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

In the title mol-ecular salt, C(6)H(9)N(2) (+)·C(3)H(3)O(4) (-), the cation is essentially planar, with a maximum deviation of 0.010 (3) Å. In the anion, an intra-molecular O-H⋯O hydrogen bond generates an S(6) ring and results in a folded conformation. In the crystal, the protonated NH group 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. Weak inter-molecular C-H⋯O inter-actions help to further stabilize the crystal structure.

Related literature

For background to the chemistry of substituted pyridines, see: Pozharski et al. (1997 ▶); Katritzky et al. (1996 ▶). For related structures, see: Nahringbauer & Kvick (1977 ▶); Feng et al. (2005 ▶); Xuan et al. (2003 ▶); Jin et al. (2005 ▶); Hemamalini & Fun (2010 ▶). For details of hydrogen bonding, see: Jeffrey & Saenger (1991 ▶); Jeffrey (1997 ▶); Scheiner (1997 ▶). For the conformation of the malonate ion, see: Djinović et al. (1990 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶). For bond-length data, see: Allen et al. (1987 ▶). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 ▶).

Experimental

Crystal data

C6H9N2 +·C3H3O4 −

M = 212.21

Monoclinic,

a = 3.8082 (13) Å

b = 16.963 (5) Å

c = 15.372 (5) Å

β = 95.436 (9)°

V = 988.6 (5) Å3

Z = 4

Mo Kα radiation

μ = 0.11 mm−1

T = 100 K

0.22 × 0.21 × 0.13 mm

Data collection

Bruker APEXII DUO CCD diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T min = 0.975, T max = 0.986

8134 measured reflections

2210 independent reflections

1647 reflections with I > 2σ(I)

R int = 0.049

Refinement

R[F 2 > 2σ(F 2)] = 0.058

wR(F 2) = 0.185

S = 1.11

2210 reflections

180 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.41 e Å−3

Δρmin = −0.35 e Å−3

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; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810019239/hb5460sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810019239/hb5460Isup2.hkl

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

C6H9N2+·C3H3O4−	F(000) = 448
Mr = 212.21	Dx = 1.426 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3020 reflections
a = 3.8082 (13) Å	θ = 2.4–29.9°
b = 16.963 (5) Å	µ = 0.11 mm−1
c = 15.372 (5) Å	T = 100 K
β = 95.436 (9)°	Block, colourless
V = 988.6 (5) Å3	0.22 × 0.21 × 0.13 mm
Z = 4

Bruker APEXII DUO CCD diffractometer	2210 independent reflections
Radiation source: fine-focus sealed tube	1647 reflections with I > 2σ(I)
graphite	Rint = 0.049
φ and ω scans	θmax = 27.5°, θmin = 1.8°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −3→4
Tmin = 0.975, Tmax = 0.986	k = −22→21
8134 measured reflections	l = −19→19

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)] = 0.058	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.185	H atoms treated by a mixture of independent and constrained refinement
S = 1.11	w = 1/[σ2(Fo2) + (0.0826P)2 + 1.1878P] where P = (Fo2 + 2Fc2)/3
2210 reflections	(Δ/σ)max < 0.001
180 parameters	Δρmax = 0.41 e Å−3
0 restraints	Δρmin = −0.35 e Å−3

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 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.

