4-Meth-oxy-benzamidinium bromide.

The title salt, C8H11N2O(+)·Br(-), was synthesized by the reaction between 4-meth-oxy-benzamidine (4-amidino-anisole) and hydro-bromic acid. In the cation, the amidinium group has two similar C-N bonds [1.304 (2) and 1.316 (2) Å], and its plane forms a dihedral angle of 31.08 (5)° with the benzene ring. The ions are associated in the crystal into a three-dimension hydrogen-bonded supra-molecular network featuring N-H(+)⋯Br(-) inter-actions.

Related literature

For the biological and pharmacological relevance of benzamidine, see: Powers & Harper (1999 ▶). For structural analysis of proton-transfer adducts containing mol­ecules of biological inter­est, see: Portalone (2011 ▶); Portalone & Irrera (2011 ▶). For the supra­molecular association in proton-transfer adducts containing benzamidinium cations, see: Portalone (2010 ▶, 2012 ▶); Irrera et al. (2012 ▶); Irrera & Portalone (2012a ▶,b ▶,c ▶,d ▶,e ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶).

Experimental

Crystal data

C8H11N2O+·Br−

M = 231.10

Orthorhombic,

a = 7.5657 (6) Å

b = 10.8711 (7) Å

c = 11.5419 (7) Å

V = 949.29 (11) Å3

Z = 4

Mo Kα radiation

μ = 4.29 mm−1

T = 298 K

0.18 × 0.12 × 0.10 mm

Data collection

Agilent Xcalibur Sapphire3 diffractometer

Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011 ▶) T min = 0.513, T max = 0.674

34724 measured reflections

3278 independent reflections

2903 reflections with I > 2σ(I)

R int = 0.043

Refinement

R[F 2 > 2σ(F 2)] = 0.027

wR(F 2) = 0.055

S = 1.09

3278 reflections

126 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.22 e Å−3

Δρmin = −0.31 e Å−3

Absolute structure: Flack (1983 ▶), 1387 Friedel pairs

Flack parameter: −0.002 (9)

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 ▶); cell refinement: CrysAlis RED (Oxford Diffraction, 2006 ▶); data reduction: CrysAlis RED; program(s) used to solve structure: SIR97 (Altomare et al., 1999 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: WinGX (Farrugia, 2012 ▶); software used to prepare material for publication: WinGX (Farrugia, 2012 ▶).

Click here for additional data file.

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536812049872/rz5032sup1.cif

Click here for additional data file.

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812049872/rz5032Isup2.hkl

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

C8H11N2O+·Br−	F(000) = 464
Mr = 231.10	Dx = 1.617 Mg m−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: P 2ac 2ab	Cell parameters from 10829 reflections
a = 7.5657 (6) Å	θ = 3.2–32.5°
b = 10.8711 (7) Å	µ = 4.29 mm−1
c = 11.5419 (7) Å	T = 298 K
V = 949.29 (11) Å3	Tablets, colourless
Z = 4	0.18 × 0.12 × 0.10 mm

Agilent Xcalibur Sapphire3 diffractometer	3278 independent reflections
Radiation source: Enhance (Mo) X-ray Source	2903 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.043
Detector resolution: 16.0696 pixels mm-1	θmax = 32.0°, θmin = 3.2°
ω and φ scans	h = −11→11
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011)	k = −16→16
Tmin = 0.513, Tmax = 0.674	l = −17→17
34724 measured reflections

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.027	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.055	w = 1/[σ2(Fo2) + (0.0236P)2 + 0.1235P] where P = (Fo2 + 2Fc2)/3
S = 1.09	(Δ/σ)max < 0.001
3278 reflections	Δρmax = 0.22 e Å−3
126 parameters	Δρmin = −0.31 e Å−3
0 restraints	Absolute structure: Flack (1983), 1387 Friedel pairs
Primary atom site location: structure-invariant direct methods	Flack parameter: −0.002 (9)

