Cytosinium-hydrogen maleate-cytosine (1/1/1).

The title organic salt, C(4)H(6)N(3)O(+)·C(4)H(3)O(4) (-)·C(4)H(5)N(3)O, was synthesized from cytosine base and maleic acid. An intra-molecular O-H⋯O hydrogen bond occurs in the hydrogen maleate anion. The crystal packing is stabilized by inter-molecular N-H⋯O, N-H⋯N and C-H⋯O hydrogen bonds, giving rise to a nearly planar two-dimensional network parallel to (101).

Related literature

For background to cytosine, see: Devlin (1986 ▶); Johnson & Coghill (1925 ▶); Mahan et al. (2004 ▶). For the structure of cytosine, see: Barker & Marsh (1964 ▶) and for that of cytosine monohydrate, see: Jeffrey & Kinoshita (1963 ▶); Swamy et al. (2001 ▶). For the stuctures of inorganic cytosinium salts, see: Mandel (1977 ▶); Cherouana et al. (2003 ▶); Jaskólski (1989 ▶); Bagieu-Beucher (1990 ▶) and for those of cytosinium salts of organic acids, see: Gdaniec et al. (1989 ▶); Smith et al. (2005 ▶); Balasubramanian et al. (1996 ▶). For the hydrogen maleate anion, see: Madsen & Larsen (1998 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶).

Experimental

Crystal data

C4H6N3O+·C4H3O4 −·C4H5N3O

M = 338.29

Monoclinic,

a = 27.3226 (5) Å

b = 7.3618 (2) Å

c = 14.6742 (4) Å

β = 93.905 (1)°

V = 2944.77 (13) Å3

Z = 8

Mo Kα radiation

μ = 0.13 mm−1

T = 298 K

0.3 × 0.15 × 0.1 mm

Data collection

Nonius KappaCCD diffractometer

Absorption correction: none

3490 measured reflections

3485 independent reflections

2603 reflections with I > 2σ(I)

R int = 0.043

Refinement

R[F 2 > 2σ(F 2)] = 0.048

wR(F 2) = 0.136

S = 1.07

3485 reflections

202 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.36 e Å−3

Δρmin = −0.23 e Å−3

Data collection: KappaCCD Server Software (Nonius, 1998 ▶); cell refinement: DENZO and SCALEPACK (Otwinowski & Minor, 1997 ▶); data reduction: DENZO and SCALEPACK; program(s) used to solve structure: SIR2004 (Burla et al., 2005 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 (Farrugia, 1997 ▶) and PLATON (Spek, 2009 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809046571/dn2509sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809046571/dn2509Isup2.hkl

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

C4H6N3O+·C4H3O4−·C4H5N3O	F(000) = 1408
Mr = 338.29	Dx = 1.526 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 27.3226 (5) Å	Cell parameters from 3490 reflections
b = 7.3618 (2) Å	θ = 2.8–28.0°
c = 14.6742 (4) Å	µ = 0.13 mm−1
β = 93.905 (1)°	T = 298 K
V = 2944.77 (13) Å3	Prism, colourless
Z = 8	0.3 × 0.15 × 0.1 mm

