2-Amino-5-methyl-pyridinium 2-carb-oxy-benzoate.

In the title salt, C(6)H(9)N(2) (+)·C(8)H(5)O(4) (-), the hydrogen phthalate anion is essentially planar, with a maximum deviation of 0.011 (2) Å. In the crystal structure, the protonated N atom of the pyridine ring and the 2-amino group of the cation are hydrogen bonded to the carboxyl-ate O atoms of the anion via a pair of N-H⋯O hydrogen bonds, forming an R(2) (2)(8) ring motif. In the hydrogen phthalate anion, there is a very strong, almost symmetric, intra-molecular O-H⋯O hydrogen bond, generating an S(7) motif [O⋯O = 2.382 (3) Å]. Furthermore, these two molecular motif rings are connected by a bifurcated N-H⋯(O,O) hydrogen-bonded motif R(1) (2)(4), forming a supra-molecular ribbon along the b axis. The crystal structure is further stabilized by π-π inter-actions between the cations and anions [centroid-centroid distance = 3.6999 (10) Å].

Related literature

For the crystal structure of phthalic acid, see: Nowacki & Jaggi (1957 ▶); Küppers (1981 ▶); Ermer (1981 ▶). For the crystal structures of hydrogen phthalates, see: Jessen (1990 ▶); Jin et al. (2003 ▶); Küppers (1978 ▶). For a description of the Cambridge Structural Database, see: Allen (2002 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶). For reference bond-length data, see: Allen et al. (1987 ▶).

Experimental

Crystal data

C6H9N2 +·C8H5O4 −

M = 274.27

Monoclinic,

a = 11.3853 (2) Å

b = 8.8203 (2) Å

c = 13.4617 (3) Å

β = 101.540 (2)°

V = 1324.52 (5) Å3

Z = 4

Mo Kα radiation

μ = 0.10 mm−1

T = 296 K

0.47 × 0.33 × 0.20 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T min = 0.953, T max = 0.980

12332 measured reflections

3049 independent reflections

2054 reflections with I > 2σ(I)

R int = 0.028

Refinement

R[F 2 > 2σ(F 2)] = 0.049

wR(F 2) = 0.136

S = 1.03

3049 reflections

197 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.19 e Å−3

Δρmin = −0.14 e Å−3

Data collection: APEX2 (Bruker, 2009 ▶); cell refinement: SAINT (Bruker, 2009 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053681003000X/wn2402sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053681003000X/wn2402Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C6H9N2+·C8H5O4−	F(000) = 576
Mr = 274.27	Dx = 1.375 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 3124 reflections
a = 11.3853 (2) Å	θ = 2.6–28.6°
b = 8.8203 (2) Å	µ = 0.10 mm−1
c = 13.4617 (3) Å	T = 296 K
β = 101.540 (2)°	Block, colourless
V = 1324.52 (5) Å3	0.47 × 0.33 × 0.20 mm
Z = 4

Bruker SMART APEXII CCD area-detector diffractometer	3049 independent reflections
Radiation source: fine-focus sealed tube	2054 reflections with I > 2σ(I)
graphite	Rint = 0.028
φ and ω scans	θmax = 27.5°, θmin = 2.6°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −14→14
Tmin = 0.953, Tmax = 0.980	k = −11→11
12332 measured reflections	l = −17→12

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)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.136	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ2(Fo2) + (0.0585P)2 + 0.230P] where P = (Fo2 + 2Fc2)/3
3049 reflections	(Δ/σ)max < 0.001
197 parameters	Δρmax = 0.19 e Å−3
0 restraints	Δρmin = −0.14 e Å−3

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.

