2-Amino-6-methyl-pyridinium 4-nitro-benzoate.

In the crystal structure of the title salt, C(6)H(9)N(2) (+)·C(7)H(4)NO(4) (-), the cations and anions are linked by N-H⋯O hydrogen bonds, forming chains running parallel to the b axis.

Related literature

For background to ways of decreasing of bitterness in foods and medicines, see: Suzuki et al. (2002 ▶, 2004 ▶); Hofmann (1999 ▶); Shaw et al. (1984 ▶). For bond-length data, see: Allen et al. (1987 ▶). For related structures, see: Saminathan & Sivakumar (2007a ▶,b ▶); Näther et al. (1997 ▶); In et al. (1997 ▶); Harrison et al. (2007 ▶); Soriano-García et al. (1990 ▶); You et al. (2007 ▶).

Experimental

Crystal data

C6H9N2 +·C7H4NO4 −

M = 275.26

Monoclinic,

a = 8.0487 (11) Å

b = 6.7247 (9) Å

c = 12.7467 (17) Å

β = 101.802 (7)°

V = 675.33 (16) Å3

Z = 2

Mo Kα radiation

μ = 0.10 mm−1

T = 298 K

0.20 × 0.20 × 0.18 mm

Data collection

Bruker SMART 1000 CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2001 ▶) T min = 0.980, T max = 0.982

4175 measured reflections

1591 independent reflections

1265 reflections with I > 2σ(I)

R int = 0.026

Refinement

R[F 2 > 2σ(F 2)] = 0.039

wR(F 2) = 0.105

S = 1.04

1591 reflections

191 parameters

5 restraints

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.12 e Å−3

Δρmin = −0.17 e Å−3

Data collection: SMART (Bruker, 2007 ▶); cell refinement: SAINT (Bruker, 2007 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL.

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811003539/rz2548sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536811003539/rz2548Isup2.hkl

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

C6H9N2+·C7H4NO4−	F(000) = 288
Mr = 275.26	Dx = 1.354 Mg m−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 1260 reflections
a = 8.0487 (11) Å	θ = 2.5–24.5°
b = 6.7247 (9) Å	µ = 0.10 mm−1
c = 12.7467 (17) Å	T = 298 K
β = 101.802 (7)°	Block, colourless
V = 675.33 (16) Å3	0.20 × 0.20 × 0.18 mm
Z = 2

Bruker SMART 1000 CCD area-detector diffractometer	1591 independent reflections
Radiation source: fine-focus sealed tube	1265 reflections with I > 2σ(I)
graphite	Rint = 0.026
ω scans	θmax = 27.0°, θmin = 1.6°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −10→9
Tmin = 0.980, Tmax = 0.982	k = −8→8
4175 measured reflections	l = −16→14

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)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.105	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ2(Fo2) + (0.0566P)2 + 0.0371P] where P = (Fo2 + 2Fc2)/3
1591 reflections	(Δ/σ)max = 0.001
191 parameters	Δρmax = 0.12 e Å−3
5 restraints	Δρmin = −0.17 e Å−3

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.

