2-Amino-5-bromo-pyridinium 3-carb-oxy-prop-2-enoate.

In the title salt, C(5)H(6)BrN(2) (+)·C(4)H(3)O(4) (-), the 2-amino-5-bromo-pyridinium cation and hydrogen maleate anion are planar, with maximum deviations from their mean planes of 0.016 (1) and 0.039 (1) Å, respectively. An intra-molecular O-H⋯O hydrogen bond generates an S(7) ring motif in the anion. In the crystal, the protonated N atom 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. The motifs are linked into a two-dimensional network parallel to (011) by N-H⋯O and C-H⋯O hydrogen bonds.

Related literature

For background to the chemistry of substituted pyridines, see: Pozharski et al. (1997 ▶); Katritzky et al. (1996 ▶). For details of n class="Chemical">maleic acid, see; Bowes et al. (2003 ▶); Jin et al. (2003 ▶); Lah & Leban (2003 ▶); Allen (2002 ▶). For bond-length data, see: Allen et al. (1987 ▶). For details of hydrogen bonding, see: Jeffrey & Saenger (1991 ▶); Jeffrey (1997 ▶); Scheiner (1997 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 ▶).

Experimental

Crystal data

C5H6BrN2 +·C4H3O4 −

M = 289.09

Triclinic,

a = 5.7434 (1) Å

b = 9.5871 (1) Å

c = 10.3034 (2) Å

α = 80.455 (1)°

β = 74.175 (1)°

γ = 85.123 (1)°

V = 537.80 (2) Å3

Z = 2

Mo Kα radiation

μ = 3.82 mm−1

T = 100 K

0.55 × 0.26 × 0.17 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T min = 0.226, T max = 0.554

17591 measured reflections

4705 independent reflections

4235 reflections with I > 2σ(I)

R int = 0.020

Refinement

R[F 2 > 2σ(F 2)] = 0.024

wR(F 2) = 0.064

S = 1.06

4705 reflections

157 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 1.11 e Å−3

Δρmin = −0.70 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/S1600536810030059/ci5141sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810030059/ci5141Isup2.hkl

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

C5H6BrN2+·C4H3O4−	Z = 2
Mr = 289.09	F(000) = 288
Triclinic, P1	Dx = 1.785 Mg m−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 5.7434 (1) Å	Cell parameters from 9953 reflections
b = 9.5871 (1) Å	θ = 2.8–35.2°
c = 10.3034 (2) Å	µ = 3.82 mm−1
α = 80.455 (1)°	T = 100 K
β = 74.175 (1)°	Plate, colourless
γ = 85.123 (1)°	0.55 × 0.26 × 0.17 mm
V = 537.80 (2) Å3

Bruker SMART APEXII CCD area-detector diffractometer	4705 independent reflections
Radiation source: fine-focus sealed tube	4235 reflections with I > 2σ(I)
graphite	Rint = 0.020
φ and ω scans	θmax = 35.0°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −9→8
Tmin = 0.226, Tmax = 0.554	k = −15→15
17591 measured reflections	l = −16→15