	x	y	z	Uiso*/Ueq
O1	0.22365 (18)	−0.0844 (2)	0.56803 (13)	0.1122 (6)
O2	0.11271 (15)	−0.09799 (18)	0.41687 (11)	0.0907 (5)
O3	0.39091 (17)	0.0516 (2)	0.66089 (11)	0.1042 (6)
O4	0.51382 (17)	0.2270 (2)	0.63733 (13)	0.1129 (6)
C1	0.24378 (17)	0.09471 (19)	0.33146 (12)	0.0560 (4)
H1A	0.1762	0.0456	0.2956	0.067*
C2	0.30478 (17)	0.1928 (2)	0.28048 (13)	0.0609 (5)
H2A	0.2777	0.2107	0.2116	0.073*
C3	0.40493 (17)	0.2635 (2)	0.33145 (15)	0.0689 (5)
H3A	0.4481	0.3277	0.2973	0.083*
C4	0.44221 (17)	0.2395 (2)	0.43406 (16)	0.0675 (5)
H4A	0.5104	0.2894	0.4682	0.081*
C5	0.38123 (16)	0.14284 (19)	0.48854 (12)	0.0547 (4)
C6	0.27973 (15)	0.06614 (17)	0.43513 (12)	0.0508 (4)
C7	0.4338 (2)	0.1418 (3)	0.60205 (16)	0.0719 (6)
C8	0.1997 (2)	−0.0461 (2)	0.47582 (15)	0.0644 (5)
N1	0.55034 (14)	0.21351 (16)	0.02651 (10)	0.0539 (4)
N2	0.46340 (18)	0.2514 (2)	−0.14144 (14)	0.0712 (5)
C9	0.54553 (16)	0.18327 (18)	−0.07217 (12)	0.0532 (4)
C10	0.62974 (17)	0.0798 (2)	−0.09620 (14)	0.0611 (5)
H10A	0.6290	0.0552	−0.1635	0.073*
C11	0.71156 (17)	0.0164 (2)	−0.02130 (14)	0.0619 (5)
H11A	0.7671	−0.0511	−0.0383	0.074*
C12	0.71554 (16)	0.04912 (19)	0.08173 (13)	0.0573 (4)
C13	0.63244 (16)	0.14845 (19)	0.10155 (13)	0.0581 (4)
H13A	0.6316	0.1729	0.1686	0.070*
C14	0.80669 (19)	−0.0225 (3)	0.16415 (16)	0.0798 (6)
H14A	0.7953	0.0133	0.2289	0.120*
H14B	0.8858	0.0039	0.1553	0.120*
H14C	0.7975	−0.1307	0.1611	0.120*
H1N1	0.4931 (17)	0.279 (2)	0.0425 (14)	0.067 (6)*
H2N2	0.404 (2)	0.312 (3)	−0.1211 (17)	0.086 (7)*
H1N2	0.466 (2)	0.227 (3)	−0.206 (2)	0.096 (8)*
H1O1	0.308 (2)	−0.022 (3)	0.6119 (18)	0.100 (7)*

