 e Å3
195 parameters
Special details top

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
xyzUiso*/Ueq
N10.02188 (12)0.19316 (10)0.05859 (9)0.0442 (3)
N20.10328 (14)0.22434 (12)0.19337 (12)0.0585 (3)
C10.00012 (14)0.16474 (11)0.16305 (10)0.0442 (3)
C20.08966 (14)0.07300 (12)0.23423 (12)0.0491 (3)
C30.19225 (14)0.01646 (12)0.19651 (12)0.0503 (3)
C40.21339 (13)0.04715 (12)0.08710 (11)0.0478 (3)
C50.12592 (14)0.13727 (12)0.02171 (11)0.0459 (3)
C60.33142 (17)0.01226 (17)0.04856 (14)0.0688 (4)
H6A0.33130.02250.02620.103*
H6B0.31050.09660.03730.103*
H6C0.42800.00070.10980.103*
O10.72673 (12)0.39748 (10)1.02919 (8)0.0659 (3)
O20.86277 (12)0.36701 (9)0.91118 (8)0.0617 (3)
N30.68920 (14)0.67197 (11)0.70931 (11)0.0599 (3)
C70.58423 (16)0.73306 (14)0.73619 (15)0.0627 (4)
C80.53402 (17)0.70341 (14)0.82858 (16)0.0661 (4)
C90.59378 (16)0.60379 (13)0.89864 (14)0.0559 (4)
C100.70147 (13)0.53689 (11)0.87228 (11)0.0434 (3)
C110.74469 (15)0.57565 (12)0.77763 (12)0.0514 (3)
C120.76845 (14)0.42525 (11)0.94349 (11)0.0462 (3)
H2A0.0757 (14)0.0528 (11)0.3103 (13)0.053 (4)*
H3A0.2576 (15)0.0480 (13)0.2476 (13)0.059 (4)*
H5A0.1359 (14)0.1651 (11)0.0511 (12)0.047 (3)*
H7A0.5424 (18)0.8056 (15)0.6832 (15)0.076 (5)*
H8A0.458 (2)0.7512 (15)0.8436 (15)0.082 (5)*
H9A0.5651 (16)0.5825 (13)0.9650 (15)0.069 (5)*
H11A0.8211 (16)0.5323 (13)0.7567 (12)0.061 (4)*
H1N10.0397 (17)0.2561 (14)0.0051 (14)0.069 (4)*
H1N20.1231 (16)0.1988 (13)0.2573 (15)0.065 (4)*
H2N20.159 (2)0.2841 (16)0.1413 (16)0.081 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0485 (5)0.0474 (6)0.0391 (5)0.0001 (5)0.0180 (4)0.0027 (5)
N20.0715 (8)0.0654 (8)0.0503 (6)0.0121 (6)0.0358 (6)0.0098 (6)
C10.0494 (6)0.0474 (7)0.0389 (6)0.0066 (5)0.0191 (5)0.0013 (5)
C20.0515 (7)0.0553 (8)0.0425 (6)0.0048 (6)0.0186 (5)0.0082 (6)
C30.0462 (7)0.0532 (8)0.0502 (7)0.0018 (6)0.0150 (6)0.0085 (6)
C40.0437 (6)0.0549 (8)0.0461 (7)0.0036 (6)0.0171 (5)0.0009 (6)
C50.0468 (7)0.0558 (8)0.0380 (6)0.0039 (6)0.0183 (5)0.0002 (6)
C60.0611 (8)0.0880 (11)0.0618 (9)0.0186 (8)0.0268 (7)0.0076 (8)
O10.0818 (7)0.0743 (7)0.0557 (6)0.0160 (5)0.0417 (5)0.0135 (5)
O20.0788 (6)0.0671 (6)0.0499 (5)0.0249 (5)0.0358 (5)0.0115 (4)
N30.0668 (7)0.0543 (7)0.0576 (7)0.0011 (6)0.0199 (6)0.0071 (6)
C70.0590 (8)0.0479 (8)0.0726 (10)0.0014 (7)0.0117 (7)0.0052 (7)
C80.0556 (8)0.0504 (8)0.0954 (12)0.0041 (7)0.0299 (8)0.0050 (8)
C90.0571 (8)0.0506 (8)0.0680 (9)0.0019 (6)0.0318 (7)0.0043 (7)
C100.0427 (6)0.0455 (7)0.0425 (6)0.0028 (5)0.0154 (5)0.0048 (5)
C110.0545 (7)0.0530 (8)0.0495 (7)0.0018 (6)0.0214 (6)0.0005 (6)
C120.0519 (7)0.0514 (8)0.0376 (6)0.0001 (6)0.0185 (5)0.0050 (5)
Geometric parameters (Å, º) top
N1—C11.3526 (14)C6—H6B0.9600
N1—C51.3582 (16)C6—H6C0.9600
N1—H1N10.988 (16)O1—C121.2420 (14)
N2—C11.3289 (17)O2—C121.2650 (15)
N2—H1N20.883 (16)N3—C71.331 (2)
N2—H2N20.936 (19)N3—C111.3354 (17)
C1—C21.4073 (18)C7—C81.368 (2)
C2—C31.3558 (18)C7—H7A1.015 (17)
C2—H2A0.974 (14)C8—C91.382 (2)
C3—C41.4108 (18)C8—H8A0.964 (18)