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)] = 0.024	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.064	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	w = 1/[σ2(Fo2) + (0.0326P)2 + 0.177P] where P = (Fo2 + 2Fc2)/3
4705 reflections	(Δ/σ)max = 0.001
157 parameters	Δρmax = 1.11 e Å−3
0 restraints	Δρmin = −0.70 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
Br1	0.08004 (2)	0.537686 (13)	0.294128 (12)	0.02696 (4)
N1	0.42643 (16)	0.83409 (10)	−0.01859 (9)	0.01624 (14)
N2	0.81699 (17)	0.85829 (11)	−0.15773 (10)	0.02185 (17)
C1	0.65936 (17)	0.78492 (11)	−0.05651 (10)	0.01673 (16)
C2	0.72501 (19)	0.65511 (12)	0.01629 (11)	0.01905 (18)
H2A	0.8842	0.6194	−0.0062	0.023*
C3	0.55552 (19)	0.58268 (11)	0.11897 (11)	0.01939 (18)
H3A	0.5979	0.4971	0.1659	0.023*
C4	0.31486 (19)	0.63883 (11)	0.15333 (11)	0.01821 (17)
C5	0.25417 (18)	0.76411 (11)	0.08418 (10)	0.01714 (16)
H5A	0.0962	0.8017	0.1069	0.021*
O1	0.81743 (14)	0.18263 (11)	0.44160 (9)	0.02726 (19)
H1O1	0.7489	0.1584	0.5288	0.041*
O2	0.68803 (15)	0.26191 (9)	0.25903 (8)	0.02102 (15)
O3	0.63826 (14)	0.09096 (10)	0.68047 (9)	0.02256 (16)
O4	0.27013 (14)	0.06052 (9)	0.82150 (8)	0.01999 (14)
C6	0.64341 (18)	0.21863 (11)	0.38215 (10)	0.01679 (16)
C7	0.38534 (18)	0.20548 (12)	0.46279 (11)	0.01807 (17)
H7A	0.2729	0.2353	0.4128	0.022*
C8	0.28808 (18)	0.15795 (12)	0.59511 (11)	0.01824 (17)
H8A	0.1197	0.1616	0.6220	0.022*
C9	0.40698 (18)	0.09990 (11)	0.70659 (10)	0.01663 (16)
H1N1	0.381 (3)	0.913 (2)	−0.0621 (19)	0.026 (4)*
H1N2	0.769 (3)	0.931 (2)	−0.2027 (19)	0.028 (4)*
H2N2	0.956 (4)	0.827 (2)	−0.183 (2)	0.038 (5)*

	U11	U22	U33	U12	U13	U23
Br1	0.02461 (6)	0.02342 (6)	0.02515 (6)	−0.00137 (4)	0.00082 (4)	0.00590 (4)
N1	0.0158 (3)	0.0172 (4)	0.0146 (3)	0.0015 (3)	−0.0040 (3)	−0.0003 (3)
N2	0.0163 (3)	0.0246 (4)	0.0203 (4)	0.0009 (3)	−0.0015 (3)	0.0024 (3)
C1	0.0153 (4)	0.0190 (4)	0.0154 (4)	0.0006 (3)	−0.0039 (3)	−0.0021 (3)
C2	0.0171 (4)	0.0184 (4)	0.0213 (4)	0.0028 (3)	−0.0059 (3)	−0.0023 (3)
C3	0.0209 (4)	0.0162 (4)	0.0206 (4)	0.0022 (3)	−0.0067 (3)	−0.0009 (3)
C4	0.0191 (4)	0.0175 (4)	0.0163 (4)	−0.0004 (3)	−0.0031 (3)	−0.0005 (3)
C5	0.0164 (4)	0.0179 (4)	0.0158 (4)	0.0006 (3)	−0.0031 (3)	−0.0015 (3)
O1	0.0143 (3)	0.0452 (5)	0.0193 (4)	−0.0035 (3)	−0.0053 (3)	0.0062 (3)
O2	0.0205 (3)	0.0239 (4)	0.0163 (3)	0.0014 (3)	−0.0039 (3)	0.0010 (3)
O3	0.0157 (3)	0.0322 (4)	0.0184 (3)	−0.0007 (3)	−0.0058 (3)	0.0021 (3)
O4	0.0193 (3)	0.0209 (4)	0.0162 (3)	0.0023 (3)	−0.0016 (3)	0.0008 (3)
C6	0.0158 (4)	0.0164 (4)	0.0172 (4)	−0.0001 (3)	−0.0041 (3)	−0.0006 (3)
C7	0.0146 (4)	0.0213 (4)	0.0178 (4)	0.0011 (3)	−0.0053 (3)	−0.0006 (3)
C8	0.0146 (4)	0.0211 (4)	0.0177 (4)	0.0009 (3)	−0.0042 (3)	−0.0002 (3)
C9	0.0171 (4)	0.0164 (4)	0.0161 (4)	0.0006 (3)	−0.0046 (3)	−0.0017 (3)