	x	y	z	Uiso*/Ueq
N1	0.6188 (2)	0.2067 (4)	0.26835 (16)	0.0512 (5)
N2	0.5065 (3)	0.1703 (4)	0.08960 (18)	0.0686 (7)
N3	1.1646 (3)	0.0460 (4)	0.2380 (2)	0.0627 (6)
O1	1.1579 (3)	−0.0626 (4)	0.16070 (19)	0.0851 (7)
O2	1.2502 (3)	0.0106 (4)	0.32683 (18)	0.0880 (7)
O3	0.7086 (2)	0.8232 (3)	0.09467 (14)	0.0688 (5)
O4	0.8038 (2)	0.8810 (3)	0.26794 (14)	0.0657 (5)
C1	1.0666 (3)	0.2328 (4)	0.2239 (2)	0.0516 (6)
C2	0.9742 (3)	0.2807 (4)	0.1239 (2)	0.0561 (6)
H2	0.9713	0.1955	0.0661	0.067*
C3	0.8860 (3)	0.4578 (4)	0.11130 (19)	0.0533 (6)
H3	0.8237	0.4927	0.0441	0.064*
C4	0.8890 (3)	0.5844 (4)	0.19746 (17)	0.0466 (5)
C5	0.9823 (3)	0.5302 (4)	0.29720 (19)	0.0582 (7)
H5	0.9845	0.6137	0.3556	0.070*
C6	1.0720 (3)	0.3536 (4)	0.3108 (2)	0.0583 (7)
H6	1.1348	0.3177	0.3777	0.070*
C7	0.7922 (3)	0.7779 (4)	0.1853 (2)	0.0514 (6)
C8	0.6412 (3)	0.3019 (5)	0.3640 (2)	0.0608 (7)
C9	0.5624 (4)	0.4787 (5)	0.3702 (3)	0.0767 (9)
H9	0.5770	0.5468	0.4350	0.092*
C10	0.4597 (4)	0.5562 (5)	0.2784 (3)	0.0770 (9)
H10	0.4059	0.6775	0.2823	0.092*
C11	0.4361 (3)	0.4599 (5)	0.1837 (3)	0.0656 (8)
H11	0.3662	0.5135	0.1231	0.079*
C12	0.5192 (3)	0.2767 (4)	0.1779 (2)	0.0542 (6)
C13	0.7530 (4)	0.2001 (7)	0.4557 (2)	0.0845 (10)
H13A	0.7053	0.0731	0.4672	0.127*
H13B	0.7622	0.2801	0.5190	0.127*
H13C	0.8636	0.1816	0.4399	0.127*
H1	0.676 (4)	0.092 (3)	0.264 (2)	0.080*
H2A	0.440 (3)	0.204 (5)	0.0282 (13)	0.080*
H2B	0.571 (3)	0.064 (3)	0.088 (2)	0.080*

	U11	U22	U33	U12	U13	U23
N1	0.0508 (11)	0.0513 (13)	0.0501 (10)	0.0044 (10)	0.0069 (8)	0.0074 (10)
N2	0.0733 (15)	0.0610 (16)	0.0586 (13)	0.0073 (13)	−0.0163 (11)	0.0064 (13)
N3	0.0631 (13)	0.0528 (15)	0.0738 (15)	0.0060 (11)	0.0178 (11)	0.0139 (13)
O1	0.1048 (16)	0.0672 (14)	0.0887 (15)	0.0245 (13)	0.0325 (13)	0.0011 (13)
O2	0.0926 (15)	0.0715 (16)	0.0917 (14)	0.0277 (13)	−0.0003 (12)	0.0160 (13)
O3	0.0837 (12)	0.0484 (11)	0.0595 (10)	0.0035 (10)	−0.0198 (8)	0.0002 (9)
O4	0.0827 (12)	0.0477 (11)	0.0568 (10)	0.0119 (10)	−0.0088 (9)	−0.0042 (9)
C1	0.0492 (12)	0.0439 (14)	0.0621 (14)	−0.0003 (10)	0.0125 (10)	0.0091 (12)
C2	0.0641 (14)	0.0527 (16)	0.0516 (13)	0.0013 (13)	0.0118 (11)	−0.0010 (12)
C3	0.0603 (14)	0.0508 (15)	0.0449 (12)	−0.0013 (12)	0.0019 (11)	0.0042 (12)
C4	0.0483 (12)	0.0389 (12)	0.0485 (12)	−0.0047 (10)	0.0001 (9)	0.0038 (10)
C5	0.0675 (16)	0.0501 (15)	0.0502 (13)	0.0024 (13)	−0.0042 (11)	−0.0028 (13)
C6	0.0625 (15)	0.0531 (17)	0.0531 (13)	0.0044 (12)	−0.0027 (11)	0.0072 (12)
C7	0.0535 (12)	0.0394 (13)	0.0539 (13)	−0.0048 (11)	−0.0062 (10)	0.0004 (12)
C8	0.0603 (14)	0.0689 (17)	0.0555 (14)	0.0064 (14)	0.0173 (11)	0.0015 (14)
C9	0.079 (2)	0.078 (2)	0.0775 (19)	0.0153 (18)	0.0268 (16)	−0.0056 (18)
C10	0.0680 (17)	0.066 (2)	0.102 (2)	0.0169 (16)	0.0304 (16)	0.004 (2)
C11	0.0519 (14)	0.0621 (18)	0.0810 (19)	0.0102 (13)	0.0097 (13)	0.0150 (16)
C12	0.0457 (12)	0.0548 (16)	0.0589 (14)	−0.0025 (11)	0.0033 (10)	0.0115 (13)
C13	0.099 (2)	0.102 (3)	0.0512 (15)	0.022 (2)	0.0107 (14)	0.0011 (18)

