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ISSN: 2056-9890

4-Cyano­anilinium iodide

aDepartment of Chemistry, Tulane University, New Orleans, LA 70118, USA, bDepartment of Biological Sciences, Loyola University, New Orleans, LA 70118, USA, cDepartment of Physics, Loyola University, New Orleans, LA 70118, USA, and dDepartment of Chemistry, Loyola University, New Orleans, LA 70118, USA
*Correspondence e-mail: joelt@tulane.edu

(Received 12 July 2012; accepted 24 July 2012; online 1 August 2012)

In the title compound, C7H7N2+·I, the cation is located on a site of 4mm symmetry and is thus disordered about the fourfold axis so that there are two perpendicular orientations of the six-membered ring and four rotational orientations of the {–NH3+} group. In the crystal, there are two layers perpendicular to the c axis, each containing iodide ions and the {–NH3+} portions of the cations, with the remainder of the cations extending outwards from these layers.

Related literature

For the structure of 4-cyano­anilinium chloride, see: Colapietro et al. (1981[Colapietro, M., Domenicano, A., Marciante, C. & Portalone, G. (1981). Acta Cryst. B37, 387-394.]). For the structure of 4-cyano­anilinium bromide, see: Vumbaco et al. (2012[Vumbaco, D. J., Kammer, M. N., Koplitz, L. V. & Mague, J. T. (2012). Acta Cryst. E68. Submitted (JJ2147).]). For the structure of anilinium iodide, see: Fecher & Weiss (1986[Fecher, G. & Weiss, A. (1986). Ber. Bunsenges. Phys. Chem. 90, 10-21.]).

[Scheme 1]

Experimental

Crystal data
  • C7H7N2+·I

  • Mr = 246.05

  • Tetragonal, P 4/n m m

  • a = 4.9930 (4) Å

  • c = 16.445 (2) Å

  • V = 409.98 (8) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 3.83 mm−1

  • T = 100 K

  • 0.26 × 0.20 × 0.05 mm

Data collection
  • Bruker SMART APEX CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2009[Sheldrick, G. M. (2009). SADABS. University of Göttingen, Germany.]) Tmin = 0.362, Tmax = 0.844

  • 7082 measured reflections

  • 382 independent reflections

  • 381 reflections with I > 2σ(I)

  • Rint = 0.039

Refinement
  • R[F2 > 2σ(F2)] = 0.012

  • wR(F2) = 0.029

  • S = 1.14

  • 382 reflections

  • 31 parameters

  • H-atom parameters constrained

  • Δρmax = 0.46 e Å−3

  • Δρmin = −0.56 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯I1 0.88 2.72 3.5813 (5) 165
N1—H1A⋯I1i 0.88 2.87 3.5813 (5) 139
N1—H1B⋯I1ii 0.88 2.87 3.5813 (5) 139
Symmetry codes: (i) x-1, y, z; (ii) x, y-1, z.

Data collection: APEX2 (Bruker, 2010[Bruker (2010). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL).

Supporting information


Comment top

In the title compound, (C7H7N2)+.I-, the cation is located on a site of 4mm symmetry so is disordered over 2 sites rotated 90° from one another about the N1—C1···C4—C5N2 axis. This leads to a more extensive disorder of the (—NH3+) group so it is likely that there are a variety of N—H···I interactions of different geometries. To illustrate what one set of these could be, the best estimate of the rotational orientation of the (—NH3+) group obtained from a difference map was used to generate the values given in Table 1. These interactions lead to a layer of anions with the (—NH3+) groups largely in the layer and the remainder of the cations projecting perpendicular to the layer. Two of these layers are then associated in a head–to–head fashion via electrostatic N1+···I1- interactions of 3.513 (1)Å leading to a bilayer of iodide and (—NH3+) groups with the remainders of the cations projecting out from both sides (Fig. 2). A similar layer structure is adopted by anilinium iodide (Fecher & Weiss, 1986) while the packings for 4–cyanoanilinium bromide (Vumbaco et al., 2012) and the corresponding chloride salt (Colapietro et al., 1981) are quite different.

Related literature top

For the structure of 4-cyanoanilinium chloride, see: Colapietro et al. (1981). For the structure of 4-cyanoanilinium bromide, see: Vumbaco et al. (2012). For the structure of anilinium iodide, see: Fecher & Weiss (1986).

