organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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2-Phenyl­anilinium di­hydrogen phosphate

aLaboratoire de Chimie des Matériaux, Faculté des Sciences de Bizerte, 7021 Zarzouna, Tunisia, bFaculté des Sciences de Gabes, Gabes, Tunisia, cChemistry Department and Centro di Strutturistica Diffrattometrica, University of Ferrara, Via L. Borsari 46, I-44121 Ferrara, Italy, and dMatériaux, Faculté des Sciences de Bizerte, 7021 Zarzouna, Tunisia
*Correspondence e-mail: cherif_bennasr@yahoo.fr

(Received 6 July 2010; accepted 2 September 2010; online 11 September 2010)

In the crystal structure of the title compound, C12H12N+·H2PO4, the dihydrogen phosphate anions and the 2-phenyl­anilinium cations are associated via O—H⋯O and N—H⋯O hydrogen bonds so as to build inorganic layers around the x = 1/2 plane. The organic entities are anchored between these layers through C—H⋯O hydrogen bonds, forming a three-dimensional infinite network. The dihedral angle between the aromatic rings is 44.7 (4)°.

Related literature

For related inorganic-organic materials, see: Mrad et al. (2006[Mrad, M. L., Ben Nasr, C. & Rzaigui, M. (2006). Mater. Res. Bull. 41, 1287-1294.]); Oueslati et al. (2009[Oueslati, J., Kefi, R., Lefebvre, F., Ben Nasr, C. & Rzaigui, M. (2009). Phosphorus Sulfur Silicon, 184, 499-513.]). For the organization of inorganic networks, see: Baoub & Jouini (1998[Baoub, L. & Jouini, A. (1998). J. Solid State Chem. 141, 343-351.]). For the geometry around the P atom, see: Kefi et al. (2007[Kefi, R., Abid, S., Ben Nasr, C. & Rzaigui, M. (2007). Mater. Res. Bull. 42, 404-412.]); Oueslati & Ben Nasr (2006[Oueslati, A. & Ben Nasr, C. (2006). Anal. Sci. X-ray Struct. Online, 22, 225-226.]).

[Scheme 1]

Experimental

Crystal data
  • C12H12N+·H2PO4

  • Mr = 267.21

  • Monoclinic, P 21 /c

  • a = 15.4580 (4) Å

  • b = 4.7422 (1) Å

  • c = 18.4765 (6) Å

  • β = 112.008 (1)°

  • V = 1255.72 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.23 mm−1

  • T = 295 K

  • 0.26 × 0.23 × 0.11 mm

Data collection
  • Nonius KappaCCD diffractometer

  • 11492 measured reflections

  • 3628 independent reflections

  • 2106 reflections with I > 2σ(I)

  • Rint = 0.089

Refinement
  • R[F2 > 2σ(F2)] = 0.054

  • wR(F2) = 0.137

  • S = 1.04

  • 3628 reflections

  • 183 parameters

  • 5 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.26 e Å−3

  • Δρmin = −0.36 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O1i 0.90 (2) 2.07 (2) 2.950 (2) 167 (3)
N1—H2⋯O3 0.92 (3) 1.90 (3) 2.818 (3) 171 (2)
N1—H3⋯O1ii 0.90 (3) 1.83 (2) 2.727 (2) 173 (2)
O2—H13⋯O3iii 0.85 (2) 1.66 (2) 2.500 (2) 171 (3)
O4—H14⋯O4iv 0.80 (3) 2.00 (3) 2.797 (3) 172 (5)
C2—H4⋯O2 0.93 2.51 3.376 (3) 156
C9—H9⋯O2v 0.93 2.56 3.407 (3) 151
Symmetry codes: (i) -x+1, -y, -z+1; (ii) -x+1, -y+1, -z+1; (iii) x, y+1, z; (iv) [-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (v) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Data collection: KappaCCD Server Software (Nonius, 1997[Nonius (1997). KappaCCD Server Software. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO-SMN; program(s) used to solve structure: SIR97 (Altomare et al., 1999[Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115-119.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

