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

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1-Allyl-2-amino­pyridin-1-ium bromide

aDepartment of Physics, Government Arts College (Autonomous), Karur 639 005, India, bSchool of Chemistry, Bharathidasan University, Tiruchirappalli 620 024, India, cFaculty of Health and Life Sciences, Coventry University, Coventry CV1 5FB, England, and dDepartment of Bioinformatics, School of Chemical and Biotechnology, SASTRA University, Thanjavur 613 401, India
*Correspondence e-mail: thamu@scbt.sastra.edu

(Received 29 April 2013; accepted 7 May 2013; online 15 May 2013)

In the cation of the title salt, C8H11N2+·Br, the dihedral angle between the planes of the pyridinium ring and the allyl group is 79.4 (3)°. In the crystal, N—H⋯Br and weak C—H⋯Br hydrogen bonds link the cations and anions, forming chains of alternating R21(7) and R42(8) rings, which run parallel to the c-axis direction. The crystal studied was an inversion twin with components in a 0.753 (12):0.247 (12) ratio.

Related literature

For related structures, see: Seethalakshmi et al. (2006a[Seethalakshmi, T., Kaliannan, P., Venkatesan, P., Fronczek, F. R. & Thamotharan, S. (2006a). Acta Cryst. E62, o2353-o2355.],b[Seethalakshmi, T., Venkatesan, P., Fronczek, F. R., Kaliannan, P. & Thamotharan, S. (2006b). Acta Cryst. E62, o2560-o2562.],c[Seethalakshmi, T., Venkatesan, P., Fronczek, F. R., Kaliannan, P. & Thamotharan, S. (2006c). Acta Cryst. E62, o3389-o3390.], 2007[Seethalakshmi, T., Manivannan, S., Lynch, D. E., Dhanuskodi, S. & Kaliannan, P. (2007). Acta Cryst. E63, o599-o601.], 2013[Seethalakshmi, T., Manivannan, S., Dhanuskodi, S., Lynch, D. E. & Thamotharan, S. (2013). Acta Cryst. E69, o835-o836.]). For the biolgical activity of alkyl-pyridinium salts, see: Sundararaman et al. (2013[Sundararaman, M., Rajesh Kumar, R., Venkatesan, P. & Ilangovan, A. (2013). J. Med. Microbiol. 62, 241-248.]); Ilangovan et al. (2012[Ilangovan, A., Venkatesan, P., Sundararaman, M. & Rejesh Kumar, R. (2012). Med. Chem. Res. 21, 694-702.]). For hydrogen-bond graph-set motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C8H11N2+·Br

  • Mr = 215.10

  • Orthorhombic, P n a 21

  • a = 7.8205 (2) Å

  • b = 13.3560 (3) Å

  • c = 8.5621 (2) Å

  • V = 894.32 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 4.53 mm−1

  • T = 120 K

  • 0.30 × 0.14 × 0.03 mm

Data collection
  • Bruker–Nonius 95mm CCD camera on κ-goniostat diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.343, Tmax = 0.876

  • 14540 measured reflections

  • 2033 independent reflections

  • 1960 reflections with I > 2σ(I)

  • Rint = 0.058

Refinement
  • R[F2 > 2σ(F2)] = 0.023

  • wR(F2) = 0.053

  • S = 1.06

  • 2033 reflections

  • 110 parameters

  • 3 restraints

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

  • Δρmax = 0.43 e Å−3

  • Δρmin = −0.35 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 945 Friedel pairs

  • Flack parameter: 0.247 (12)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2A⋯Br1i 0.84 (2) 2.61 (2) 3.412 (2) 160 (4)
N2—H2B⋯Br1ii 0.85 (2) 2.51 (2) 3.357 (2) 175 (3)
C6—H6A⋯Br1iii 0.99 2.91 3.668 (3) 134
C6—H6B⋯Br1i 0.99 2.84 3.810 (3) 167
Symmetry codes: (i) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z]; (ii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (iii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Data collection: COLLECT (Nonius, 1998[Nonius (1998). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr and R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO; program(s) used to solve structure: SIR92 (Altomare et al., 1994[Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

As part of our studies on pyridinum salts (Seethalakshmi et al., 2006a,b,c, 2007, 2013), we report herein the crystal structure of the title compound, (I). The asymmetric unit of (I) is shown in Fig. 1. The dihedral angle between the planes of the pyridinium ring and allyl group (C6/C7/C8) is 79.4 (3)°. The corresponding bond lengths and angles of the cation in (I) are comparable with those of related structures reported earlier (Seethalakshmi et al., 2006a,b,c, 2007, 2013).