Experimental top

The 0.55 g of 4–cyanoaniline and 1.0 ml of aqueous hydroiodic acid (47% by mass) were combined in 10 ml of ethanol. This solution was slowly evaporated to dryness under ambient conditions to form crystals of the title compound.

Refinement top

The cation sits on a special position requiring 4 mm symmetry with the 4–fold axis running through both N atoms and the attached carbons. Thus the carbon atoms at the 2– and 3–positions are effectively disordered over two sites and two orientations of each were used in the refinement. H atoms attached to these carbons were placed in calculated positions with C—H = 0.95Å. A small peak in a position to be one location for a hydrogen bound to N1 could be seen in a difference map and its position was used to calculate positions for the remainder of one of the orientations of the —NH3+ unit in which the N—H distance was adjusted to be 0.88Å. All H atoms were included as riding contributions with Uiso(H) = 1.2Ueq(C, N).

Computing details top

Data collection: APEX2 (Bruker, 2010); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. View of the cation–anion pair with with the atom numbering scheme. Displacement ellipsoids are drawn at 50% probability level. H atoms are presented as a small spheres of arbitrary radius. Symmetry code: (i) -x+1/2, -y+1/2, z.
[Figure 2] Fig. 2. Packing showing the cation–anion bilayer perpendicular to the c axis. N—H···I interactions are shown as dashed lines and the electrostatic N+···I- interactions as dotted lines. Colour key: purple = I, blue = N, gray = C, orange = H.
4-Cyanoanilinium iodide top
Crystal data top
C7H7N2+·IDx = 1.993 Mg m3
Mr = 246.05Mo Kα radiation, λ = 0.71073 Å
Tetragonal, P4/nmmCell parameters from 8495 reflections
Hall symbol: -P 4a 2aθ = 2.5–29.1°
a = 4.9930 (4) ŵ = 3.83 mm1
c = 16.445 (2) ÅT = 100 K
V = 409.98 (8) Å3Plate, colourless
Z = 20.26 × 0.20 × 0.05 mm
F(000) = 232
Data collection top
Bruker SMART APEX CCD
diffractometer
382 independent reflections
Radiation source: fine–focus sealed tube381 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.039
ϕ and ω scansθmax = 29.1°, θmin = 2.5°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2009)
h = 66
Tmin = 0.362, Tmax = 0.844k = 66
7082 measured reflectionsl = 2222
Refinement top
Refinement on F2Primary atom site location: heavy atom
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.012Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.029H-atom parameters constrained
S = 1.14 w = 1/[σ2(Fo2) + (0.0165P)2 + 0.1447P]
where P = (Fo2 + 2Fc2)/3
382 reflections(Δ/σ)max = 0.002
31 parametersΔρmax = 0.46 e Å3
0 restraintsΔρmin = 0.56 e Å3
Crystal data top
C7H7N2+·IZ = 2
Mr = 246.05Mo Kα radiation
Tetragonal, P4/nmmµ = 3.83 mm1
a = 4.9930 (4) ÅT = 100 K
c = 16.445 (2) Å0.26 × 0.20 × 0.05 mm
V = 409.98 (8) Å3
Data collection top
Bruker SMART APEX CCD
diffractometer
382 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2009)
381 reflections with I > 2σ(I)
Tmin = 0.362, Tmax = 0.844Rint = 0.039
7082 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0120 restraints
wR(F2) = 0.029H-atom parameters constrained
S = 1.14Δρmax = 0.46 e Å3
382 reflectionsΔρmin = 0.56 e Å3
31 parameters
Special details top

Experimental. The diffraction data were obtained from 3 sets of 400 frames, each of width 0.5° in ω, colllected at ϕ = 0.00°, 90.00° and 180.00° and 2 sets of 800 frames, each of width 0.45° in ϕ, collected at ω = -30.00° and 210.00°. The scan time was 10 sec/frame.