	x	y	z	Uiso*/Ueq
N1	0.9416 (6)	0.73279 (11)	0.44933 (13)	0.0206 (5)
N2	1.1470 (7)	0.75544 (13)	0.31461 (14)	0.0244 (5)
C1	1.0172 (7)	0.78349 (13)	0.38551 (16)	0.0200 (5)
C2	0.9494 (7)	0.86455 (14)	0.39920 (17)	0.0227 (6)
C3	0.8223 (7)	0.88786 (13)	0.47473 (17)	0.0225 (5)
C4	0.7545 (7)	0.83392 (14)	0.54172 (16)	0.0220 (5)
C5	0.8174 (7)	0.75628 (14)	0.52501 (16)	0.0216 (5)
C6	0.6322 (9)	0.86073 (17)	0.62714 (19)	0.0287 (6)
O1	0.3293 (5)	0.58819 (10)	0.30911 (11)	0.0254 (5)
O2	0.0927 (5)	0.58087 (10)	0.43646 (11)	0.0247 (5)
O3	0.5960 (6)	0.46992 (10)	0.24783 (12)	0.0288 (5)
H1O3	0.5045	0.5236	0.2593	0.043*
O4	0.5733 (6)	0.35450 (10)	0.31494 (12)	0.0305 (5)
C7	0.2547 (7)	0.55182 (13)	0.37706 (15)	0.0201 (5)
C8	0.3717 (7)	0.46644 (13)	0.38965 (16)	0.0197 (5)
C9	0.5161 (7)	0.42551 (14)	0.31344 (16)	0.0221 (5)
H2A	1.011 (8)	0.8991 (17)	0.3559 (18)	0.019 (7)*
H3A	0.762 (10)	0.943 (2)	0.485 (2)	0.042 (9)*
H5A	0.767 (7)	0.7161 (15)	0.5656 (16)	0.011 (6)*
H6A	0.817 (10)	0.885 (2)	0.661 (2)	0.038 (9)*
H6B	0.426 (11)	0.899 (2)	0.614 (2)	0.044 (10)*
H6C	0.532 (10)	0.818 (2)	0.660 (2)	0.048 (10)*
H8A	0.559 (9)	0.4656 (18)	0.4350 (19)	0.025 (8)*
H8B	0.173 (9)	0.4314 (19)	0.411 (2)	0.033 (8)*
H1N1	1.008 (10)	0.676 (2)	0.438 (2)	0.045 (10)*
H1N2	1.209 (8)	0.7882 (19)	0.273 (2)	0.025 (8)*
H2N2	1.212 (10)	0.700 (2)	0.311 (2)	0.038 (9)*

	U11	U22	U33	U12	U13	U23
N1	0.0273 (12)	0.0096 (9)	0.0251 (10)	0.0002 (8)	0.0036 (8)	0.0015 (7)
N2	0.0371 (14)	0.0120 (10)	0.0251 (11)	0.0017 (8)	0.0072 (9)	0.0023 (8)
C1	0.0234 (14)	0.0118 (11)	0.0246 (12)	−0.0001 (9)	0.0013 (9)	0.0018 (8)
C2	0.0273 (15)	0.0105 (11)	0.0301 (13)	−0.0003 (9)	0.0019 (10)	0.0023 (9)
C3	0.0227 (14)	0.0103 (10)	0.0341 (13)	0.0007 (9)	0.0008 (10)	−0.0011 (9)
C4	0.0222 (14)	0.0165 (11)	0.0273 (12)	0.0008 (9)	0.0022 (10)	−0.0030 (9)
C5	0.0264 (14)	0.0145 (11)	0.0237 (11)	0.0001 (9)	0.0025 (10)	0.0007 (9)
C6	0.0320 (17)	0.0244 (13)	0.0302 (14)	0.0001 (11)	0.0052 (12)	−0.0058 (11)
O1	0.0387 (12)	0.0126 (8)	0.0254 (9)	0.0024 (7)	0.0061 (8)	0.0024 (7)
O2	0.0374 (12)	0.0108 (8)	0.0268 (9)	0.0044 (7)	0.0082 (8)	0.0007 (6)
O3	0.0478 (13)	0.0146 (9)	0.0255 (9)	0.0002 (8)	0.0115 (8)	−0.0007 (7)
O4	0.0496 (14)	0.0108 (8)	0.0326 (10)	0.0014 (8)	0.0112 (9)	−0.0030 (7)
C7	0.0252 (14)	0.0116 (10)	0.0232 (12)	−0.0006 (9)	0.0006 (9)	0.0002 (8)
C8	0.0264 (14)	0.0110 (10)	0.0221 (11)	0.0014 (9)	0.0040 (10)	0.0007 (8)
C9	0.0284 (15)	0.0134 (11)	0.0245 (12)	−0.0015 (9)	0.0028 (10)	−0.0028 (9)