During the systematic investigation of interaction between monophosphoric acid with organic molecules, numerous structures of monophosphates with organic cations have been described (Oueslati et al., 2009; Mrad et al., 2OO6). These structures are based on various one-, two-, or three-dimensional inorganic network depending on the nature and the shape of the organic molecule (Baoub and Jouini, 1998). Hydrogen bonds take part to the stability and the cohesion of the corresponding compounds. We report, in this work, the chemical preparation and the structural investigation of a new 2-Phenylanilinium dihydrogenomonophosphate. As shown in Fig. 1, the crystal structure of the title compound (I), consists of one phosphate anion and one organic cation. The H2PO4- entities and the NH3+ ammonium catins have a layered organization around x = 1/2 plane (Fig. 2). Fig. 3 represents a projection of such layer. It shows that the H2PO4- groups are connected by strong hydrogen bonds to form infinite chains in the b-direction of composition (H2PO4-)nn-. Each chain is interconnected, on one hand, to another one by means of O—H···O hydrogen bonds and, on the other hand, to NH3+ groups via N—H···O hydrogen bonds as to build an inorganic layer. The organic groups are anchored onto successive inorganic layers throw C—H···O hydrogen bonds (Fig. 2).

With regards to the H2PO4- geometrical features, we remark the existence of two types of P···O distances. The longest ones (1.557 (2) and 1.595 (2) Å) correspond to P—OH groups, the shortest ones (1.494 (2) and 1.504 (2) Å) corresponding to classical P···O bonds. The average of the P···O distances and the O—P—O angles are 1.537 (2) Å and 109.35 (10)°, respectively. They agree perfectly with that generally observed for anions in other phosphates (Kefi et al., 2OO7). The O—P—O angles spread in the range 104.87 (10) and 115.19 (10)°. This distortion from the ideal tetrahedral value has been regularly noted in other organic phosphates (Oueslati and Ben Nasr, 2006). The larger mean value of 112.70 (10)°, with a range of 110.74 (11)–115.19 (10)°, corresponds to the O—P—O angle. The smaller one 106.00 (10)°, with a range of 104.88 (10)–107.89 (10)°, is related to the HO—P—OH angle. All these geometrical parameters are in full agreement with those observed in such anions in other organic dihydrogenomonophosphates (Oueslati and Ben Nasr, 2006). However, the P—P distance between H2PO4 tetrahedra: 4.742 (2) ° is slightly shorter than that observed in NH3(CH2)4NH3HPO4.H2O (Baoub and Jouini, 1998) [5.575 (1) °], which is probably due to the presence of two acidic hydrogen atoms on the PO4 leading to the formation of strong hydrogen bonds. Furthermore, the short P—P distance is in favour of the general formation of [H2PO4-]nn- polyanions in the crystal structure, but not to the individualization of the H2PO4- groups (Oueslati and Ben Nasr, 2006).

Related literature top

For related inorganic-organic materials, see: Mrad et al. (2006); Oueslati et al. (2009). For the organization of inorganic networks, see: Baoub & Jouini (1998). For the geometry around the P atom, see: Kefi et al. (2007); Oueslati & Ben Nasr (2006).

Experimental top

Crystals of the title compound have been prepared in a Petri dish by adding 50 mmol of concentrated orthophosphoric acid (Fluka, 85%, d = 1.7) to 25 mmol of 2-phenylaniline (Acros) dissolved in ethanol. After agitation, the resulting solution has been slowly evaporated at room temperature until the formation of single crystals suitable for X-ray structure analysis and remained stable under normal conditions of temperature and humidity.

Refinement top

Hydrogen atoms bound to N and O atoms were located in the Difference Fourier map and refined with restraints on the bond length [0.87 (2) and 0.84 (2) for N—H and O—H, respectively] ; the remaining H atoms were given calculated positions (C–H: 0.93Å) . In all cases riding displacement factors were used, with a multiplication factor of 1.2.