	U11	U22	U33	U12	U13	U23
O1	0.1250 (15)	0.1378 (15)	0.0725 (10)	−0.0338 (12)	0.0163 (10)	0.0395 (10)
O2	0.1126 (12)	0.0943 (11)	0.0705 (9)	−0.0427 (9)	0.0308 (9)	−0.0029 (8)
O3	0.1091 (13)	0.1526 (16)	0.0486 (8)	0.0056 (12)	0.0099 (9)	0.0157 (10)
O4	0.1112 (14)	0.1306 (15)	0.0794 (11)	−0.0074 (12)	−0.0228 (10)	−0.0167 (10)
C1	0.0660 (11)	0.0552 (9)	0.0472 (9)	−0.0033 (8)	0.0125 (8)	−0.0049 (7)
C2	0.0717 (12)	0.0679 (11)	0.0459 (9)	0.0020 (9)	0.0182 (8)	0.0024 (8)
C3	0.0639 (12)	0.0761 (12)	0.0709 (12)	−0.0040 (10)	0.0236 (10)	0.0115 (10)
C4	0.0502 (10)	0.0771 (12)	0.0731 (13)	−0.0024 (9)	0.0072 (9)	−0.0031 (10)
C5	0.0560 (10)	0.0579 (9)	0.0500 (9)	0.0147 (8)	0.0100 (8)	−0.0032 (7)
C6	0.0617 (10)	0.0460 (8)	0.0478 (9)	0.0080 (7)	0.0185 (8)	−0.0019 (7)
C7	0.0707 (13)	0.0821 (14)	0.0587 (11)	0.0237 (11)	0.0026 (10)	−0.0087 (10)
C8	0.0841 (14)	0.0567 (10)	0.0575 (11)	−0.0010 (9)	0.0265 (10)	0.0015 (8)
N1	0.0587 (9)	0.0533 (8)	0.0517 (8)	0.0012 (7)	0.0158 (7)	−0.0046 (6)
N2	0.0868 (13)	0.0727 (11)	0.0517 (10)	0.0110 (9)	0.0079 (9)	−0.0033 (8)
C9	0.0635 (11)	0.0470 (8)	0.0502 (9)	−0.0094 (8)	0.0140 (8)	−0.0026 (7)
C10	0.0753 (12)	0.0588 (10)	0.0532 (10)	−0.0047 (9)	0.0225 (9)	−0.0102 (8)
C11	0.0617 (11)	0.0564 (10)	0.0710 (11)	0.0005 (8)	0.0216 (9)	−0.0101 (9)
C12	0.0543 (10)	0.0569 (9)	0.0613 (10)	−0.0037 (8)	0.0133 (8)	−0.0035 (8)
C13	0.0642 (11)	0.0639 (10)	0.0468 (9)	−0.0019 (9)	0.0124 (8)	−0.0036 (8)
C14	0.0699 (13)	0.0880 (14)	0.0781 (13)	0.0120 (11)	0.0064 (11)	−0.0013 (11)

