2,3-Diphenyl­quinoxalin-1-ium chloride

Wu, W.-S.

doi:10.1107/S1600536810023883

organic compounds

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ISSN: 2056-9890

Volume 66| Part 7| July 2010| Page o1807

doi:10.1107/S1600536810023883

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2,3-Diphenylquinoxalin-1-ium chloride

Wen-Sheng Wu ^a ^*

^aSchool of Chemistry and Chemical Engineering, Zhaoqing University, Zhaoqing 526061, People's Republic of China
^*Correspondence e-mail: wswu2002@126.com

(Received 14 June 2010; accepted 20 June 2010; online 26 June 2010)

The title compound, C₂₀H₁₅N₂⁺·Cl⁻, was prepared by the reaction of benzil with o-phenylenediamine in refluxing ethanol and then crystallized in 5% hydrochloric acid. The two phenyl rings are oriented at dihedral angles of 50.93 (8) and 50.28 (8)° with respect to the quinoxalin-1-ium ring system. The dihedral angle between the two phenyl rings is 56.71 (10)°. In the crystal, the cations and anions are linked by N—H⋯Cl and C—H⋯Cl interactions, forming chains along the b axis.

Related literature

For general background to quinoxaline derivatives, see: Brock et al. (1999 ); Dailey et al. (2001 ); Page et al. (1998 ); Pascal et al. (1993 ). For a related structure, see: Wu et al. (2002 ).

Experimental

Crystal data

C₂₀H₁₅N₂⁺·Cl⁻
M_r = 318.79
Monoclinic, P 2₁ /c
a = 10.498 (3) Å
b = 14.773 (5) Å
c = 11.359 (4) Å
β = 112.692 (3)°
V = 1625.3 (9) Å³
Z = 4
Mo Kα radiation
μ = 0.24 mm⁻¹
T = 293 K
0.25 × 0.22 × 0.20 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2002 ) T_min = 0.943, T_max = 0.954
9558 measured reflections
2893 independent reflections
2257 reflections with I > 2σ(I)
R_int = 0.034

Refinement

R[F² > 2σ(F²)] = 0.039
wR(F²) = 0.109
S = 1.06
2893 reflections
209 parameters
H-atom parameters constrained
Δρ_max = 0.18 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯Cl1ⁱ	0.86	2.14	2.9684 (16)	160
C18—H18⋯Cl1	0.93	2.73	3.568 (2)	150
Symmetry code: (i) $[-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810023883/ci5102sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810023883/ci5102Isup2.hkl

checkCIF report

Comment top

Quinoxaline and its derivatives have received considerable attention in the past several years due to their electronic properties (Page et al., 1998), H-bonding ability (Pascal et al., 1993), and their capacity to coordinate to metals and forming interesting three-dimensional structures (Wu et al., 2002). Quinoxaline derivatives are also an important class of nitrogen containing heterocycles and constitute useful intermediates in organic synthesis which have been reported for their applications in the field of dyes (Brock et al., 1999) and have also been used as building blocks for the synthesis of organic semiconductors (Dailey et al., 2001). The title compound was synthesized as part of our study of these ligands.

The quinoxalin-1-ium ring system (N1/N2/C13-C20) is planar within ±0.035 (2) Å. The C1–C6 and C7–C12 phenyl rings form dihedral angles of 50.93 (8)° and 50.28 (8)°, respectively, with the quinoxalin-1-ium ring system. The dihedral angle between the two phenyl rings is 56.71 (10)°.

The N1—H1A···Cl1 and C18—H18···Cl1 hydrogen bonds are present in the crystal structure (Table 1), and these hydrogen bonds link the molecules into a chain along the b axis.

Related literature top

For general background to quinoxaline derivatives, see: Brock et al. (1999); Dailey et al. (2001); Page et al. (1998); Pascal et al. (1993). For a related structure, see: Wu et al. (2002).

Experimental top

A 100 ml round-bottomed flask was charged with benzil (10.5 g, 0.05 mol), o-phenylenediamine (5.4 g, 0.05 mol) and ethanol (50 ml). The mixture was refluxed, and the reaction was monitored by thin-layer chromatography until complete consumption of the starting materials (4 h). The resulting solution was concentrated to dryness under reduced pressure. The dark-brown crude product was dissolved in methanol (30 ml). The solution was filtered and the filtrate was dissolved in 5% hydrochloric acid (30 ml) and set aside for three weeks to obtain yellow crystals.

Computing details top

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

Fig. 1. The asymmetric unit of the title compound, showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level.