Computing details top

Data collection: KappaCCD Server Software (Nonius, 1997); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. A view of (I), showing 50% probability displacement ellipsoids and arbitrary spheres for the H atoms.
[Figure 2] Fig. 2. The packing diagram of the compound viewed down the b axis. PO4 is given in the tetrahedral representation. Hydrogen bonds are shown as dashed lines.
[Figure 3] Fig. 3. The packing diagram of the compound viewed down the a axis. PO4 is given in the tetrahedral representation. Hydrogen bonds are shown as dashed lines.
2-Phenylanilinium dihydrogen phosphate top
Crystal data top
C12H12N+·H2PO4F(000) = 560
Mr = 267.21Dx = 1.413 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 11492 reflections
a = 15.4580 (4) Åθ = 5.0–30.0°
b = 4.7422 (1) ŵ = 0.23 mm1
c = 18.4765 (6) ÅT = 295 K
β = 112.008 (1)°Plate, colourless
V = 1255.72 (6) Å30.26 × 0.23 × 0.11 mm
Z = 4
Data collection top
Nonius KappaCCD
diffractometer
2106 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.089
Graphite monochromatorθmax = 30.2°, θmin = 5.3°
ϕ and ω scansh = 2121
11492 measured reflectionsk = 66
3628 independent reflectionsl = 2524
Refinement top
Refinement on F25 restraints
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.054 w = 1/[σ2(Fo2) + (0.0566P)2 + 0.2547P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.137(Δ/σ)max = 0.001
S = 1.04Δρmax = 0.26 e Å3
3628 reflectionsΔρmin = 0.36 e Å3
183 parameters
Crystal data top
C12H12N+·H2PO4V = 1255.72 (6) Å3
Mr = 267.21Z = 4
Monoclinic, P21/cMo Kα radiation
a = 15.4580 (4) ŵ = 0.23 mm1
b = 4.7422 (1) ÅT = 295 K
c = 18.4765 (6) Å0.26 × 0.23 × 0.11 mm
β = 112.008 (1)°
Data collection top
Nonius KappaCCD
diffractometer
2106 reflections with I > 2σ(I)
11492 measured reflectionsRint = 0.089
3628 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0545 restraints
wR(F2) = 0.137H atoms treated by a mixture of independent and constrained refinement
S = 1.04Δρmax = 0.26 e Å3
3628 reflectionsΔρmin = 0.36 e Å3
183 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
P10.50007 (4)0.34843 (11)0.37476 (3)0.03014 (17)
O10.59397 (10)0.4449 (3)0.42905 (9)0.0387 (4)
O20.42429 (11)0.5807 (3)0.36048 (11)0.0442 (4)
H130.441 (2)0.751 (4)0.3706 (19)0.078 (11)*
O30.46470 (12)0.0835 (3)0.39908 (10)0.0391 (4)
O40.50106 (13)0.2818 (4)0.29045 (10)0.0447 (4)
H140.506 (3)0.425 (6)0.269 (2)0.098 (14)*
N10.34451 (13)0.0832 (4)0.48207 (12)0.0338 (4)
H10.3538 (18)0.079 (4)0.5088 (15)0.049 (8)*
H20.3783 (15)0.083 (5)0.4503 (13)0.039 (7)*
H30.3664 (19)0.231 (5)0.5148 (15)0.058 (8)*
C10.24645 (15)0.1339 (5)0.43239 (13)0.0352 (5)