N1—C1	1.356 (3)	C5—H5A	0.96 (3)
N1—C5	1.357 (3)	C6—H6A	0.93 (4)
N1—H1N1	1.02 (4)	C6—H6B	1.03 (4)
N2—C1	1.327 (3)	C6—H6C	0.99 (4)
N2—H1N2	0.89 (3)	O1—C7	1.268 (3)
N2—H2N2	0.97 (4)	O2—C7	1.251 (3)
C1—C2	1.419 (3)	O3—C9	1.317 (3)
C2—C3	1.358 (4)	O3—H1O3	0.9974
C2—H2A	0.93 (3)	O4—C9	1.224 (3)
C3—C4	1.419 (4)	C7—C8	1.522 (3)
C3—H3A	0.97 (4)	C8—C9	1.510 (3)
C4—C5	1.367 (3)	C8—H8A	0.95 (3)
C4—C6	1.505 (4)	C8—H8B	1.04 (4)
C1—N1—C5	123.3 (2)	C4—C5—H5A	121.0 (15)
C1—N1—H1N1	114 (2)	C4—C6—H6A	110 (2)
C5—N1—H1N1	122 (2)	C4—C6—H6B	108 (2)
C1—N2—H1N2	120 (2)	H6A—C6—H6B	110 (3)
C1—N2—H2N2	120.6 (19)	C4—C6—H6C	113 (2)
H1N2—N2—H2N2	118 (3)	H6A—C6—H6C	110 (3)
N2—C1—N1	119.2 (2)	H6B—C6—H6C	105 (3)
N2—C1—C2	123.8 (2)	C9—O3—H1O3	106.1
N1—C1—C2	117.0 (2)	O2—C7—O1	125.0 (2)
C3—C2—C1	119.6 (2)	O2—C7—C8	116.2 (2)
C3—C2—H2A	124.1 (18)	O1—C7—C8	118.8 (2)
C1—C2—H2A	116.2 (18)	C9—C8—C7	117.6 (2)
C2—C3—C4	122.4 (2)	C9—C8—H8A	105.0 (18)
C2—C3—H3A	121 (2)	C7—C8—H8A	107.3 (19)
C4—C3—H3A	116 (2)	C9—C8—H8B	107.9 (18)
C5—C4—C3	116.0 (2)	C7—C8—H8B	111.9 (19)
C5—C4—C6	122.0 (2)	H8A—C8—H8B	106 (3)
C3—C4—C6	122.1 (2)	O4—C9—O3	121.6 (2)
N1—C5—C4	121.7 (2)	O4—C9—C8	121.0 (2)
N1—C5—H5A	117.3 (15)	O3—C9—C8	117.3 (2)
C5—N1—C1—N2	178.1 (2)	C1—N1—C5—C4	0.9 (4)
C5—N1—C1—C2	−2.1 (4)	C3—C4—C5—N1	0.9 (4)
N2—C1—C2—C3	−178.8 (3)	C6—C4—C5—N1	−177.2 (2)
N1—C1—C2—C3	1.5 (4)	O2—C7—C8—C9	170.6 (2)
C1—C2—C3—C4	0.2 (4)	O1—C7—C8—C9	−10.1 (4)
C2—C3—C4—C5	−1.4 (4)	C7—C8—C9—O4	−170.7 (3)
C2—C3—C4—C6	176.7 (3)	C7—C8—C9—O3	13.0 (4)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H1O3···O1	1.00	1.53	2.475 (3)	157
N1—H1N1···O2i	1.02 (3)	1.65 (3)	2.652 (3)	170 (3)
N2—H1N2···O4ii	0.90 (3)	2.00 (3)	2.886 (3)	171 (3)
N2—H2N2···O1i	0.98 (3)	1.95 (3)	2.924 (3)	177 (3)
C2—H2A···O3ii	0.93 (3)	2.58 (3)	3.470 (3)	159 (2)
C8—H8A···O2iii	0.95 (3)	2.41 (3)	3.304 (3)	158 (3)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H1O3⋯O1	1.00	1.53	2.475 (3)	157
N1—H1N1⋯O2i	1.02 (3)	1.65 (3)	2.652 (3)	170 (3)
N2—H1N2⋯O4ii	0.90 (3)	2.00 (3)	2.886 (3)	171 (3)
N2—H2N2⋯O1i	0.98 (3)	1.95 (3)	2.924 (3)	177 (3)
C2—H2A⋯O3ii	0.93 (3)	2.58 (3)	3.470 (3)	159 (2)
C8—H8A⋯O2iii	0.95 (3)	2.41 (3)	3.304 (3)	158 (3)

Symmetry codes: (i) ; (ii) ; (iii) .