2-Amino-6-methyl­pyridinium 4-hy­droxy­benzoate

Kannan, V.; Sugumar, P.; Brahadeeswaran, S.; Ponnuswamy, M.N.

doi:10.1107/S1600536813007939

organic compounds

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ISSN: 2056-9890

Volume 69| Part 4| April 2013| Page o610

doi:10.1107/S1600536813007939

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2-Amino-6-methylpyridinium 4-hydroxybenzoate

V. Kannan,^a P. Sugumar,^b S. Brahadeeswaran ^c and M. N. Ponnuswamy ^b ^*

^aDepartment of Physics, M.A.M. School of Engineering, Siruganur, Tiruchirappalli 621 105, India, ^bCentre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India, and ^cDepartment of Physics, Anna University, BIT Campus, Tiruchirappalli 620 024, India
^*Correspondence e-mail: mnpsy2004@yahoo.com

(Received 6 November 2012; accepted 21 March 2013; online 28 March 2013)

In the title molecular salt, C₆H₉N₂⁺·C₇H₅O₃⁻, the dihedral angle between the benzene ring and the CO₂ group in the anion is 6.1 (2)°. In the crystal, the cation and anion are linked by N—H⋯O and C—H⋯O hydrogen bonds, and the anions are connected by O—H⋯O hydrogen bonds, forming a three-dimensional network.

Related literature

For general background to methylpyridinium derivatives, see: Blessing (1986 ); Brahadeeswaran et al. (2006 ); Brown (1976 ); Kvenvolden et al. (1971 ); Tomaru et al. (1991 ).

Experimental

Crystal data

C₆H₉N₂⁺·C₇H₅O₃⁻
M_r = 246.26
Monoclinic, P 2₁ /c
a = 11.9488 (3) Å
b = 9.2952 (3) Å
c = 12.4067 (3) Å
β = 117.116 (2)°
V = 1226.51 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 293 K
0.20 × 0.18 × 0.17 mm

Data collection

Bruker SMART APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2008 ) T_min = 0.981, T_max = 0.984
11403 measured reflections
3084 independent reflections
2471 reflections with I > 2σ(I)
R_int = 0.023

Refinement

R[F² > 2σ(F²)] = 0.041
wR(F²) = 0.122
S = 1.04
3084 reflections
168 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.25 e Å⁻³
Δρ_min = −0.20 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O1ⁱ	0.86	2.00	2.8499 (13)	169
N2—H2A⋯O2ⁱ	0.86	1.94	2.7879 (14)	168
N2—H2B⋯O1ⁱⁱ	0.86	2.18	2.9902 (14)	157
O3—H3A⋯O2ⁱⁱⁱ	0.97 (2)	1.67 (2)	2.6281 (14)	168.5 (19)
C4—H4⋯O3^iv	0.93	2.51	3.4134 (17)	163
Symmetry codes: (i) -x+1, -y+2, -z+1; (ii) $[-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (iii) $[-x+2, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (iv) -x+2, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ) and DIAMOND (Brandenburg, 1998 ); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536813007939/lx2273sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813007939/lx2273Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813007939/lx2273Isup3.cml

checkCIF report

Comment top

Pyridine heterocycles and their derivatives are present in many large molecules having photo chemical, electro chemical and catalytic applications. Pyridine derivatives possess nonlinear optical (NLO) properties(Tomaru et al., 1991). 4–N,N–dimethylamino–4'–N'–methyl stilbazolium tosylate (DAST) is used in generating and detecting terahertz (THz) frequencies (Brahadeeswaran et al.,2006). Carboxylic acids are believed to have existed in the prebiotic earth (Kvenvolden et al., 1971) and form aggregation patterns. An attempt is made to solve the pyridine based crystal structures to explore the NLO behaviour.

The crystal structure of the title compound (Fig.1) consists of aminomethylpyridinium cation and hydroxybenzoate anion connected via N—H···O & C—H···O hydrogen bonds (Blessing,1986; Brown, 1976). The pyridinium ring is essentially planar, with a maximum deviation of -0.005 (1) Å for atom N1. The dihedral angle between the pyridinium ring in the cation and the benzene ring in the anion is 78.32 (7)°.

In the crystal structure (Fig. 2), the cation and anion are linked by N—H···O and C—H···O hydrogen bonds (Table 1), and the anions are connected by O—H···O hydrogen bonds (Table 1), forming a three–dimensional network.

Related literature top

For general background to methylpyridinium derivatives, see: Blessing (1986); Brahadeeswaran et al. (2006); Brown (1976); Kvenvolden et al. (1971); Tomaru et al. (1991).