In the crystal (Fig. 2) the amino group acts as a donor for two different bromide anions (Table 1). These intermolecular N—H···Br hydrogen bonds link the cations via bromide anions into one-dimensional chains which run parallel to the c axis. In addition, weak intermolecular C—H···Br interactions are observed between C6 (via H6A and H6B) and two bromide anions. The N2—H2A···Br1i and C6—H6B···Br1i interactions combine to generate a R12(7) ring (Bernstein et al., 1995) and two N—H···O hydrogen bonds and two C—H···Br interactions combine to form a R24(8) ring motif. These two ring motifs are arranged alternately and run parallel to the c axis (Fig. 3).

Related literature top

For related structures, see: Seethalakshmi et al. (2006a,b,c, 2007, 2013). For the biolgical activity of alkyl-pyridinium salts, see: Sundararaman et al. (2013); Ilangovan et al. (2012). For hydrogen-bond graph-set motifs, see: Bernstein et al. (1995).

Experimental top

A solution of 2-aminopyridine (1.175 g, 25 ml) and allyl bromide (1.51 g, 25 ml) in dry acetone (15 ml) was stirred for 44 h at room temperature (303 K). The solid that separated was filtered, washed with dry acetone and dried in vacuum to give the stable salt, which was recrystallized from an aqueous ethanol (80% v/v) solution (m.p. 419–421 K, yield 63%).

Refinement top

The positions of amino H atoms were determined from a difference Fourier map and refined freely along with their isotropic displacement parameters. In the final round of refinement, the N—H bond lengths of amino group were restrained to 0.86 (2) Å. The remaining H atoms were placed in geometrically idealized positions (C—H = 0.95–0.99 Å), with Uiso(H) = 1.2Ueq(C) and were constrained to ride on their parent atoms. The crystal used is an inversion twin with components in the ratio 0.753 (12):0.247 (12)

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997); data reduction: DENZO (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of (I), showing ellipsoids at the 50% probability level.
[Figure 2] Fig. 2. Part of the crystal structure of (I) viewed along the a axis. The hydrogen bonds are indicated as dashed lines.
[Figure 3] Fig. 3. Arrangement of alternate R12(7) and R24(10) ring motifs in a one-dimensional chain.
1-Allyl-2-aminopyridin-1-ium bromide top
Crystal data top
C8H11N2+·BrF(000) = 432
Mr = 215.10Dx = 1.598 Mg m3
Orthorhombic, Pna21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2nCell parameters from 1211 reflections
a = 7.8205 (2) Åθ = 2.9–27.5°
b = 13.3560 (3) ŵ = 4.53 mm1
c = 8.5621 (2) ÅT = 120 K
V = 894.32 (4) Å3Plate, colourless
Z = 40.30 × 0.14 × 0.03 mm
Data collection top
Bruker–Nonius 95mm CCD camera on κ-goniostat
diffractometer
2033 independent reflections
Radiation source: Bruker-Nonius FR591 rotating anode1960 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.058
Detector resolution: 9.091 pixels mm-1θmax = 27.5°, θmin = 3.0°
ϕ and ω scansh = 1010
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
k = 1717
Tmin = 0.343, Tmax = 0.876l = 1011
14540 measured reflections
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.023 w = 1/[σ2(Fo2) + (0.0198P)2 + 0.704P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.053(Δ/σ)max = 0.001
S = 1.06Δρmax = 0.43 e Å3
2033 reflectionsΔρmin = 0.35 e Å3
110 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
3 restraintsExtinction coefficient: 0.0051 (7)
Primary atom site location: structure-invariant direct methodsAbsolute structure: Flack (1983), 945 Friedel pairs
Secondary atom site location: difference Fourier mapAbsolute structure parameter: 0.247 (12)
Crystal data top
C8H11N2+·BrV = 894.32 (4) Å3
Mr = 215.10Z = 4
Orthorhombic, Pna21Mo Kα radiation
a = 7.8205 (2) ŵ = 4.53 mm1
b = 13.3560 (3) ÅT = 120 K
c = 8.5621 (2) Å0.30 × 0.14 × 0.03 mm
Data collection top
Bruker–Nonius 95mm CCD camera on κ-goniostat
diffractometer
2033 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
1960 reflections with I > 2σ(I)
Tmin = 0.343, Tmax = 0.876Rint = 0.058
14540 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.023H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.053Δρmax = 0.43 e Å3
S = 1.06Δρmin = 0.35 e Å3
2033 reflectionsAbsolute structure: Flack (1983), 945 Friedel pairs
110 parametersAbsolute structure parameter: 0.247 (12)
3 restraints
Special details top