O1—C8	1.263 (2)	N1—C9	1.345 (2)
O1—H1O1	1.16 (3)	N1—C13	1.359 (2)
O2—C8	1.227 (2)	N1—H1N1	0.93 (2)
O3—C7	1.286 (3)	N2—C9	1.325 (2)
O3—H1O1	1.22 (3)	N2—H2N2	0.95 (2)
O4—C7	1.203 (3)	N2—H1N2	0.90 (3)
C1—C2	1.376 (2)	C9—C10	1.407 (3)
C1—C6	1.396 (2)	C10—C11	1.350 (3)
C1—H1A	0.9300	C10—H10A	0.9300
C2—C3	1.359 (3)	C11—C12	1.409 (2)
C2—H2A	0.9300	C11—H11A	0.9300
C3—C4	1.378 (3)	C12—C13	1.355 (2)
C3—H3A	0.9300	C12—C14	1.499 (3)
C4—C5	1.397 (3)	C13—H13A	0.9300
C4—H4A	0.9300	C14—H14A	0.9600
C5—C6	1.406 (2)	C14—H14B	0.9600
C5—C7	1.525 (3)	C14—H14C	0.9600
C6—C8	1.520 (3)
C8—O1—H1O1	111.6 (12)	C9—N1—H1N1	117.5 (11)
C7—O3—H1O1	110.1 (11)	C13—N1—H1N1	120.1 (11)
C2—C1—C6	122.40 (17)	C9—N2—H2N2	119.9 (13)
C2—C1—H1A	118.8	C9—N2—H1N2	114.5 (15)
C6—C1—H1A	118.8	H2N2—N2—H1N2	125 (2)
C3—C2—C1	119.53 (17)	N2—C9—N1	119.25 (17)
C3—C2—H2A	120.2	N2—C9—C10	123.33 (17)
C1—C2—H2A	120.2	N1—C9—C10	117.42 (16)
C2—C3—C4	119.66 (18)	C11—C10—C9	119.81 (16)
C2—C3—H3A	120.2	C11—C10—H10A	120.1
C4—C3—H3A	120.2	C9—C10—H10A	120.1
C3—C4—C5	122.31 (18)	C10—C11—C12	122.15 (17)
C3—C4—H4A	118.8	C10—C11—H11A	118.9
C5—C4—H4A	118.8	C12—C11—H11A	118.9
C4—C5—C6	117.98 (16)	C13—C12—C11	116.12 (16)
C4—C5—C7	113.14 (18)	C13—C12—C14	122.30 (17)
C6—C5—C7	128.82 (17)	C11—C12—C14	121.58 (17)
C1—C6—C5	118.08 (16)	C12—C13—N1	122.04 (16)
C1—C6—C8	113.62 (16)	C12—C13—H13A	119.0
C5—C6—C8	128.29 (16)	N1—C13—H13A	119.0
O4—C7—O3	119.6 (2)	C12—C14—H14A	109.5
O4—C7—C5	120.4 (2)	C12—C14—H14B	109.5
O3—C7—C5	120.0 (2)	H14A—C14—H14B	109.5
O2—C8—O1	121.58 (19)	C12—C14—H14C	109.5
O2—C8—C6	118.33 (16)	H14A—C14—H14C	109.5
O1—C8—C6	120.09 (19)	H14B—C14—H14C	109.5
C9—N1—C13	122.45 (16)
C6—C1—C2—C3	1.1 (3)	C1—C6—C8—O2	−1.1 (2)
C1—C2—C3—C4	−1.9 (3)	C5—C6—C8—O2	178.03 (17)
C2—C3—C4—C5	0.7 (3)	C1—C6—C8—O1	178.51 (19)
C3—C4—C5—C6	1.2 (3)	C5—C6—C8—O1	−2.3 (3)
C3—C4—C5—C7	−176.18 (17)	C13—N1—C9—N2	−179.69 (16)
C2—C1—C6—C5	0.8 (3)	C13—N1—C9—C10	0.1 (2)
C2—C1—C6—C8	−179.89 (16)	N2—C9—C10—C11	179.23 (17)
C4—C5—C6—C1	−1.9 (2)	N1—C9—C10—C11	−0.5 (3)
C7—C5—C6—C1	175.00 (16)	C9—C10—C11—C12	0.6 (3)
C4—C5—C6—C8	178.91 (16)	C10—C11—C12—C13	−0.1 (3)
C7—C5—C6—C8	−4.1 (3)	C10—C11—C12—C14	179.80 (18)
C4—C5—C7—O4	5.3 (3)	C11—C12—C13—N1	−0.3 (3)
C6—C5—C7—O4	−171.79 (19)	C14—C12—C13—N1	179.74 (17)
C4—C5—C7—O3	−176.07 (19)	C9—N1—C13—C12	0.4 (3)
C6—C5—C7—O3	6.9 (3)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N1···O2i	0.928 (19)	1.786 (19)	2.713 (2)	175.7 (17)
N2—H2N2···O1i	0.95 (2)	1.97 (2)	2.907 (3)	173 (2)
N2—H1N2···O3ii	0.90 (3)	2.39 (3)	3.161 (2)	143 (2)
N2—H1N2···O4ii	0.90 (3)	2.28 (3)	3.151 (3)	162 (2)
O1—H1O1···O3	1.16 (2)	1.22 (2)	2.382 (3)	175 (2)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1N1⋯O2i	0.928 (19)	1.786 (19)	2.713 (2)	175.7 (17)
N2—H2N2⋯O1i	0.95 (2)	1.97 (2)	2.907 (3)	173 (2)
N2—H1N2⋯O3ii	0.90 (3)	2.39 (3)	3.161 (2)	143 (2)
N2—H1N2⋯O4ii	0.90 (3)	2.28 (3)	3.151 (3)	162 (2)
O1—H1O1⋯O3	1.16 (2)	1.22 (2)	2.382 (3)	175 (2)

Symmetry codes: (i) ; (ii) .