2,3-Diphenylquinoxalin-1-ium chloride top

Crystal data top

C₂₀H₁₅N₂⁺·Cl⁻	F(000) = 664
M_r = 318.79	D_x = 1.303 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2838 reflections
a = 10.498 (3) Å	θ = 2.1–25.1°
b = 14.773 (5) Å	µ = 0.24 mm⁻¹
c = 11.359 (4) Å	T = 293 K
β = 112.692 (3)°	Block, yellow
V = 1625.3 (9) Å³	0.25 × 0.22 × 0.20 mm
Z = 4

Data collection top

Bruker SMART CCD area-detector diffractometer	2893 independent reflections
Radiation source: fine-focus sealed tube	2257 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.034
ϕ and ω scans	θ_max = 25.1°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2002)	h = −12→12
T_min = 0.943, T_max = 0.954	k = −17→17
9558 measured reflections	l = −13→10

Refinement top

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)] = 0.039	H-atom parameters constrained
wR(F²) = 0.109	w = 1/[σ²(F_o²) + (0.0549P)² + 0.2666P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max = 0.001
2893 reflections	Δρ_max = 0.18 e Å⁻³
209 parameters	Δρ_min = −0.24 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.068 (4)

Crystal data top

C₂₀H₁₅N₂⁺·Cl⁻	V = 1625.3 (9) Å³
M_r = 318.79	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 10.498 (3) Å	µ = 0.24 mm⁻¹
b = 14.773 (5) Å	T = 293 K
c = 11.359 (4) Å	0.25 × 0.22 × 0.20 mm
β = 112.692 (3)°

Data collection top

Bruker SMART CCD area-detector diffractometer	2893 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2002)	2257 reflections with I > 2σ(I)
T_min = 0.943, T_max = 0.954	R_int = 0.034
9558 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.039	0 restraints
wR(F²) = 0.109	H-atom parameters constrained
S = 1.06	Δρ_max = 0.18 e Å⁻³
2893 reflections	Δρ_min = −0.24 e Å⁻³
209 parameters