Experimental. The minimum and maximum absorption values stated above are those calculated in SHELXL97 from the given crystal dimensions. The ratio of minimum to maximum apparent transmission was determined experimentally as 0.611792.

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
Br10.03564 (3)0.120651 (14)0.72785 (7)0.01951 (9)
C10.2522 (4)0.6591 (2)0.6626 (3)0.0171 (6)
C20.2481 (4)0.75344 (18)0.5884 (3)0.0223 (5)
H20.28260.75980.48250.027*
C30.1942 (4)0.8354 (2)0.6696 (4)0.0238 (6)
H30.19090.89890.61980.029*
C40.1434 (4)0.8267 (2)0.8268 (4)0.0227 (6)
H40.10710.88370.88410.027*
C50.1474 (4)0.7353 (2)0.8941 (3)0.0210 (5)
H50.11210.72850.99970.025*
C60.1943 (3)0.55284 (19)0.8940 (3)0.0195 (5)
H6A0.19700.56321.00850.023*
H6B0.29620.51310.86470.023*
C70.0363 (3)0.4961 (2)0.8511 (3)0.0221 (6)
H70.07140.52670.87040.026*
C80.0379 (4)0.4061 (2)0.7883 (4)0.0264 (6)
H8A0.14370.37370.76780.032*
H8B0.06660.37360.76350.032*
N10.2010 (3)0.65157 (19)0.8142 (3)0.0174 (5)
N20.3083 (3)0.57779 (17)0.5869 (2)0.0208 (5)
H2A0.339 (5)0.524 (2)0.630 (4)0.049 (11)*
H2B0.341 (5)0.588 (3)0.494 (3)0.040 (10)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.02238 (13)0.02017 (12)0.01599 (12)0.00267 (8)0.00157 (17)0.00066 (16)
C10.0158 (12)0.0185 (14)0.0168 (12)0.0021 (11)0.0001 (10)0.0016 (10)
C20.0245 (13)0.0228 (14)0.0196 (13)0.0015 (11)0.0013 (11)0.0045 (10)
C30.0259 (15)0.0163 (13)0.0293 (15)0.0019 (12)0.0013 (11)0.0036 (10)
C40.0223 (14)0.0220 (14)0.0238 (15)0.0013 (11)0.0000 (11)0.0053 (11)
C50.0225 (14)0.0230 (14)0.0176 (12)0.0010 (11)0.0009 (11)0.0037 (10)
C60.0255 (13)0.0198 (12)0.0131 (11)0.0014 (10)0.0020 (10)0.0024 (9)
C70.0196 (13)0.0238 (14)0.0228 (14)0.0012 (10)0.0014 (10)0.0097 (11)
C80.0240 (14)0.0286 (14)0.0265 (13)0.0040 (11)0.0018 (10)0.0051 (12)
N10.0211 (12)0.0169 (11)0.0141 (11)0.0002 (10)0.0004 (10)0.0004 (9)
N20.0265 (12)0.0215 (12)0.0144 (11)0.0023 (9)0.0006 (9)0.0014 (9)
Geometric parameters (Å, º) top
C1—N21.339 (4)C6—N11.486 (3)
C1—N11.361 (3)C6—C71.496 (4)
C1—C21.412 (4)C6—H6A0.9900
C2—C31.364 (4)C6—H6B0.9900
C2—H20.9500C7—C81.317 (4)
C3—C41.408 (4)C7—H70.9500
C3—H30.9500C8—H8A0.9500
C4—C51.350 (4)C8—H8B0.9500
C4—H40.9500N2—H2A0.844 (18)
C5—N11.376 (4)N2—H2B0.849 (19)
C5—H50.9500
N2—C1—N1119.9 (3)C7—C6—H6A109.3
N2—C1—C2120.9 (3)N1—C6—H6B109.3
N1—C1—C2119.2 (3)C7—C6—H6B109.3
C3—C2—C1119.6 (3)H6A—C6—H6B108.0
C3—C2—H2120.2C8—C7—C6123.7 (3)