Nonius KappaCCD diffractometer	2603 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.043
graphite	θmax = 28.0°, θmin = 2.8°
ω–θ scans	h = 0→35
3490 measured reflections	k = 0→9
3485 independent 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)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.136	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ2(Fo2) + (0.0596P)2 + 1.9669P] where P = (Fo2 + 2Fc2)/3
3485 reflections	(Δ/σ)max < 0.001
202 parameters	Δρmax = 0.36 e Å−3
0 restraints	Δρmin = −0.23 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 > 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
O7B	0.33929 (4)	1.06422 (15)	0.29275 (9)	0.0427 (3)
N1B	0.40074 (5)	0.90020 (18)	0.23748 (9)	0.0387 (3)
H1B	0.4147	0.9976	0.2199	0.046*
N3B	0.33603 (5)	0.75680 (17)	0.30317 (10)	0.0356 (3)
H3B	0.3085	0.7616	0.3281	0.043*
N8B	0.33306 (6)	0.44790 (19)	0.31458 (11)	0.0497 (4)
H8B1	0.3055	0.4591	0.3390	0.060*
H8B2	0.3452	0.3417	0.3067	0.060*
C2B	0.35779 (6)	0.9147 (2)	0.27857 (11)	0.0345 (3)
C4B	0.35667 (6)	0.5930 (2)	0.28930 (11)	0.0377 (4)
C5B	0.40201 (6)	0.5833 (2)	0.24822 (12)	0.0428 (4)
H5B	0.4171	0.4722	0.2390	0.051*
C6B	0.42225 (6)	0.7386 (2)	0.22325 (12)	0.0429 (4)
H6B	0.4518	0.7356	0.1954	0.052*
O7A	0.23768 (4)	0.47389 (15)	0.38025 (9)	0.0467 (3)
N1A	0.17582 (5)	0.63603 (19)	0.43517 (10)	0.0406 (3)
H1A	0.1605	0.5378	0.4474	0.049*
N3A	0.24320 (5)	0.78198 (17)	0.37790 (10)	0.0366 (3)
N8A	0.24807 (6)	1.09115 (19)	0.37624 (12)	0.0508 (4)
H8A1	0.2757	1.0810	0.3519	0.061*
H8A2	0.2365	1.1970	0.3873	0.061*
C2A	0.21960 (6)	0.6237 (2)	0.39693 (11)	0.0355 (3)
C4A	0.22347 (6)	0.9448 (2)	0.39665 (12)	0.0378 (4)
C5A	0.17782 (6)	0.9546 (2)	0.43695 (13)	0.0429 (4)
H5A	0.1640	1.0659	0.4506	0.051*
C6A	0.15542 (6)	0.7983 (2)	0.45467 (13)	0.0433 (4)
H6A	0.1254	0.8008	0.4808	0.052*
O1	0.00023 (4)	0.51357 (17)	0.62970 (9)	0.0448 (3)
O2	−0.05080 (5)	0.30095 (18)	0.67256 (10)	0.0541 (4)
O3	0.07419 (4)	0.53110 (16)	0.54870 (8)	0.0419 (3)
H3	0.0374 (7)	0.532 (3)	0.5856 (13)	0.063*
O4	0.12212 (5)	0.33885 (18)	0.48081 (9)	0.054
C1	0.08607 (6)	0.3706 (2)	0.52447 (11)	0.038
C2	0.05603 (7)	0.2114 (2)	0.54876 (14)	0.049
H1	0.0676	0.1001	0.5293	0.059*
C3	0.01551 (7)	0.2018 (2)	0.59356 (14)	0.0504 (5)
H2	0.0033	0.0850	0.6003	0.061*
C4	−0.01358 (6)	0.3478 (2)	0.63484 (12)	0.0402 (4)

