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Acta Cryst. (2008). E64, o1082-o1083    [ doi:10.1107/S1600536808014244 ]

N,N',N''-Triphenylguanidinium 5-nitro-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-1-ide

P. S. Pereira Silva, S. R. Domingos, M. Ramos Silva, J. A. Paixão and A. Matos Beja

Abstract top

In the title compound, C19H18N3+.C4H2N3O4-, the dihedral angles between the phenyl rings and the plane defined by the central guanidinium fragment are in the range 41.3 (1)-66.6 (1)°. The pyrimidine ring of the anion is distorted towards a boat conformation and the nitro group is rotated 11.4 (2)° out of the uracil plane. Hydrogen bonds assemble the ions in infinite helical chains along the b axis.

Comment top

5-Nitrouracil is currently of prime interest to the non-linear optical community (Puccetti et al., 1993; Youping et al., 1992) and is also of relevance to the biological and pharmaceutical sciences (Rao et al., 1995; Pettier & Byrn, 1982).

Much of the interest in guanidine compounds and its derivatives is due to their biological activity, in particular their neuroleptic and antipsychotic properties (Weber et al., 1986; Largent et al., 1987). Our interest is focused on the physical properties of guanidine compounds, which are regarded as potentially interesting for non-linear optics applications (Zyss et al., 1993). We are currently engaged in a research project aimed at investigating the structural, dielectric and optical properties of triphenylguanidine compounds.

Compound (I) (Fig.1) is built up from triphenylguanidinium cations and 5-nitrouracilate anions. The pyrimidine ring is almost planar with a slight distortion towards a boat configuration. The nitro group is rotated 11.4 (2)° out of the plane of the uracil fragment. The central guanidine fragment of the cation of the title salt is planar with bond lengths and angles close to those expected for a central Csp2 atom, accounting for some charge delocalization between the three C—N bonds. The bond lengths C7—N6 [1.333 (2) Å], C7—N7 [1.330 (2) Å] and C7—N8 [1.337 (2) Å] are comparable with literature averages for substituted and unsubstituted guanidinium cations (1.321 and 1.328 Å, respectively; Allen et al., 1987)

The dihedral angles between the ring planes and the plane defined by the central guanidinium fragment are 41.3 (1)(C8—C13), 57.5 (1)(C14—C19) and 66.6 (1)° (C20—C25). The corresponding angles for other triphenylguanidinium salts reported in the literature are within the range 32.6 (3)–70.2 (3)° (Kemme et al., 1988; Klement et al., 1995; Pereira Silva et al., 2006, 2007a, 2007b, Pereira Silva, Cardoso et al.,(2007).

The anions and cations are linked into infinite helical chains running parallel to the b axis, via hydrogen bonds involving all the NH groups of the guanidinium fragment, the carbonyl O atoms and the deprotonated N atom of the anion (Fig. 2, Table 2). Atoms O2 and N1 accept each one H atom across a crystallographic centre of symmetry, while the O4 atom accept one hydrogen from the N8 atom related by a twofold screw axis.

Related literature top

For the non-linear optical properties of 5-nitrouracil, see: Puccetti et al. (1993), Youping et al. (1992). For reports of other triphenylguanidine salts, see: Pereira Silva et al. (2006, 2007a,b), Pereira Silva, Cardoso et al. (2007). For related literature, see: Allen et al. (1987); Kemme et al. (1988); Klement et al. (1995); Largent et al. (1987); Pettier & Byrn (1982); Rao et al. (1995); Weber et al. (1986); Zyss et al. (1993).

Experimental top

The title compound was prepared by adding 5-nitrouracil (Aldrich, 98%, 1 mmol) to triphenylguanidine (TCI 97%, 1 mmol) in a ethanol solution (80 ml). The solution was slowly warmed and then left to evaporate under ambient conditions. After a few days, small yellow transparent single crystals were deposited.

Refinement top

All H atoms were located in a difference Fourier synthesis, placed at calculated positions and refined as riding on their parent atoms, using SHELXL97 (Sheldrick, 2008) defaults [C—H = 0.93 Å, N—H = 0.86 Å and Uiso(H) = 1.2Ueq(C,N)].