Experimental top

Methanol solutions of 2–amino–6–methylpyridine (54 mg) and 4–hydroxybenzoic acid (69 mg) were mixed together and stirred for about 1 h to get a homogeneous mixture. The resulting solution was allowed to evaporate at 303 K slowly in a water bath which has a temperature accuracy of ± 0.01° C at ambient atmosphere. Brownish crystals with developed morphology of title compound were obtained after 15 days.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are presented as small spheres of arbitrary radius.

Fig. 2. A view of the N—H···O, C—H···O and O—H···O hydrogen bonds (dotted lines) in the crystal structure of the title compound. H atoms not participating in hydrogen–bonding were omitted for clarity. [Symmetry code: (i) - x + 1, - y + 2, - z + 1; (ii) - x + 1 , y - 1/2, - z + 1/2; (iii) - x + 2, y - 1/2, - z + 3/2; (iv) - x + 2, - y + 1, - z + 1; (v) - x + 1, - y + 2, - z + 1; (vi) - x + 1, y + 1/2, - z + 1/2; (vii) - x + 2, y + 1/2, - z + 3/2.]

2-Amino-6-methylpyridinium 4-hydroxybenzoate top

Crystal data top

C₆H₉N₂⁺·C₇H₅O₃⁻	F(000) = 520
M_r = 246.26	D_x = 1.334 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2671 reflections
a = 11.9488 (3) Å	θ = 1.9–28.4°
b = 9.2952 (3) Å	µ = 0.10 mm⁻¹
c = 12.4067 (3) Å	T = 293 K
β = 117.116 (2)°	Block, white crystalline
V = 1226.51 (6) Å³	0.20 × 0.18 × 0.17 mm
Z = 4

Data collection top

Bruker SMART APEXII CCD diffractometer	3084 independent reflections
Radiation source: fine-focus sealed tube	2471 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.023
ω and ϕ scans	θ_max = 28.4°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −16→15
T_min = 0.981, T_max = 0.984	k = −10→12
11403 measured reflections	l = −16→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)] = 0.041	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.122	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ²(F_o²) + (0.0582P)² + 0.2532P] where P = (F_o² + 2F_c²)/3
3084 reflections	(Δ/σ)_max < 0.001
168 parameters	Δρ_max = 0.25 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³

Crystal data top

C₆H₉N₂⁺·C₇H₅O₃⁻	V = 1226.51 (6) Å³
M_r = 246.26	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 11.9488 (3) Å	µ = 0.10 mm⁻¹
b = 9.2952 (3) Å	T = 293 K
c = 12.4067 (3) Å	0.20 × 0.18 × 0.17 mm
β = 117.116 (2)°

Data collection top

Bruker SMART APEXII CCD diffractometer	3084 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2008)	2471 reflections with I > 2σ(I)
T_min = 0.981, T_max = 0.984	R_int = 0.023
11403 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.041	0 restraints
wR(F²) = 0.122	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	Δρ_max = 0.25 e Å⁻³
3084 reflections	Δρ_min = −0.20 e Å⁻³
168 parameters