C20.22923 (18)0.2634 (6)0.36147 (15)0.0492 (6)
H40.27880.3160.34740.059*
C30.13871 (19)0.3153 (7)0.31125 (16)0.0575 (7)
H50.12690.4020.26330.069*
C40.06575 (18)0.2368 (7)0.33299 (16)0.0548 (7)
H60.00450.26970.29950.066*
C50.08346 (17)0.1110 (6)0.40363 (15)0.0472 (6)
H70.03350.05990.41730.057*
C60.17466 (16)0.0565 (5)0.45629 (14)0.0378 (5)
C70.18893 (16)0.0716 (5)0.53375 (14)0.0400 (5)
C80.25463 (17)0.0340 (6)0.60238 (14)0.0458 (6)
H80.29270.18330.60050.055*
C90.2639 (2)0.0821 (7)0.67409 (16)0.0601 (8)
H90.30890.01270.71980.072*
C100.2068 (2)0.2983 (7)0.67742 (19)0.0642 (8)
H100.21290.37510.72540.077*
C110.1406 (2)0.4018 (7)0.6100 (2)0.0659 (9)
H110.10150.5470.61260.079*
C120.13193 (19)0.2921 (6)0.53876 (17)0.0508 (6)
H120.08750.36590.49340.061*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
P10.0349 (3)0.0253 (3)0.0303 (3)0.0000 (2)0.0123 (2)0.0027 (2)
O10.0337 (8)0.0377 (8)0.0398 (9)0.0021 (6)0.0080 (7)0.0056 (7)
O20.0355 (9)0.0292 (9)0.0612 (12)0.0030 (7)0.0104 (8)0.0065 (7)
O30.0502 (9)0.0277 (7)0.0448 (10)0.0024 (7)0.0239 (8)0.0012 (6)
O40.0651 (11)0.0398 (9)0.0326 (9)0.0012 (8)0.0223 (8)0.0027 (7)
N10.0291 (9)0.0379 (11)0.0336 (11)0.0007 (8)0.0108 (8)0.0024 (8)
C10.0307 (10)0.0397 (12)0.0310 (11)0.0007 (9)0.0068 (9)0.0052 (9)
C20.0394 (13)0.0655 (17)0.0417 (15)0.0008 (12)0.0141 (11)0.0059 (12)
C30.0472 (15)0.079 (2)0.0399 (15)0.0082 (14)0.0085 (12)0.0140 (14)
C40.0349 (13)0.0761 (18)0.0423 (15)0.0040 (13)0.0016 (11)0.0018 (13)
C50.0307 (12)0.0621 (16)0.0456 (14)0.0016 (11)0.0106 (10)0.0032 (12)
C60.0342 (11)0.0428 (12)0.0358 (12)0.0021 (10)0.0122 (10)0.0060 (10)
C70.0359 (12)0.0459 (13)0.0411 (13)0.0055 (10)0.0175 (10)0.0019 (10)
C80.0399 (12)0.0604 (15)0.0390 (14)0.0013 (12)0.0169 (11)0.0035 (12)
C90.0544 (16)0.088 (2)0.0389 (15)0.0158 (15)0.0186 (13)0.0020 (14)
C100.071 (2)0.077 (2)0.0562 (19)0.0182 (17)0.0371 (16)0.0226 (16)
C110.070 (2)0.0591 (18)0.084 (2)0.0060 (15)0.0460 (19)0.0164 (16)
C120.0467 (14)0.0524 (15)0.0586 (17)0.0005 (12)0.0258 (13)0.0008 (13)
Geometric parameters (Å, º) top
P1—O11.4937 (16)C4—C51.366 (4)
P1—O31.5045 (15)C4—H60.93
P1—O21.5566 (16)C5—C61.405 (3)
P1—O41.5952 (17)C5—H70.93
O2—H130.844 (18)C6—C71.493 (3)
O4—H140.807 (18)C7—C81.388 (3)
N1—C11.468 (3)C7—C121.393 (4)
N1—H10.895 (17)C8—C91.392 (4)
N1—H20.921 (16)C8—H80.93
N1—H30.905 (17)C9—C101.368 (4)
C1—C21.380 (3)C9—H90.93
C1—C61.389 (3)C10—C111.372 (5)
C2—C31.381 (4)C10—H100.93
C2—H40.93C11—C121.375 (4)
C3—C41.383 (4)C11—H110.93
C3—H50.93C12—H120.93
O1—P1—O3115.19 (10)C3—C4—H6119.9
O1—P1—O2112.16 (9)C4—C5—C6122.1 (2)
O3—P1—O2107.87 (10)C4—C5—H7118.9