N1—C12	1.348 (3)	C4—C5	1.386 (3)
N1—C8	1.356 (3)	C4—C7	1.508 (3)
N1—H1	0.908 (10)	C5—C6	1.382 (4)
N2—C12	1.320 (4)	C5—H5	0.9300
N2—H2A	0.883 (10)	C6—H6	0.9300
N2—H2B	0.889 (10)	C8—C9	1.357 (4)
N3—O1	1.218 (3)	C8—C13	1.488 (4)
N3—O2	1.223 (3)	C9—C10	1.389 (4)
N3—C1	1.475 (3)	C9—H9	0.9300
O3—C7	1.250 (3)	C10—C11	1.349 (4)
O4—C7	1.249 (3)	C10—H10	0.9300
C1—C6	1.368 (4)	C11—C12	1.411 (4)
C1—C2	1.376 (3)	C11—H11	0.9300
C2—C3	1.379 (4)	C13—H13A	0.9600
C2—H2	0.9300	C13—H13B	0.9600
C3—C4	1.386 (3)	C13—H13C	0.9600
C3—H3	0.9300
C12—N1—C8	123.4 (2)	C5—C6—H6	120.7
C12—N1—H1	117.8 (19)	O4—C7—O3	125.3 (2)
C8—N1—H1	118.7 (19)	O4—C7—C4	116.4 (2)
C12—N2—H2A	122.9 (19)	O3—C7—C4	118.3 (2)
C12—N2—H2B	121.1 (18)	N1—C8—C9	119.2 (3)
H2A—N2—H2B	116 (2)	N1—C8—C13	115.9 (3)
O1—N3—O2	123.8 (2)	C9—C8—C13	124.9 (3)
O1—N3—C1	118.5 (2)	C8—C9—C10	118.9 (3)
O2—N3—C1	117.7 (2)	C8—C9—H9	120.5
C6—C1—C2	122.2 (2)	C10—C9—H9	120.5
C6—C1—N3	118.7 (2)	C11—C10—C9	121.7 (3)
C2—C1—N3	119.1 (2)	C11—C10—H10	119.2
C1—C2—C3	118.5 (2)	C9—C10—H10	119.2
C1—C2—H2	120.7	C10—C11—C12	119.0 (3)
C3—C2—H2	120.7	C10—C11—H11	120.5
C2—C3—C4	120.9 (2)	C12—C11—H11	120.5
C2—C3—H3	119.6	N2—C12—N1	118.0 (2)
C4—C3—H3	119.6	N2—C12—C11	124.3 (2)
C3—C4—C5	118.9 (2)	N1—C12—C11	117.7 (3)
C3—C4—C7	121.6 (2)	C8—C13—H13A	109.5
C5—C4—C7	119.5 (2)	C8—C13—H13B	109.5
C6—C5—C4	120.8 (2)	H13A—C13—H13B	109.5
C6—C5—H5	119.6	C8—C13—H13C	109.5
C4—C5—H5	119.6	H13A—C13—H13C	109.5
C1—C6—C5	118.6 (2)	H13B—C13—H13C	109.5
C1—C6—H6	120.7

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O4i	0.91 (2)	1.75 (3)	2.649 (3)	173 (2)
N2—H2A···O3ii	0.89 (2)	1.94 (2)	2.812 (3)	170.(2)
N2—H2B···O3i	0.89 (2)	1.95 (2)	2.838 (3)	176 (2)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O4i	0.91 (2)	1.75 (3)	2.649 (3)	173 (2)
N2—H2A⋯O3ii	0.89 (2)	1.94 (2)	2.812 (3)	170 (2)
N2—H2B⋯O3i	0.89 (2)	1.95 (2)	2.838 (3)	176 (2)

Symmetry codes: (i) ; (ii) .