C3—H3A1.002 (14)C9—C101.3832 (18)
C4—C51.3598 (18)C9—H9A0.941 (16)
C4—C61.4989 (19)C10—C111.3812 (17)
C5—H5A0.946 (13)C10—C121.5121 (18)
C6—H6A0.9600C11—H11A0.970 (15)
C1—N1—C5122.61 (11)H6A—C6—H6B109.5
C1—N1—H1N1120.1 (8)C4—C6—H6C109.5
C5—N1—H1N1117.3 (8)H6A—C6—H6C109.5
C1—N2—H1N2117.4 (10)H6B—C6—H6C109.5
C1—N2—H2N2119.0 (10)C7—N3—C11116.12 (13)
H1N2—N2—H2N2123.2 (14)N3—C7—C8123.94 (14)
N2—C1—N1118.99 (12)N3—C7—H7A115.3 (9)
N2—C1—C2123.65 (11)C8—C7—H7A120.7 (9)
N1—C1—C2117.35 (11)C7—C8—C9118.93 (14)
C3—C2—C1119.90 (12)C7—C8—H8A120.1 (10)
C3—C2—H2A122.2 (7)C9—C8—H8A120.9 (10)
C1—C2—H2A117.9 (7)C8—C9—C10118.82 (14)
C2—C3—C4121.95 (13)C8—C9—H9A121.4 (9)
C2—C3—H3A120.2 (8)C10—C9—H9A119.8 (9)
C4—C3—H3A117.9 (8)C11—C10—C9117.33 (13)
C5—C4—C3116.37 (12)C11—C10—C12121.26 (11)
C5—C4—C6121.94 (12)C9—C10—C12121.41 (12)
C3—C4—C6121.61 (12)N3—C11—C10124.84 (13)
N1—C5—C4121.81 (12)N3—C11—H11A114.9 (8)
N1—C5—H5A116.7 (8)C10—C11—H11A120.2 (8)
C4—C5—H5A121.5 (8)O1—C12—O2124.88 (12)
C4—C6—H6A109.5O1—C12—C10117.64 (11)
C4—C6—H6B109.5O2—C12—C10117.48 (10)
C5—N1—C1—N2179.41 (11)N3—C7—C8—C90.5 (2)
C5—N1—C1—C20.22 (18)C7—C8—C9—C100.5 (2)
N2—C1—C2—C3179.87 (12)C8—C9—C10—C111.1 (2)
N1—C1—C2—C30.52 (18)C8—C9—C10—C12178.48 (12)
C1—C2—C3—C40.4 (2)C7—N3—C11—C100.3 (2)
C2—C3—C4—C50.46 (19)C9—C10—C11—N30.7 (2)
C2—C3—C4—C6177.42 (13)C12—C10—C11—N3178.87 (12)
C1—N1—C5—C41.14 (19)C11—C10—C12—O1178.34 (12)
C3—C4—C5—N11.21 (18)C9—C10—C12—O12.15 (19)
C6—C4—C5—N1178.16 (12)C11—C10—C12—O21.73 (19)
C11—N3—C7—C80.9 (2)C9—C10—C12—O2177.79 (12)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N1···O2i0.988 (16)1.703 (16)2.6899 (15)176.8 (16)
N2—H1N2···O2ii0.883 (16)1.999 (16)2.8756 (17)171.7 (15)
N2—H2N2···O1i0.936 (18)1.878 (18)2.8122 (17)176.6 (17)
Symmetry codes: (i) x1, y, z1; (ii) x1, y+1/2, z1/2.

Experimental details

Crystal data
Chemical formulaC6H9N2+·C6H4NO2
Mr231.25
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)9.4877 (3), 11.1403 (3), 11.7611 (3)
β (°) 110.113 (2)
V3)1167.29 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.63 × 0.11 × 0.11
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.944, 0.990
No. of measured, independent and
observed [I > 2σ(I)] reflections
14482, 3870, 2240
Rint0.026
(sin θ/λ)max1)0.736
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.050, 0.144, 1.05
No. of reflections3870
No. of parameters195
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.20, 0.20

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
N1—H1N1···O2i0.988 (16)1.703 (16)2.6899 (15)176.8 (16)
N2—H1N2···O2ii0.883 (16)1.999 (16)2.8756 (17)171.7 (15)
N2—H2N2···O1i0.936 (18)1.878 (18)2.8122 (17)176.6 (17)
Symmetry codes: (i) x1, y, z1; (ii) x1, y+1/2, z1/2.
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

MH and HKF thank the Malaysian Government and Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012. MH thanks Universiti Sains Malaysia for a post-doctoral research fellowship.

References

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