	U11	U22	U33	U12	U13	U23
O7B	0.0443 (6)	0.0235 (6)	0.0615 (8)	0.0016 (4)	0.0113 (5)	−0.0015 (5)
N1B	0.0405 (7)	0.0322 (7)	0.0444 (8)	−0.0021 (5)	0.0104 (6)	−0.0013 (6)
N3B	0.0351 (7)	0.0245 (6)	0.0479 (8)	0.0008 (5)	0.0077 (6)	−0.0014 (5)
N8B	0.0544 (9)	0.0260 (7)	0.0704 (10)	0.0031 (6)	0.0172 (8)	0.0006 (7)
C2B	0.0369 (8)	0.0278 (8)	0.0385 (8)	0.0007 (6)	0.0013 (6)	−0.0017 (6)
C4B	0.0442 (9)	0.0267 (8)	0.0419 (9)	0.0022 (6)	0.0008 (7)	−0.0022 (6)
C5B	0.0440 (9)	0.0352 (9)	0.0500 (10)	0.0104 (7)	0.0084 (8)	−0.0028 (7)
C6B	0.0408 (9)	0.0430 (10)	0.0461 (9)	0.0061 (7)	0.0104 (7)	−0.0036 (7)
O7A	0.0452 (7)	0.0239 (6)	0.0724 (8)	0.0005 (5)	0.0135 (6)	−0.0010 (6)
N1A	0.0380 (7)	0.0313 (7)	0.0533 (8)	−0.0045 (6)	0.0099 (6)	−0.0021 (6)
N3A	0.0374 (7)	0.0215 (6)	0.0514 (8)	0.0010 (5)	0.0061 (6)	0.0001 (6)
N8A	0.0503 (8)	0.0243 (7)	0.0793 (11)	0.0016 (6)	0.0165 (8)	−0.0002 (7)
C2A	0.0361 (8)	0.0259 (8)	0.0446 (9)	0.0003 (6)	0.0029 (7)	−0.0001 (6)
C4A	0.0392 (8)	0.0277 (8)	0.0465 (9)	0.0027 (6)	0.0016 (7)	−0.0014 (7)
C5A	0.0415 (9)	0.0325 (8)	0.0550 (10)	0.0077 (7)	0.0059 (7)	−0.0060 (7)
C6A	0.0362 (8)	0.0433 (10)	0.0510 (10)	0.0031 (7)	0.0082 (7)	−0.0062 (8)
O1	0.0403 (6)	0.0392 (7)	0.0566 (7)	−0.0014 (5)	0.0154 (5)	−0.0037 (6)
O2	0.0455 (7)	0.0501 (8)	0.0694 (9)	−0.0055 (6)	0.0239 (6)	0.0023 (7)
O3	0.0418 (6)	0.0349 (6)	0.0506 (7)	−0.0033 (5)	0.0137 (5)	−0.0028 (5)
O4	0.052	0.046	0.067	0.000	0.030	−0.006
C1	0.037	0.038	0.040	−0.001	0.007	0.000
C2	0.053	0.031	0.067	0.002	0.020	−0.002
C3	0.0526 (10)	0.0309 (9)	0.0696 (12)	−0.0038 (7)	0.0179 (9)	0.0020 (8)
C4	0.0367 (8)	0.0401 (9)	0.0443 (9)	−0.0023 (7)	0.0067 (7)	0.0016 (7)