Computing details top

Data collection: SMART (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. ORTEPII (Spek,2003) plot of the title compound. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. Packing diagram, viewed down the c axis, with the hydrogen bonds depicted as dashed lines. The phenyl rings have been omitted for clarity.
N,N',N''-Triphenylguanidinium 5-nitro-2,4-dioxo-1,2,3,4-tetrahydropyrimidin-1-ide top
Crystal data top
C19H18N3+·C4H2N3O4–F000 = 928
Mr = 444.45Dx = 1.348 Mg m−3
Monoclinic, P21/cMo Kα radiation
λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 5110 reflections
a = 10.7495 (4) Åθ = 2.3–21.6º
b = 15.6892 (7) ŵ = 0.10 mm−1
c = 15.5624 (7) ÅT = 293 (2) K
β = 123.456 (3)ºBlock, yellow
V = 2189.74 (18) Å30.34 × 0.20 × 0.12 mm
Z = 4
Data collection top
Bruker APEX2 CCD area-detector
diffractometer		5534 independent reflections
Radiation source: fine-focus sealed tube2650 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.086
T = 293(2) Kθmax = 28.6º
φ and ω scansθmin = 2.0º
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		h = −14→14
Tmin = 0.822, Tmax = 0.989k = −20→21
47807 measured reflectionsl = −20→20
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.050  w = 1/[σ2(Fo2) + (0.0713P)2 + 0.1061P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.154(Δ/σ)max < 0.001
S = 0.99Δρmax = 0.22 e Å−3
5534 reflectionsΔρmin = −0.17 e Å−3
299 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0068 (11)
Secondary atom site location: difference Fourier map
Crystal data top
C19H18N3+·C4H2N3O4–V = 2189.74 (18) Å3
Mr = 444.45Z = 4
Monoclinic, P21/cMo Kα
a = 10.7495 (4) ŵ = 0.10 mm−1
b = 15.6892 (7) ÅT = 293 (2) K
c = 15.5624 (7) Å0.34 × 0.20 × 0.12 mm
β = 123.456 (3)º
Data collection top
Bruker APEX2 CCD area-detector
diffractometer		5534 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)		2650 reflections with I > 2σ(I)
Tmin = 0.822, Tmax = 0.989Rint = 0.086
47807 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.050299 parameters
wR(F2) = 0.154H-atom parameters constrained
S = 0.99Δρmax = 0.22 e Å−3
5534 reflectionsΔρmin = −0.17 e Å−3
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O20.82985 (16)−0.17695 (11)0.60642 (13)0.0729 (5)
O40.61600 (16)0.07278 (11)0.59408 (15)0.0968 (6)
O70.7653 (2)0.21285 (11)0.59093 (15)0.0949 (6)
O80.9257 (2)0.19450 (12)0.55194 (16)0.0940 (6)
N10.93683 (17)−0.06007 (12)0.58600 (13)0.0581 (5)
N30.72353 (18)−0.04940 (13)0.59167 (16)0.0759 (6)
H30.6532−0.07610.59110.091*
N50.8406 (2)0.16564 (13)0.57455 (13)0.0658 (5)
C20.8316 (2)−0.09943 (17)0.59504 (16)0.0596 (6)
C40.7147 (2)0.03782 (16)0.58914 (17)0.0668 (6)
C50.8282 (2)0.07584 (14)0.57999 (14)0.0555 (5)