C1—C2—H2120.2C8—C7—H7118.2
C2—C3—C4120.5 (3)C6—C7—H7118.2
C2—C3—H3119.7C7—C8—H8A120.0
C4—C3—H3119.7C7—C8—H8B120.0
C5—C4—C3118.4 (3)H8A—C8—H8B120.0
C5—C4—H4120.8C1—N1—C5120.2 (3)
C3—C4—H4120.8C1—N1—C6120.9 (3)
C4—C5—N1122.0 (3)C5—N1—C6118.8 (2)
C4—C5—H5119.0C1—N2—H2A125 (3)
N1—C5—H5119.0C1—N2—H2B115 (3)
N1—C6—C7111.5 (2)H2A—N2—H2B118 (4)
N1—C6—H6A109.3
N2—C1—C2—C3178.4 (3)C2—C1—N1—C50.5 (4)
N1—C1—C2—C30.4 (4)N2—C1—N1—C64.5 (4)
C1—C2—C3—C40.2 (4)C2—C1—N1—C6176.6 (3)
C2—C3—C4—C50.8 (4)C4—C5—N1—C10.0 (4)
C3—C4—C5—N10.7 (4)C4—C5—N1—C6177.2 (3)
N1—C6—C7—C8122.7 (3)C7—C6—N1—C179.8 (3)
N2—C1—N1—C5178.3 (3)C7—C6—N1—C597.4 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···Br1i0.84 (2)2.61 (2)3.412 (2)160 (4)
N2—H2B···Br1ii0.85 (2)2.51 (2)3.357 (2)175 (3)
C6—H6A···Br1iii0.992.913.668 (3)134
C6—H6B···Br1i0.992.843.810 (3)167
Symmetry codes: (i) x+1/2, y+1/2, z; (ii) x+1/2, y+1/2, z1/2; (iii) x+1/2, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC8H11N2+·Br
Mr215.10
Crystal system, space groupOrthorhombic, Pna21
Temperature (K)120
a, b, c (Å)7.8205 (2), 13.3560 (3), 8.5621 (2)
V3)894.32 (4)
Z4
Radiation typeMo Kα
µ (mm1)4.53
Crystal size (mm)0.30 × 0.14 × 0.03
Data collection
DiffractometerBruker–Nonius 95mm CCD camera on κ-goniostat
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2003)
Tmin, Tmax0.343, 0.876
No. of measured, independent and
observed [I > 2σ(I)] reflections
14540, 2033, 1960
Rint0.058
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.023, 0.053, 1.06
No. of reflections2033
No. of parameters110
No. of restraints3
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.43, 0.35
Absolute structureFlack (1983), 945 Friedel pairs
Absolute structure parameter0.247 (12)

Computer programs: COLLECT (Nonius, 1998), DENZO (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···Br1i0.844 (18)2.61 (2)3.412 (2)160 (4)
N2—H2B···Br1ii0.849 (19)2.511 (19)3.357 (2)175 (3)
C6—H6A···Br1iii0.992.913.668 (3)133.6
C6—H6B···Br1i0.992.843.810 (3)166.5
Symmetry codes: (i) x+1/2, y+1/2, z; (ii) x+1/2, y+1/2, z1/2; (iii) x+1/2, y+1/2, z+1/2.
 

Acknowledgements

The authors thank the EPSRC National Crystallography Service (University of Southampton, UK) for the X-ray data collection and Professor P. Kaliannan for his help. ST thanks the management of SASTRA University for their encouragement.

References

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