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 > 2σ(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.

	x	y	z	Uiso*/Ueq
Br1	0.35106 (3)	0.611694 (17)	−0.195955 (16)	0.04325 (6)
O1	0.3480 (2)	−0.16213 (12)	0.17351 (11)	0.0435 (3)
N1	0.4313 (3)	0.31784 (17)	−0.13950 (15)	0.0431 (4)
H1A	0.431 (3)	0.392 (3)	−0.169 (2)	0.056 (7)*
H1B	0.484 (3)	0.261 (3)	−0.181 (2)	0.062 (8)*
N2	0.3375 (3)	0.40022 (16)	0.02982 (15)	0.0440 (4)
H2A	0.329 (3)	0.480 (2)	−0.003 (2)	0.060 (7)*
H2B	0.300 (3)	0.394 (3)	0.092 (2)	0.054 (7)*
C1	0.3765 (2)	0.18004 (16)	0.01954 (14)	0.0312 (3)
C2	0.3378 (3)	0.07914 (17)	−0.04827 (15)	0.0387 (4)
H2	0.3177	0.0898	−0.1271	0.046*
C3	0.3284 (3)	−0.03770 (17)	−0.00107 (16)	0.0407 (4)
H3	0.3034	−0.1052	−0.0477	0.049*
C4	0.3568 (3)	−0.05267 (15)	0.11722 (15)	0.0347 (3)
C5	0.3987 (2)	0.04789 (17)	0.18527 (16)	0.0383 (4)
H5	0.4210	0.0370	0.2638	0.046*
C6	0.4076 (2)	0.16333 (18)	0.13810 (16)	0.0364 (4)
H6	0.4344	0.2306	0.1848	0.044*
C7	0.3823 (2)	0.30343 (17)	−0.03201 (15)	0.0319 (4)
C8	0.3064 (3)	−0.26858 (18)	0.1078 (2)	0.0521 (6)
H8A	0.1936	−0.2578	0.0711	0.078*
H8B	0.3021	−0.3388	0.1581	0.078*
H8C	0.3955	−0.2811	0.0498	0.078*

	U11	U22	U33	U12	U13	U23
Br1	0.05673 (11)	0.03755 (9)	0.03548 (8)	−0.00280 (10)	−0.00105 (9)	0.01017 (8)
O1	0.0614 (8)	0.0328 (6)	0.0364 (7)	0.0010 (7)	−0.0039 (7)	0.0042 (5)
N1	0.0643 (11)	0.0313 (8)	0.0338 (8)	0.0052 (8)	0.0086 (8)	0.0021 (7)
N2	0.0634 (10)	0.0317 (8)	0.0368 (8)	0.0032 (10)	0.0107 (8)	−0.0013 (7)
C1	0.0340 (9)	0.0304 (8)	0.0291 (7)	0.0011 (7)	0.0007 (7)	0.0000 (6)
C2	0.0536 (11)	0.0369 (9)	0.0255 (7)	−0.0042 (9)	−0.0032 (8)	−0.0002 (6)
C3	0.0581 (13)	0.0329 (8)	0.0311 (8)	−0.0050 (9)	−0.0029 (9)	−0.0035 (7)
C4	0.0385 (8)	0.0324 (8)	0.0332 (8)	0.0036 (9)	0.0004 (9)	0.0038 (6)
C5	0.0489 (10)	0.0387 (9)	0.0272 (8)	0.0020 (7)	−0.0061 (8)	0.0017 (7)
C6	0.0459 (10)	0.0335 (9)	0.0298 (8)	0.0018 (8)	−0.0040 (7)	−0.0055 (7)
C7	0.0331 (9)	0.0312 (8)	0.0313 (8)	−0.0008 (7)	−0.0005 (7)	−0.0012 (6)
C8	0.0759 (17)	0.0332 (10)	0.0474 (11)	0.0008 (10)	0.0045 (11)	0.0001 (8)