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
C2	0.63520 (11)	0.65353 (14)	0.57200 (11)	0.0399 (3)
C3	0.72343 (13)	0.56067 (17)	0.57177 (14)	0.0528 (3)
H3	0.7947	0.5393	0.6434	0.063*
C4	0.70557 (14)	0.49803 (16)	0.46291 (15)	0.0562 (4)
H4	0.7652	0.4342	0.4623	0.067*
C5	0.60208 (14)	0.52912 (14)	0.35780 (13)	0.0486 (3)
H5	0.5912	0.4868	0.2857	0.058*
C6	0.51139 (12)	0.62547 (13)	0.35806 (11)	0.0384 (3)
C7	0.64299 (12)	0.72809 (17)	0.68095 (12)	0.0490 (3)
H7A	0.5776	0.6934	0.6988	0.074*
H7B	0.6331	0.8298	0.6660	0.074*
H7C	0.7234	0.7094	0.7485	0.074*
C8	0.81847 (10)	0.98339 (13)	0.59471 (10)	0.0370 (3)
C9	0.90757 (11)	0.92379 (15)	0.70239 (11)	0.0415 (3)
H9	0.9070	0.9489	0.7747	0.050*
C10	0.99711 (12)	0.82801 (15)	0.70462 (11)	0.0433 (3)
H10	1.0556	0.7891	0.7778	0.052*
C11	0.99954 (11)	0.79001 (15)	0.59772 (11)	0.0435 (3)
C12	0.91149 (14)	0.84879 (19)	0.48968 (12)	0.0592 (4)
H12	0.9124	0.8242	0.4175	0.071*
C13	0.82247 (13)	0.94363 (18)	0.48875 (12)	0.0542 (4)
H13	0.7637	0.9819	0.4154	0.065*
C14	0.72117 (10)	1.08629 (13)	0.59372 (10)	0.0369 (3)
N1	0.53173 (9)	0.68267 (11)	0.46589 (8)	0.0359 (2)
H1	0.4763	0.7405	0.4674	0.043*
N2	0.40790 (11)	0.66254 (13)	0.26020 (9)	0.0482 (3)
H2A	0.3555	0.7216	0.2661	0.058*
H2B	0.3930	0.6276	0.1908	0.058*
O1	0.63458 (8)	1.12882 (11)	0.49535 (8)	0.0503 (3)
O2	0.73063 (8)	1.12516 (11)	0.69528 (8)	0.0474 (2)
O3	1.08494 (10)	0.69729 (13)	0.59355 (10)	0.0598 (3)
H3A	1.145 (2)	0.672 (2)	0.675 (2)	0.089 (6)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C2	0.0376 (6)	0.0431 (7)	0.0414 (6)	−0.0007 (5)	0.0200 (5)	0.0035 (5)
C3	0.0437 (7)	0.0584 (9)	0.0572 (8)	0.0125 (6)	0.0239 (6)	0.0110 (7)
C4	0.0607 (8)	0.0492 (8)	0.0751 (10)	0.0178 (7)	0.0453 (8)	0.0095 (7)
C5	0.0657 (8)	0.0392 (7)	0.0571 (8)	0.0039 (6)	0.0422 (7)	−0.0004 (6)
C6	0.0463 (6)	0.0351 (6)	0.0416 (6)	−0.0035 (5)	0.0269 (5)	−0.0008 (5)
C7	0.0444 (7)	0.0597 (8)	0.0395 (6)	−0.0010 (6)	0.0162 (5)	−0.0015 (6)
C8	0.0327 (5)	0.0395 (6)	0.0367 (6)	0.0008 (5)	0.0140 (5)	−0.0002 (5)
C9	0.0417 (6)	0.0474 (7)	0.0345 (6)	0.0047 (5)	0.0165 (5)	0.0002 (5)
C10	0.0390 (6)	0.0483 (7)	0.0358 (6)	0.0072 (5)	0.0110 (5)	0.0041 (5)
C11	0.0372 (6)	0.0472 (7)	0.0430 (6)	0.0062 (5)	0.0156 (5)	−0.0027 (5)
C12	0.0563 (8)	0.0815 (11)	0.0350 (6)	0.0240 (8)	0.0167 (6)	−0.0031 (7)
C13	0.0485 (7)	0.0720 (10)	0.0339 (6)	0.0205 (7)	0.0117 (5)	0.0031 (6)
C14	0.0328 (5)	0.0392 (6)	0.0391 (6)	−0.0015 (5)	0.0168 (5)	0.0015 (5)
N1	0.0373 (5)	0.0366 (5)	0.0379 (5)	0.0027 (4)	0.0208 (4)	0.0000 (4)
N2	0.0516 (6)	0.0566 (7)	0.0380 (5)	0.0035 (5)	0.0217 (5)	−0.0052 (5)
O1	0.0431 (5)	0.0630 (6)	0.0413 (5)	0.0166 (4)	0.0162 (4)	0.0076 (4)
O2	0.0415 (5)	0.0576 (6)	0.0425 (5)	0.0060 (4)	0.0188 (4)	−0.0047 (4)
O3	0.0539 (6)	0.0729 (7)	0.0498 (6)	0.0261 (5)	0.0212 (5)	0.0006 (5)

Geometric parameters (Å, º) top

C2—N1	1.3606 (15)	C8—C14	1.5013 (16)
C2—C3	1.3634 (18)	C9—C10	1.3825 (17)
C2—C7	1.4837 (18)	C9—H9	0.9300
C3—C4	1.395 (2)	C10—C11	1.3855 (17)
C3—H3	0.9300	C10—H10	0.9300
C4—C5	1.358 (2)	C11—O3	1.3546 (15)
C4—H4	0.9300	C11—C12	1.3844 (18)
C5—C6	1.4070 (17)	C12—C13	1.3775 (19)
C5—H5	0.9300	C12—H12	0.9300
C6—N2	1.3241 (16)	C13—H13	0.9300
C6—N1	1.3547 (15)	C14—O1	1.2511 (14)
C7—H7A	0.9600	C14—O2	1.2653 (14)
C7—H7B	0.9600	N1—H1	0.8600
C7—H7C	0.9600	N2—H2A	0.8600
C8—C13	1.3873 (17)	N2—H2B	0.8600
C8—C9	1.3887 (16)	O3—H3A	0.97 (2)