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 > 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*/UeqOcc. (<1)
I10.75000.75000.588552 (10)0.01472 (8)
N10.25000.25000.62508 (16)0.0199 (5)
H10.36620.36620.60570.024*0.25
H1A0.08870.29040.60730.024*0.125
H1B0.29040.08870.60730.024*0.125
N20.25000.25001.03941 (17)0.0226 (6)
C10.25000.25000.71467 (18)0.0139 (5)
C20.4934 (6)0.25000.75539 (17)0.0174 (5)0.50
H20.65760.25000.72620.021*0.50
C30.4936 (6)0.25000.84022 (16)0.0171 (5)0.50
H30.65830.25000.86920.020*0.50
C40.25000.25000.88189 (18)0.0143 (5)
C50.25000.25000.97006 (19)0.0174 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
I10.01513 (9)0.01513 (9)0.01392 (11)0.0000.0000.000
N10.0236 (8)0.0236 (8)0.0126 (11)0.0000.0000.000
N20.0252 (9)0.0252 (9)0.0174 (12)0.0000.0000.000
C10.0129 (8)0.0129 (8)0.0158 (12)0.0000.0000.000
C20.0132 (12)0.0225 (14)0.0163 (11)0.0000.0020 (10)0.000
C30.0129 (12)0.0226 (13)0.0157 (11)0.0000.0022 (11)0.000
C40.0146 (8)0.0146 (8)0.0136 (13)0.0000.0000.000
C50.0161 (9)0.0161 (9)0.0200 (14)0.0000.0000.000
Geometric parameters (Å, º) top
N1—C11.473 (4)C2—C31.395 (4)
N1—H10.8800C2—H20.9500
N1—H1A0.8800C3—C41.396 (3)
N1—H1B0.8800C3—H30.9500
N2—C51.141 (4)C4—C3i1.396 (3)
C1—C2i1.388 (3)C4—C51.450 (4)
C1—C21.388 (3)
C1—N1—H1111.2C1—C2—H2120.8
C1—N1—H1A109.4C3—C2—H2120.3
H1—N1—H1A109.4C2—C3—C4119.3 (3)
C1—N1—H1B109.4C2—C3—H3120.1
H1—N1—H1B109.4C4—C3—H3120.5
H1A—N1—H1B108.0C3i—C4—C3121.2 (3)
C2i—C1—C2122.3 (3)C3i—C4—C5119.39 (15)
C2i—C1—N1118.85 (16)C3—C4—C5119.39 (15)
C2—C1—N1118.85 (16)N2—C5—C4180.000 (1)
C1—C2—C3118.9 (3)
C2i—C1—C2—C30.000 (2)C1—C2—C3—C40.000 (2)
N1—C1—C2—C3180.000 (1)C2—C3—C4—C5180.000 (1)
Symmetry code: (i) x+1/2, y+1/2, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···I10.882.723.5813 (5)165
N1—H1A···I1ii0.882.873.5813 (5)139
N1—H1B···I1iii0.882.873.5813 (5)139
Symmetry codes: (ii) x1, y, z; (iii) x, y1, z.

Experimental details

Crystal data
Chemical formulaC7H7N2+·I
Mr246.05
Crystal system, space groupTetragonal, P4/nmm
Temperature (K)100
a, c (Å)4.9930 (4), 16.445 (2)
V3)409.98 (8)
Z2
Radiation typeMo Kα
µ (mm1)3.83
Crystal size (mm)0.26 × 0.20 × 0.05
Data collection
DiffractometerBruker SMART APEX CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2009)
Tmin, Tmax0.362, 0.844
No. of measured, independent and
observed [I > 2σ(I)] reflections
7082, 382, 381
Rint0.039
(sin θ/λ)max1)0.684
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.012, 0.029, 1.14
No. of reflections382
No. of parameters31
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.46, 0.56

Computer programs: APEX2 (Bruker, 2010), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···I10.882.723.5813 (5)165
N1—H1A···I1i0.882.873.5813 (5)139
N1—H1B···I1ii0.882.873.5813 (5)139
Symmetry codes: (i) x1, y, z; (ii) x, y1, z.
 

Acknowledgements

We thank the Chemistry Department of Tulane University for support of the X–ray laboratory and the Louisiana Board of Regents through the Louisiana Educational Quality Support Fund (grant LEQSF (2003–2003)–ENH–TR-67) for the purchase of the APEX diffractometer.

References

First citationBruker (2009). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationBruker (2010). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationColapietro, M., Domenicano, A., Marciante, C. & Portalone, G. (1981). Acta Cryst. B37, 387–394.  CSD CrossRef CAS Web of Science IUCr Journals Google Scholar
First citationFecher, G. & Weiss, A. (1986). Ber. Bunsenges. Phys. Chem. 90, 10–21.  CrossRef CAS Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSheldrick, G. M. (2009). SADABS. University of Göttingen, Germany.  Google Scholar
First citationVumbaco, D. J., Kammer, M. N., Koplitz, L. V. & Mague, J. T. (2012). Acta Cryst. E68. Submitted (JJ2147).  CrossRef IUCr Journals Google Scholar

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ISSN: 2056-9890
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