O1—P1—O4110.73 (10)C6—C5—H7118.9
O3—P1—O4105.30 (9)C1—C6—C5116.4 (2)
O2—P1—O4104.88 (10)C1—C6—C7124.3 (2)
P1—O2—H13120 (2)C5—C6—C7119.2 (2)
P1—O4—H14111 (3)C8—C7—C12118.4 (2)
C1—N1—H1113.6 (18)C8—C7—C6121.6 (2)
C1—N1—H2107.5 (15)C12—C7—C6120.0 (2)
H1—N1—H2110 (2)C9—C8—C7120.4 (3)
C1—N1—H3109.3 (18)C9—C8—H8119.8
H1—N1—H3111 (2)C7—C8—H8119.8
H2—N1—H3105 (2)C10—C9—C8120.1 (3)
C2—C1—C6121.8 (2)C10—C9—H9120
C2—C1—N1117.0 (2)C8—C9—H9120
C6—C1—N1121.3 (2)C11—C10—C9120.1 (3)
C1—C2—C3120.2 (2)C11—C10—H10120
C1—C2—H4119.9C9—C10—H10120
C3—C2—H4119.9C10—C11—C12120.4 (3)
C2—C3—C4119.2 (3)C10—C11—H11119.8
C2—C3—H5120.4C12—C11—H11119.8
C4—C3—H5120.4C11—C12—C7120.7 (3)
C5—C4—C3120.1 (2)C11—C12—H12119.7
C5—C4—H6119.9C7—C12—H12119.7
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O1i0.90 (2)2.07 (2)2.950 (2)167 (3)
N1—H2···O30.92 (3)1.90 (3)2.818 (3)171 (2)
N1—H3···O1ii0.90 (3)1.83 (2)2.727 (2)173 (2)
O2—H13···O3iii0.85 (2)1.66 (2)2.500 (2)171 (3)
O4—H14···O4iv0.80 (3)2.00 (3)2.797 (3)172 (5)
C2—H4···O20.932.513.376 (3)156
C9—H9···O2v0.932.563.407 (3)151
Symmetry codes: (i) x+1, y, z+1; (ii) x+1, y+1, z+1; (iii) x, y+1, z; (iv) x+1, y+1/2, z+1/2; (v) x, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC12H12N+·H2PO4
Mr267.21
Crystal system, space groupMonoclinic, P21/c
Temperature (K)295
a, b, c (Å)15.4580 (4), 4.7422 (1), 18.4765 (6)
β (°) 112.008 (1)
V3)1255.72 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.23
Crystal size (mm)0.26 × 0.23 × 0.11
Data collection
DiffractometerNonius KappaCCD
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
11492, 3628, 2106
Rint0.089
(sin θ/λ)max1)0.707
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.054, 0.137, 1.04
No. of reflections3628
No. of parameters183
No. of restraints5
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.26, 0.36

Computer programs: KappaCCD Server Software (Nonius, 1997), DENZO-SMN (Otwinowski & Minor, 1997), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O1i0.90 (2)2.07 (2)2.950 (2)167 (3)
N1—H2···O30.92 (3)1.90 (3)2.818 (3)171 (2)
N1—H3···O1ii0.90 (3)1.83 (2)2.727 (2)173 (2)
O2—H13···O3iii0.85 (2)1.66 (2)2.500 (2)171 (3)
O4—H14···O4iv0.80 (3)2.00 (3)2.797 (3)172 (5)
C2—H4···O20.93002.51003.376 (3)156.00
C9—H9···O2v0.93002.56003.407 (3)151.00
Symmetry codes: (i) x+1, y, z+1; (ii) x+1, y+1, z+1; (iii) x, y+1, z; (iv) x+1, y+1/2, z+1/2; (v) x, y+1/2, z+1/2.
 

Acknowledgements

We would like to acknowledge the support provided by the Secretary of State for Scientific Research and Technology of Tunisia.

References

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