C60.9311 (2)0.02398 (15)0.57896 (15)0.0585 (6)
H61.00300.05060.57270.070*
N60.93433 (16)0.28871 (10)0.33661 (12)0.0538 (4)
H6A1.00860.25450.35900.065*
N70.79767 (16)0.16933 (10)0.31325 (12)0.0503 (4)
H70.87420.14680.36670.060*
N80.67626 (16)0.29829 (10)0.24472 (12)0.0491 (4)
H80.67590.34110.21010.059*
C70.80155 (19)0.25245 (12)0.29824 (14)0.0464 (5)
C80.9677 (2)0.37724 (13)0.34492 (14)0.0539 (5)
C90.8938 (3)0.43773 (15)0.3642 (2)0.0768 (7)
H90.81840.42180.37320.092*
C100.9323 (4)0.52263 (18)0.3700 (2)0.1001 (10)
H100.88060.56390.38110.120*
C111.0463 (4)0.5467 (2)0.3594 (2)0.1051 (12)
H111.07180.60380.36320.126*
C121.1207 (3)0.4857 (2)0.3434 (2)0.0959 (10)
H121.19900.50150.33740.115*
C131.0833 (2)0.40133 (17)0.33588 (16)0.0702 (7)
H131.13560.36050.32470.084*
C140.67503 (19)0.11513 (11)0.24655 (15)0.0468 (5)
C150.6368 (3)0.05200 (14)0.28837 (19)0.0765 (7)
H150.68960.04520.35940.092*
C160.5197 (4)−0.00143 (18)0.2246 (2)0.1072 (11)
H160.4934−0.04460.25260.129*
C170.4422 (3)0.00873 (17)0.1204 (2)0.0877 (8)
H170.3628−0.02730.07760.105*
C180.4805 (2)0.07121 (15)0.07889 (18)0.0666 (6)
H180.42690.07810.00780.080*
C190.5977 (2)0.12417 (13)0.14139 (15)0.0535 (5)
H190.62500.16620.11270.064*
C200.54307 (19)0.28099 (11)0.24114 (14)0.0459 (5)
C210.5506 (2)0.26333 (14)0.33038 (16)0.0584 (5)
H210.64230.26160.39310.070*
C220.4205 (3)0.24817 (15)0.3260 (2)0.0725 (6)
H220.42440.23560.38580.087*
C230.2860 (3)0.25168 (17)0.2335 (2)0.0795 (7)
H230.19880.24110.23080.095*
C240.2785 (2)0.27057 (17)0.1450 (2)0.0760 (7)
H240.18640.27350.08260.091*
C250.4079 (2)0.28527 (14)0.14842 (16)0.0605 (6)
H250.40350.29800.08840.073*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O20.0549 (9)0.0732 (11)0.0938 (12)0.0013 (8)0.0430 (8)−0.0117 (9)
O40.0486 (9)0.0987 (13)0.1444 (16)−0.0064 (8)0.0541 (10)−0.0593 (12)
O70.1289 (16)0.0814 (12)0.1126 (14)0.0391 (11)0.0908 (13)0.0146 (10)
O80.0851 (12)0.0926 (14)0.1211 (15)0.0113 (10)0.0675 (12)0.0081 (11)
N10.0447 (9)0.0748 (13)0.0567 (10)0.0156 (8)0.0290 (8)0.0017 (9)
N30.0438 (9)0.0791 (14)0.1104 (16)−0.0068 (9)0.0462 (10)−0.0360 (11)
N50.0622 (11)0.0797 (14)0.0520 (11)0.0232 (10)0.0293 (9)0.0050 (9)
C20.0385 (10)0.0779 (16)0.0564 (13)0.0058 (10)0.0224 (9)−0.0146 (12)
C40.0348 (10)0.0810 (17)0.0710 (14)0.0039 (10)0.0206 (10)−0.0295 (12)
C50.0441 (10)0.0706 (15)0.0443 (11)0.0153 (10)0.0196 (9)−0.0054 (10)
C60.0468 (11)0.0790 (16)0.0500 (12)0.0149 (10)0.0270 (9)0.0049 (11)
N60.0370 (8)0.0558 (10)0.0650 (10)−0.0021 (7)0.0260 (8)−0.0019 (8)
N70.0370 (8)0.0462 (9)0.0559 (10)0.0036 (7)0.0182 (7)0.0055 (7)
N80.0393 (8)0.0468 (9)0.0625 (10)0.0031 (7)0.0289 (7)0.0130 (8)
C70.0377 (10)0.0504 (12)0.0524 (11)−0.0005 (8)0.0257 (8)0.0006 (9)