O1—C4	1.357 (2)	C2—C3	1.384 (3)
O1—C8	1.419 (2)	C2—H2	0.9300
N1—C7	1.304 (2)	C3—C4	1.392 (2)
N1—H1A	0.87 (3)	C3—H3	0.9300
N1—H1B	0.88 (3)	C4—C5	1.383 (3)
N2—C7	1.316 (2)	C5—C6	1.370 (3)
N2—H2A	0.95 (3)	C5—H5	0.9300
N2—H2B	0.78 (2)	C6—H6	0.9300
C1—C2	1.379 (2)	C8—H8A	0.9600
C1—C6	1.400 (2)	C8—H8B	0.9600
C1—C7	1.468 (2)	C8—H8C	0.9600
C4—O1—C8	118.05 (14)	O1—C4—C3	124.37 (16)
C7—N1—H1A	118.6 (16)	C5—C4—C3	120.01 (16)
C7—N1—H1B	124.6 (17)	C6—C5—C4	120.66 (16)
H1A—N1—H1B	116 (2)	C6—C5—H5	119.7
C7—N2—H2A	122.2 (16)	C4—C5—H5	119.7
C7—N2—H2B	122 (2)	C5—C6—C1	119.93 (17)
H2A—N2—H2B	115 (3)	C5—C6—H6	120.0
C2—C1—C6	119.15 (17)	C1—C6—H6	120.0
C2—C1—C7	120.22 (15)	N1—C7—N2	119.54 (18)
C6—C1—C7	120.62 (16)	N1—C7—C1	120.25 (16)
C1—C2—C3	121.18 (16)	N2—C7—C1	120.21 (16)
C1—C2—H2	119.4	O1—C8—H8A	109.5
C3—C2—H2	119.4	O1—C8—H8B	109.5
C2—C3—C4	119.05 (16)	H8A—C8—H8B	109.5
C2—C3—H3	120.5	O1—C8—H8C	109.5
C4—C3—H3	120.5	H8A—C8—H8C	109.5
O1—C4—C5	115.62 (15)	H8B—C8—H8C	109.5
C6—C1—C2—C3	0.4 (3)	C3—C4—C5—C6	1.9 (3)
C7—C1—C2—C3	−178.8 (2)	C4—C5—C6—C1	−0.8 (3)
C1—C2—C3—C4	0.7 (3)	C2—C1—C6—C5	−0.3 (3)
C8—O1—C4—C5	−179.67 (18)	C7—C1—C6—C5	178.87 (17)
C8—O1—C4—C3	−0.2 (3)	C2—C1—C7—N1	−31.3 (3)
C2—C3—C4—O1	178.8 (2)	C6—C1—C7—N1	149.52 (19)
C2—C3—C4—C5	−1.8 (3)	C2—C1—C7—N2	148.4 (2)
O1—C4—C5—C6	−178.63 (18)	C6—C1—C7—N2	−30.7 (3)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···Br1	0.87 (3)	2.48 (3)	3.3163 (19)	159 (2)
N1—H1B···Br1i	0.88 (3)	2.49 (3)	3.3676 (19)	176 (2)
N2—H2A···Br1	0.95 (3)	2.65 (3)	3.4765 (17)	145 (2)
N2—H2B···Br1ii	0.78 (2)	2.70 (3)	3.4742 (17)	175 (2)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯Br1	0.87 (3)	2.48 (3)	3.3163 (19)	159 (2)
N1—H1B⋯Br1i	0.88 (3)	2.49 (3)	3.3676 (19)	176 (2)
N2—H2A⋯Br1	0.95 (3)	2.65 (3)	3.4765 (17)	145 (2)
N2—H2B⋯Br1ii	0.78 (2)	2.70 (3)	3.4742 (17)	175 (2)

Symmetry codes: (i) ; (ii) .