N1—C2—C3	119.11 (12)	C10—C9—H9	119.2
N1—C2—C7	116.13 (11)	C8—C9—H9	119.2
C3—C2—C7	124.75 (12)	C9—C10—C11	119.92 (11)
C2—C3—C4	119.27 (13)	C9—C10—H10	120.0
C2—C3—H3	120.4	C11—C10—H10	120.0
C4—C3—H3	120.4	O3—C11—C12	117.87 (12)
C5—C4—C3	120.77 (12)	O3—C11—C10	122.92 (11)
C5—C4—H4	119.6	C12—C11—C10	119.21 (12)
C3—C4—H4	119.6	C13—C12—C11	120.25 (12)
C4—C5—C6	119.91 (12)	C13—C12—H12	119.9
C4—C5—H5	120.0	C11—C12—H12	119.9
C6—C5—H5	120.0	C12—C13—C8	121.50 (12)
N2—C6—N1	118.40 (11)	C12—C13—H13	119.2
N2—C6—C5	124.19 (12)	C8—C13—H13	119.2
N1—C6—C5	117.41 (12)	O1—C14—O2	122.68 (11)
C2—C7—H7A	109.5	O1—C14—C8	120.15 (11)
C2—C7—H7B	109.5	O2—C14—C8	117.16 (10)
H7A—C7—H7B	109.5	C6—N1—C2	123.52 (10)
C2—C7—H7C	109.5	C6—N1—H1	118.2
H7A—C7—H7C	109.5	C2—N1—H1	118.2
H7B—C7—H7C	109.5	C6—N2—H2A	120.0
C13—C8—C9	117.58 (11)	C6—N2—H2B	120.0
C13—C8—C14	121.54 (11)	H2A—N2—H2B	120.0
C9—C8—C14	120.88 (11)	C11—O3—H3A	109.1 (12)
C10—C9—C8	121.54 (11)

N1—C2—C3—C4	0.1 (2)	C10—C11—C12—C13	−0.1 (3)
C7—C2—C3—C4	−179.57 (13)	C11—C12—C13—C8	0.3 (3)
C2—C3—C4—C5	0.3 (2)	C9—C8—C13—C12	−0.1 (2)
C3—C4—C5—C6	0.0 (2)	C14—C8—C13—C12	−179.76 (14)
C4—C5—C6—N2	179.79 (13)	C13—C8—C14—O1	6.19 (19)
C4—C5—C6—N1	−0.64 (19)	C9—C8—C14—O1	−173.41 (12)
C13—C8—C9—C10	−0.1 (2)	C13—C8—C14—O2	−174.60 (12)
C14—C8—C9—C10	179.48 (12)	C9—C8—C14—O2	5.80 (18)
C8—C9—C10—C11	0.3 (2)	N2—C6—N1—C2	−179.31 (11)
C9—C10—C11—O3	179.75 (13)	C5—C6—N1—C2	1.10 (17)
C9—C10—C11—C12	−0.1 (2)	C3—C2—N1—C6	−0.82 (18)
O3—C11—C12—C13	179.97 (15)	C7—C2—N1—C6	178.85 (11)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1ⁱ	0.86	2.00	2.8499 (13)	169
N2—H2A···O2ⁱ	0.86	1.94	2.7879 (14)	168
N2—H2B···O1ⁱⁱ	0.86	2.18	2.9902 (14)	157
O3—H3A···O2ⁱⁱⁱ	0.97 (2)	1.67 (2)	2.6281 (14)	168.5 (19)
C4—H4···O3^iv	0.93	2.51	3.4134 (17)	163

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

Experimental details

Crystal data
Chemical formula	C₆H₉N₂⁺·C₇H₅O₃⁻
M_r	246.26
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	11.9488 (3), 9.2952 (3), 12.4067 (3)
β (°)	117.116 (2)
V (Å³)	1226.51 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.20 × 0.18 × 0.17

Data collection
Diffractometer	Bruker SMART APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2008)
T_min, T_max	0.981, 0.984
No. of measured, independent and observed [I > 2σ(I)] reflections	11403, 3084, 2471
R_int	0.023
(sin θ/λ)_max (Å⁻¹)	0.670

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.041, 0.122, 1.04
No. of reflections	3084
No. of parameters	168
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.25, −0.20

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 1998), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1ⁱ	0.86	2.00	2.8499 (13)	169.2
N2—H2A···O2ⁱ	0.86	1.94	2.7879 (14)	167.8
N2—H2B···O1ⁱⁱ	0.86	2.18	2.9902 (14)	157.2
O3—H3A···O2ⁱⁱⁱ	0.97 (2)	1.67 (2)	2.6281 (14)	168.5 (19)
C4—H4···O3^iv	0.93	2.51	3.4134 (17)	163.3

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

Acknowledgements

VK and SB are grateful to the Department of Science and Technology (DST), New Delhi, India, for financial support through grant SR/FTP/PS-53/2007 Dt. 22–08-08.

References

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