Br1—C4	1.8848 (11)	C4—C5	1.3609 (15)
N1—C1	1.3540 (13)	C5—H5A	0.93
N1—C5	1.3624 (13)	O1—C6	1.3032 (12)
N1—H1N1	0.870 (19)	O1—H1O1	0.88
N2—C1	1.3237 (14)	O2—C6	1.2301 (13)
N2—H1N2	0.842 (19)	O3—C9	1.2796 (12)
N2—H2N2	0.82 (2)	O4—C9	1.2477 (12)
C1—C2	1.4207 (15)	C6—C7	1.4929 (14)
C2—C3	1.3633 (16)	C7—C8	1.3417 (15)
C2—H2A	0.93	C7—H7A	0.93
C3—C4	1.4126 (15)	C8—C9	1.4988 (14)
C3—H3A	0.93	C8—H8A	0.93
C1—N1—C5	123.02 (9)	C3—C4—Br1	119.31 (8)
C1—N1—H1N1	119.6 (13)	C4—C5—N1	119.57 (9)
C5—N1—H1N1	117.3 (13)	C4—C5—H5A	120.2
C1—N2—H1N2	119.8 (13)	N1—C5—H5A	120.2
C1—N2—H2N2	120.2 (15)	C6—O1—H1O1	106.9
H1N2—N2—H2N2	120 (2)	O2—C6—O1	120.95 (9)
N2—C1—N1	119.76 (10)	O2—C6—C7	118.87 (9)
N2—C1—C2	122.44 (9)	O1—C6—C7	120.17 (9)
N1—C1—C2	117.79 (9)	C8—C7—C6	130.95 (9)
C3—C2—C1	120.27 (9)	C8—C7—H7A	114.5
C3—C2—H2A	119.9	C6—C7—H7A	114.5
C1—C2—H2A	119.9	C7—C8—C9	130.44 (9)
C2—C3—C4	119.36 (10)	C7—C8—H8A	114.8
C2—C3—H3A	120.3	C9—C8—H8A	114.8
C4—C3—H3A	120.3	O4—C9—O3	123.48 (10)
C5—C4—C3	119.99 (10)	O4—C9—C8	116.75 (9)
C5—C4—Br1	120.70 (8)	O3—C9—C8	119.77 (9)
C5—N1—C1—N2	179.73 (10)	Br1—C4—C5—N1	−178.99 (8)
C5—N1—C1—C2	−0.79 (15)	C1—N1—C5—C4	0.00 (16)
N2—C1—C2—C3	−179.37 (11)	O2—C6—C7—C8	177.71 (12)
N1—C1—C2—C3	1.17 (16)	O1—C6—C7—C8	−1.27 (19)
C1—C2—C3—C4	−0.77 (16)	C6—C7—C8—C9	−1.0 (2)
C2—C3—C4—C5	−0.03 (17)	C7—C8—C9—O4	−178.65 (11)
C2—C3—C4—Br1	179.39 (8)	C7—C8—C9—O3	0.33 (18)
C3—C4—C5—N1	0.43 (16)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1O1···O3	0.88	1.57	2.4380 (13)	171
N1—H1N1···O4i	0.87 (2)	1.88 (2)	2.7426 (13)	169 (2)
N2—H1N2···O3i	0.84 (2)	2.01 (2)	2.8495 (14)	174 (2)
N2—H2N2···O2ii	0.82 (2)	2.14 (2)	2.9534 (13)	176 (2)
C3—H3A···O2	0.93	2.37	3.2937 (14)	171
C5—H5A···O4iii	0.93	2.39	3.3051 (14)	167

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1O1⋯O3	0.88	1.57	2.4380 (13)	171
N1—H1N1⋯O4i	0.87 (2)	1.88 (2)	2.7426 (13)	169 (2)
N2—H1N2⋯O3i	0.84 (2)	2.01 (2)	2.8495 (14)	174 (2)
N2—H2N2⋯O2ii	0.82 (2)	2.14 (2)	2.9534 (13)	176 (2)
C3—H3A⋯O2	0.93	2.37	3.2937 (14)	171
C5—H5A⋯O4iii	0.93	2.39	3.3051 (14)	167

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