2-Oxo-2,3-dihydro-1H-imidazo[1,2-a]pyridinium iodide.

In the title compound, C(7)H(7)N(2)O(+)·I(-), the carbonyl C and O atoms of the cation and the iodide ion are situated on mirror planes. The mean plane of the imidazo[1,2-d]pyridinium cation is perpendicular to the mirror plane as a consequence of the disorder of the cation over two opposite orientations of equal occupancy. In the crystal, N-H⋯I interactions are present.

Related literature

For the synthesis of imidazo[1,2-a]pyridinium chloride or bromide, see: Newton et al. (1984 ▶); Baumann et al. (1986 ▶). For the derivatization of imidazo[1,2-a]pyridinium and related structures, see: Plutecka et al. (2006 ▶); Hoffmann et al. (2005 ▶); Qiao et al. (2006 ▶).

Experimental

Crystal data

C7H7N2O+·I−

M = 262.05

Orthorhombic,

a = 14.597 (2) Å

b = 8.2044 (18) Å

c = 7.0926 (15) Å

V = 849.4 (3) Å3

Z = 4

Mo Kα radiation

μ = 3.71 mm−1

T = 298 K

0.48 × 0.45 × 0.23 mm

Data collection

Bruker SMART 1000 CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2001 ▶) T min = 0.269, T max = 0.482

3631 measured reflections

806 independent reflections

691 reflections with I > 2σ(I)

R int = 0.064

Refinement

R[F 2 > 2σ(F 2)] = 0.036

wR(F 2) = 0.103

S = 1.05

806 reflections

73 parameters

24 restraints

H-atom parameters constrained

Δρmax = 0.70 e Å−3

Δρmin = −0.93 e Å−3

Data collection: SMART (Bruker, 2001 ▶); cell refinement: SAINT (Bruker, 2001 ▶); data reduction: SAINT; 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.

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810004976/cv2672sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810004976/cv2672Isup2.hkl

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

C7H7N2O+·I−	Dx = 2.049 Mg m−3
Mr = 262.05	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pnma	Cell parameters from 1914 reflections
a = 14.597 (2) Å	θ = 2.5–27.2°
b = 8.2044 (18) Å	µ = 3.71 mm−1
c = 7.0926 (15) Å	T = 298 K
V = 849.4 (3) Å3	Block, red
Z = 4	0.48 × 0.45 × 0.23 mm
F(000) = 496

Bruker SMART 1000 CCD area-detector diffractometer	806 independent reflections
Radiation source: fine-focus sealed tube	691 reflections with I > 2σ(I)
graphite	Rint = 0.064
ω scans	θmax = 25.0°, θmin = 2.8°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −17→13
Tmin = 0.269, Tmax = 0.482	k = −9→9
3631 measured reflections	l = −5→8

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)] = 0.036	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.103	H-atom parameters constrained
S = 1.05	w = 1/[σ2(Fo2) + (0.0619P)2 + 0.9786P] where P = (Fo2 + 2Fc2)/3
806 reflections	(Δ/σ)max < 0.001
73 parameters	Δρmax = 0.70 e Å−3
24 restraints	Δρmin = −0.93 e Å−3

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.

	x	y	z	Uiso*/Ueq	Occ. (<1)
I1	0.41289 (4)	0.2500	0.91066 (7)	0.0537 (3)
C4	0.1109 (3)	0.0822 (7)	0.9883 (8)	0.0519 (13)
H4	0.1112	−0.0311	0.9844	0.062*
C5	0.0758 (4)	0.1656 (8)	1.1372 (9)	0.0551 (14)
H5	0.0517	0.1091	1.2395	0.066*
O1	0.2504 (5)	0.2500	0.4103 (7)	0.0724 (19)
C1	0.2120 (6)	0.2500	0.5605 (11)	0.053 (2)
C2	0.184 (3)	0.103 (3)	0.674 (4)	0.050 (9)	0.50
H2A	0.1384	0.0386	0.6073	0.060*	0.50
H2B	0.2363	0.0342	0.7024	0.060*	0.50
N2	0.146 (4)	0.174 (3)	0.846 (4)	0.039 (8)	0.50
N1	0.186 (2)	0.1164 (19)	0.666 (3)	0.049 (7)	0.50
H1	0.1935	0.0170	0.6309	0.058*	0.50
C3	0.146 (4)	0.161 (4)	0.831 (5)	0.037 (8)	0.50

	U11	U22	U33	U12	U13	U23
I1	0.0550 (4)	0.0434 (4)	0.0627 (4)	0.000	−0.0103 (2)	0.000
C4	0.044 (3)	0.044 (3)	0.068 (3)	0.002 (2)	−0.003 (3)	0.009 (3)
C5	0.046 (3)	0.064 (4)	0.056 (3)	0.000 (2)	−0.001 (2)	0.013 (3)
O1	0.070 (4)	0.099 (5)	0.049 (3)	0.000	0.003 (3)	0.000
C1	0.047 (5)	0.058 (5)	0.053 (5)	0.000	−0.004 (4)	0.000
C2	0.054 (13)	0.039 (10)	0.057 (12)	−0.006 (8)	0.009 (8)	0.005 (8)
N2	0.032 (10)	0.040 (9)	0.047 (9)	0.004 (7)	−0.003 (7)	−0.002 (6)
N1	0.047 (11)	0.042 (9)	0.058 (11)	0.003 (8)	−0.016 (8)	−0.019 (7)
C3	0.030 (11)	0.034 (10)	0.048 (10)	−0.002 (6)	−0.010 (7)	−0.006 (6)

C4—N2	1.357 (9)	C1—N1i	1.381 (9)
C4—C5	1.358 (9)	C1—C2	1.509 (10)
C4—C3	1.387 (9)	C1—C2i	1.509 (10)
C4—H4	0.9300	C2—N2	1.461 (10)
C5—C5i	1.386 (14)	C2—H2A	0.9700
C5—H5	0.9300	C2—H2B	0.9700
O1—C1	1.204 (9)	N1—C3	1.360 (10)
C1—N1	1.381 (9)	N1—H1	0.8600
N2—C4—C5	116.2 (14)	O1—C1—C2i	126.8 (12)
N2—C4—C3	6(3)	N1—C1—C2i	105.8 (7)
C5—C4—C3	121.9 (16)	N1i—C1—C2i	1(3)
N2—C4—H4	121.9	C2—C1—C2i	106 (2)
C5—C4—H4	121.9	N2—C2—C1	103.3 (11)
C3—C4—H4	116.2	N2—C2—H2A	111.1
C4—C5—C5i	120.2 (4)	C1—C2—H2A	111.1
C4—C5—H5	119.9	N2—C2—H2B	111.1
C5i—C5—H5	119.9	C1—C2—H2B	111.1
O1—C1—N1	127.5 (10)	H2A—C2—H2B	109.1
O1—C1—N1i	127.5 (10)	C4—N2—C2	122.9 (19)
N1—C1—N1i	105 (2)	C3—N1—C1	111.7 (10)
O1—C1—C2	126.8 (12)	C3—N1—H1	124.1
N1—C1—C2	1(3)	C1—N1—H1	124.1
N1i—C1—C2	105.8 (7)	N1—C3—C4	136 (2)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H2A···I1ii	1.03	2.85	3.80 (2)	153

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H2A⋯I1i	1.03	2.85	3.80 (2)	153

Symmetry code: (i) .