C80.0458 (10)0.0578 (13)0.0475 (11)−0.0093 (9)0.0191 (9)−0.0011 (9)
C90.0752 (15)0.0629 (16)0.0913 (18)−0.0108 (12)0.0452 (14)−0.0139 (13)
C100.104 (2)0.0608 (17)0.101 (2)−0.0072 (16)0.0347 (18)−0.0097 (15)
C110.105 (2)0.070 (2)0.0763 (19)−0.0331 (18)0.0098 (17)0.0112 (15)
C120.0807 (19)0.105 (2)0.0703 (18)−0.0443 (18)0.0218 (15)0.0132 (16)
C130.0525 (12)0.0899 (18)0.0590 (13)−0.0203 (12)0.0249 (10)0.0025 (12)
C140.0392 (9)0.0431 (11)0.0566 (12)0.0040 (8)0.0256 (9)0.0000 (9)
C150.0956 (18)0.0578 (14)0.0655 (15)−0.0198 (13)0.0378 (13)0.0029 (11)
C160.137 (3)0.081 (2)0.092 (2)−0.0555 (19)0.057 (2)−0.0047 (16)
C170.0882 (18)0.0767 (18)0.088 (2)−0.0355 (14)0.0420 (16)−0.0208 (14)
C180.0613 (13)0.0670 (15)0.0630 (14)−0.0035 (11)0.0288 (11)−0.0089 (11)
C190.0505 (11)0.0527 (12)0.0600 (13)0.0007 (9)0.0321 (10)0.0009 (10)
C200.0417 (10)0.0421 (11)0.0577 (12)0.0052 (8)0.0299 (9)0.0059 (9)
C210.0543 (12)0.0613 (13)0.0646 (13)0.0073 (10)0.0359 (11)0.0101 (10)
C220.0781 (16)0.0782 (16)0.0897 (17)0.0069 (13)0.0643 (15)0.0110 (13)
C230.0579 (14)0.0906 (18)0.112 (2)−0.0022 (12)0.0608 (16)−0.0005 (15)
C240.0425 (11)0.1013 (19)0.0818 (17)0.0049 (11)0.0329 (11)−0.0025 (14)
C250.0440 (11)0.0753 (15)0.0620 (13)0.0082 (10)0.0291 (10)0.0074 (11)
Geometric parameters (Å, °) top
O2—C21.231 (3)C11—C121.356 (4)
O4—C41.234 (2)C11—H110.9300
O7—N51.224 (2)C12—C131.369 (4)
O8—N51.233 (2)C12—H120.9300
N1—C61.322 (3)C13—H130.9300
N1—C21.362 (3)C14—C151.367 (3)
N3—C41.371 (3)C14—C191.375 (3)
N3—C21.379 (3)C15—C161.376 (3)
N3—H30.8600C15—H150.9300
N5—C51.422 (3)C16—C171.364 (4)
C4—C51.434 (3)C16—H160.9300
C5—C61.380 (3)C17—C181.356 (3)
C6—H60.9300C17—H170.9300
N6—C71.333 (2)C18—C191.368 (3)
N6—C81.422 (2)C18—H180.9300
N6—H6A0.8600C19—H190.9300
N7—C71.330 (2)C20—C251.373 (3)
N7—C141.425 (2)C20—C211.374 (3)
N7—H70.8600C21—C221.383 (3)
N8—C71.337 (2)C21—H210.9300
N8—C201.428 (2)C22—C231.368 (3)
N8—H80.8600C22—H220.9300
C8—C91.373 (3)C23—C241.367 (3)
C8—C131.378 (3)C23—H230.9300
C9—C101.383 (4)C24—C251.382 (3)
C9—H90.9300C24—H240.9300
C10—C111.375 (5)C25—H250.9300
C10—H100.9300
C6—N1—C2117.20 (18)C11—C12—C13121.5 (3)
C4—N3—C2127.8 (2)C11—C12—H12119.2
C4—N3—H3116.1C13—C12—H12119.2
C2—N3—H3116.1C12—C13—C8119.7 (3)
O7—N5—O8121.2 (2)C12—C13—H13120.2
O7—N5—C5119.5 (2)C8—C13—H13120.2
O8—N5—C5119.33 (18)C15—C14—C19119.88 (18)
O2—C2—N1122.85 (19)C15—C14—N7119.08 (18)
O2—C2—N3119.2 (2)C19—C14—N7121.02 (17)
N1—C2—N3117.9 (2)C14—C15—C16119.6 (2)
O4—C4—N3119.4 (2)C14—C15—H15120.2
O4—C4—C5129.0 (2)C16—C15—H15120.2
N3—C4—C5111.65 (18)C17—C16—C15120.2 (2)
C6—C5—N5118.7 (2)C17—C16—H16119.9
C6—C5—C4119.1 (2)C15—C16—H16119.9
N5—C5—C4122.10 (18)C18—C17—C16120.2 (2)
N1—C6—C5126.0 (2)C18—C17—H17119.9