O7B—C2B	1.2348 (19)	N3A—C2A	1.3697 (19)
N1B—C6B	1.350 (2)	N8A—C4A	1.315 (2)
N1B—C2B	1.360 (2)	N8A—H8A1	0.8600
N1B—H1B	0.8600	N8A—H8A2	0.8600
N3B—C4B	1.353 (2)	C4A—C5A	1.418 (2)
N3B—C2B	1.365 (2)	C5A—C6A	1.337 (2)
N3B—H3B	0.8600	C5A—H5A	0.9300
N8B—C4B	1.314 (2)	C6A—H6A	0.9300
N8B—H8B1	0.8600	O1—C4	1.281 (2)
N8B—H8B2	0.8600	O1—H3	1.25 (2)
C4B—C5B	1.416 (2)	O2—C4	1.239 (2)
C5B—C6B	1.332 (2)	O3—C1	1.282 (2)
C5B—H5B	0.9300	O3—H3	1.17 (2)
C6B—H6B	0.9300	O4—C1	1.2333 (19)
O7A—C2A	1.2398 (19)	C1—C2	1.488 (2)
N1A—C6A	1.357 (2)	C2—C3	1.327 (3)
N1A—C2A	1.358 (2)	C2—H1	0.9300
N1A—H1A	0.8600	C3—C4	1.490 (3)
N3A—C4A	1.3503 (19)	C3—H2	0.9300
C6B—N1B—C2B	122.40 (14)	H8A1—N8A—H8A2	120.0
C6B—N1B—H1B	118.8	O7A—C2A—N1A	121.00 (14)
C2B—N1B—H1B	118.8	O7A—C2A—N3A	121.13 (14)
C4B—N3B—C2B	121.71 (13)	N1A—C2A—N3A	117.87 (13)
C4B—N3B—H3B	119.1	N8A—C4A—N3A	117.61 (15)
C2B—N3B—H3B	119.1	N8A—C4A—C5A	122.06 (15)
C4B—N8B—H8B1	120.0	N3A—C4A—C5A	120.33 (15)
C4B—N8B—H8B2	120.0	C6A—C5A—C4A	117.66 (15)
H8B1—N8B—H8B2	120.0	C6A—C5A—H5A	121.2
O7B—C2B—N1B	121.34 (14)	C4A—C5A—H5A	121.2
O7B—C2B—N3B	121.59 (14)	C5A—C6A—N1A	121.10 (15)
N1B—C2B—N3B	117.07 (13)	C5A—C6A—H6A	119.4
N8B—C4B—N3B	117.68 (15)	N1A—C6A—H6A	119.4
N8B—C4B—C5B	122.64 (15)	C4—O1—H3	112.6 (11)
N3B—C4B—C5B	119.67 (15)	C1—O3—H3	111.8 (12)
C6B—C5B—C4B	117.72 (15)	O4—C1—O3	123.04 (15)
C6B—C5B—H5B	121.1	O4—C1—C2	116.62 (16)
C4B—C5B—H5B	121.1	O3—C1—C2	120.34 (14)
C5B—C6B—N1B	121.38 (15)	C3—C2—C1	130.78 (17)
C5B—C6B—H6B	119.3	C3—C2—H1	114.6
N1B—C6B—H6B	119.3	C1—C2—H1	114.6
C6A—N1A—C2A	122.13 (14)	C2—C3—C4	130.43 (16)
C6A—N1A—H1A	118.9	C2—C3—H2	114.8
C2A—N1A—H1A	118.9	C4—C3—H2	114.8
C4A—N3A—C2A	120.90 (13)	O2—C4—O1	123.04 (16)
C4A—N8A—H8A1	120.0	O2—C4—C3	117.21 (16)
C4A—N8A—H8A2	120.0	O1—C4—C3	119.74 (14)

D—H···A	D—H	H···A	D···A	D—H···A
N1A—H1A···O4	0.86	1.89	2.7426 (19)	174
N1B—H1B···O2i	0.86	1.91	2.7701 (19)	174
N8A—H8A1···O7B	0.86	2.00	2.8582 (19)	178
N8A—H8A2···O7Aii	0.86	2.04	2.8329 (19)	153
N3B—H3B···N3A	0.86	1.98	2.8370 (19)	176
N8B—H8B1···O7A	0.86	1.99	2.8458 (19)	173
N8B—H8B2···O7Biii	0.86	2.06	2.8491 (18)	153
O3—H3···O1	1.17 (2)	1.25 (2)	2.4167 (16)	173 (2)
C6B—H6B···O1i	0.93	2.50	3.186 (2)	131
C5B—H5B···O2iv	0.93	2.42	3.330 (2)	165
C5A—H5A···O4ii	0.93	2.37	3.296 (2)	175

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1A—H1A⋯O4	0.86	1.89	2.7426 (19)	174
N1B—H1B⋯O2i	0.86	1.91	2.7701 (19)	174
N8A—H8A1⋯O7B	0.86	2.00	2.8582 (19)	178
N8A—H8A2⋯O7A ii	0.86	2.04	2.8329 (19)	153
N3B—H3B⋯N3A	0.86	1.98	2.8370 (19)	176
N8B—H8B1⋯O7A	0.86	1.99	2.8458 (19)	173
N8B—H8B2⋯O7B iii	0.86	2.06	2.8491 (18)	153
O3—H3⋯O1	1.17 (2)	1.25 (2)	2.4167 (16)	173 (2)
C6B—H6B⋯O1i	0.93	2.50	3.186 (2)	131
C5B—H5B⋯O2iv	0.93	2.42	3.330 (2)	165
C5A—H5A⋯O4ii	0.93	2.37	3.296 (2)	175

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