N1—C6—H6117.0C16—C17—H17119.9
C5—C6—H6117.0C17—C18—C19120.2 (2)
C7—N6—C8127.70 (17)C17—C18—H18119.9
C7—N6—H6A116.1C19—C18—H18119.9
C8—N6—H6A116.1C18—C19—C14120.0 (2)
C7—N7—C14124.30 (15)C18—C19—H19120.0
C7—N7—H7117.8C14—C19—H19120.0
C14—N7—H7117.8C25—C20—C21120.68 (18)
C7—N8—C20124.48 (15)C25—C20—N8119.28 (18)
C7—N8—H8117.8C21—C20—N8119.99 (17)
C20—N8—H8117.8C20—C21—C22119.4 (2)
N7—C7—N6118.00 (16)C20—C21—H21120.3
N7—C7—N8121.24 (16)C22—C21—H21120.3
N6—C7—N8120.75 (17)C23—C22—C21119.9 (2)
C9—C8—C13119.7 (2)C23—C22—H22120.1
C9—C8—N6123.18 (19)C21—C22—H22120.1
C13—C8—N6117.1 (2)C24—C23—C22120.7 (2)
C8—C9—C10119.4 (3)C24—C23—H23119.7
C8—C9—H9120.3C22—C23—H23119.7
C10—C9—H9120.3C23—C24—C25119.9 (2)
C11—C10—C9120.7 (3)C23—C24—H24120.0
C11—C10—H10119.6C25—C24—H24120.0
C9—C10—H10119.6C20—C25—C24119.5 (2)
C12—C11—C10118.9 (3)C20—C25—H25120.3
C12—C11—H11120.5C24—C25—H25120.3
C10—C11—H11120.5
C6—N1—C2—O2−176.90 (19)C8—C9—C10—C11−1.8 (4)
C6—N1—C2—N32.8 (3)C9—C10—C11—C12−0.1 (4)
C4—N3—C2—O2173.4 (2)C10—C11—C12—C131.1 (4)
C4—N3—C2—N1−6.2 (3)C11—C12—C13—C8−0.2 (4)
C2—N3—C4—O4−174.6 (2)C9—C8—C13—C12−1.7 (3)
C2—N3—C4—C55.8 (3)N6—C8—C13—C12−179.87 (19)
O7—N5—C5—C6−169.02 (19)C7—N7—C14—C15−141.8 (2)
O8—N5—C5—C612.0 (3)C7—N7—C14—C1939.8 (3)
O7—N5—C5—C49.4 (3)C19—C14—C15—C16−0.8 (4)
O8—N5—C5—C4−169.6 (2)N7—C14—C15—C16−179.2 (2)
O4—C4—C5—C6178.0 (2)C14—C15—C16—C17−0.2 (5)
N3—C4—C5—C6−2.4 (3)C15—C16—C17—C180.4 (5)
O4—C4—C5—N5−0.4 (3)C16—C17—C18—C190.3 (4)
N3—C4—C5—N5179.21 (18)C17—C18—C19—C14−1.3 (3)
C2—N1—C6—C50.1 (3)C15—C14—C19—C181.5 (3)
N5—C5—C6—N1178.24 (18)N7—C14—C19—C18179.85 (18)
C4—C5—C6—N1−0.2 (3)C7—N8—C20—C25−136.65 (19)
C14—N7—C7—N6−152.77 (18)C7—N8—C20—C2145.7 (3)
C14—N7—C7—N826.0 (3)C25—C20—C21—C221.2 (3)
C8—N6—C7—N7−168.86 (18)N8—C20—C21—C22178.88 (19)
C8—N6—C7—N812.4 (3)C20—C21—C22—C23−0.6 (4)
C20—N8—C7—N731.5 (3)C21—C22—C23—C24−0.4 (4)
C20—N8—C7—N6−149.75 (18)C22—C23—C24—C250.8 (4)
C7—N6—C8—C934.2 (3)C21—C20—C25—C24−0.8 (3)
C7—N6—C8—C13−147.7 (2)N8—C20—C25—C24−178.5 (2)
C13—C8—C9—C102.7 (3)C23—C24—C25—C20−0.2 (4)
N6—C8—C9—C10−179.3 (2)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N6—H6A···O2i0.861.942.794 (2)174
N7—H7···N1i0.862.212.934 (2)142
N8—H8···O4ii0.862.052.887 (2)163
Symmetry codes: (i) −x+2, −y, −z+1; (ii) x, −y+1/2, z−1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N6—H6A···O2i0.861.942.794 (2)174
N7—H7···N1i0.862.212.934 (2)142
N8—H8···O4ii0.862.052.887 (2)163
Symmetry codes: (i) −x+2, −y, −z+1; (ii) x, −y+1/2, z−1/2.
Acknowledgements top

This work was supported by Fundação para a Ciência e a Tecnologia (FCT) under project POCI/FIS/58309/2004

references
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