Special details top

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

	x	y	z	U_iso*/U_eq
Cl1	−0.00715 (5)	0.21487 (3)	0.19706 (5)	0.0593 (2)
C13	0.25287 (17)	0.73467 (11)	0.12361 (16)	0.0396 (4)
C6	0.23732 (18)	0.83023 (11)	0.15477 (17)	0.0410 (4)
C14	0.35118 (18)	0.70084 (11)	0.07464 (17)	0.0420 (4)
C1	0.35195 (19)	0.88047 (12)	0.22987 (19)	0.0497 (5)
H1	0.4398	0.8553	0.2571	0.060*
C12	0.44507 (19)	0.76230 (12)	0.04193 (17)	0.0442 (4)
C20	0.18022 (19)	0.58334 (11)	0.13075 (17)	0.0456 (4)
C8	0.6742 (2)	0.79882 (16)	0.0578 (2)	0.0698 (6)
H8	0.7683	0.7863	0.0901	0.084*
C5	0.10701 (19)	0.86889 (12)	0.11425 (18)	0.0483 (5)
H5	0.0297	0.8355	0.0649	0.058*
C2	0.3345 (2)	0.96830 (13)	0.2638 (2)	0.0593 (5)
H2	0.4108	1.0016	0.3154	0.071*
C15	0.2795 (2)	0.55363 (12)	0.08495 (17)	0.0483 (5)
C4	0.0922 (2)	0.95729 (13)	0.14748 (19)	0.0544 (5)
H4	0.0048	0.9834	0.1190	0.065*
C3	0.2050 (2)	1.00672 (13)	0.2220 (2)	0.0586 (6)
H3	0.1941	1.0660	0.2442	0.070*
C18	0.1142 (2)	0.43199 (14)	0.1498 (2)	0.0664 (6)
H18	0.0618	0.3905	0.1734	0.080*
C7	0.5854 (2)	0.74393 (14)	0.0890 (2)	0.0578 (5)
H7	0.6200	0.6942	0.1421	0.069*
C17	0.2095 (3)	0.40062 (13)	0.1005 (2)	0.0677 (6)
H17	0.2171	0.3388	0.0895	0.081*
C11	0.3943 (2)	0.83694 (13)	−0.03710 (18)	0.0508 (5)
H11	0.3006	0.8505	−0.0680	0.061*
C19	0.0969 (2)	0.52241 (13)	0.16366 (19)	0.0564 (5)
H19	0.0317	0.5430	0.1941	0.068*
C16	0.2915 (2)	0.45917 (13)	0.0684 (2)	0.0604 (6)
H16	0.3545	0.4374	0.0360	0.072*
C10	0.4835 (2)	0.89082 (15)	−0.0695 (2)	0.0642 (6)
H10	0.4493	0.9398	−0.1240	0.077*
C9	0.6229 (2)	0.87214 (17)	−0.0213 (2)	0.0733 (7)
H9	0.6827	0.9092	−0.0422	0.088*
N1	0.17297 (15)	0.67478 (9)	0.14856 (14)	0.0431 (4)
H1A	0.1134	0.6942	0.1774	0.052*
N2	0.36430 (16)	0.61318 (10)	0.05822 (15)	0.0489 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0709 (4)	0.0488 (3)	0.0721 (4)	−0.0091 (2)	0.0429 (3)	−0.0097 (2)
C13	0.0447 (9)	0.0376 (9)	0.0363 (10)	0.0010 (7)	0.0152 (8)	0.0010 (7)
C6	0.0522 (10)	0.0352 (9)	0.0420 (10)	0.0013 (8)	0.0251 (8)	0.0027 (8)
C14	0.0503 (10)	0.0391 (9)	0.0378 (10)	0.0026 (8)	0.0183 (8)	−0.0010 (7)
C1	0.0525 (11)	0.0440 (10)	0.0567 (12)	0.0004 (8)	0.0256 (9)	−0.0038 (9)
C12	0.0537 (11)	0.0414 (9)	0.0436 (11)	0.0014 (8)	0.0257 (9)	−0.0053 (8)
C20	0.0562 (11)	0.0367 (9)	0.0413 (10)	−0.0013 (8)	0.0162 (9)	−0.0007 (8)
C8	0.0539 (12)	0.0829 (16)	0.0802 (16)	0.0013 (11)	0.0342 (12)	0.0017 (13)
C5	0.0530 (11)	0.0476 (10)	0.0475 (11)	0.0025 (8)	0.0230 (9)	0.0024 (8)
C2	0.0686 (13)	0.0436 (10)	0.0722 (15)	−0.0085 (10)	0.0343 (12)	−0.0121 (10)
C15	0.0598 (11)	0.0384 (9)	0.0449 (11)	0.0005 (8)	0.0183 (9)	−0.0008 (8)
C4	0.0653 (13)	0.0503 (11)	0.0570 (12)	0.0179 (10)	0.0339 (11)	0.0089 (10)
C3	0.0823 (15)	0.0378 (10)	0.0691 (14)	0.0048 (10)	0.0441 (12)	−0.0011 (9)
C18	0.0847 (16)	0.0457 (11)	0.0668 (14)	−0.0142 (11)	0.0272 (12)	0.0036 (10)
C7	0.0577 (12)	0.0540 (11)	0.0684 (14)	0.0113 (10)	0.0317 (11)	0.0039 (10)
C17	0.0913 (16)	0.0349 (10)	0.0705 (15)	−0.0045 (11)	0.0242 (13)	−0.0022 (10)
C11	0.0544 (11)	0.0532 (11)	0.0456 (11)	−0.0004 (9)	0.0201 (9)	0.0025 (9)
C19	0.0684 (13)	0.0457 (11)	0.0567 (13)	−0.0071 (9)	0.0261 (10)	0.0020 (9)
C16	0.0754 (14)	0.0397 (10)	0.0624 (13)	0.0030 (10)	0.0225 (11)	−0.0066 (9)
C10	0.0742 (15)	0.0642 (13)	0.0553 (13)	−0.0057 (11)	0.0264 (11)	0.0136 (11)
C9	0.0718 (15)	0.0853 (16)	0.0735 (16)	−0.0172 (13)	0.0398 (13)	0.0062 (13)
N1	0.0508 (9)	0.0383 (8)	0.0444 (9)	0.0024 (7)	0.0230 (7)	0.0014 (7)
N2	0.0590 (9)	0.0388 (8)	0.0508 (10)	0.0033 (7)	0.0234 (8)	−0.0024 (7)

Geometric parameters (Å, º) top

C13—N1	1.323 (2)	C2—H2	0.93
C13—C14	1.438 (2)	C15—N2	1.367 (2)
C13—C6	1.480 (2)	C15—C16	1.420 (3)
C6—C5	1.387 (2)	C4—C3	1.371 (3)
C6—C1	1.391 (3)	C4—H4	0.93
C14—N2	1.323 (2)	C3—H3	0.93
C14—C12	1.489 (2)	C18—C19	1.365 (3)
C1—C2	1.386 (3)	C18—C17	1.400 (3)
C1—H1	0.93	C18—H18	0.93
C12—C7	1.387 (3)	C7—H7	0.93
C12—C11	1.392 (3)	C17—C16	1.366 (3)
C20—N1	1.372 (2)	C17—H17	0.93
C20—C19	1.402 (3)	C11—C10	1.383 (3)
C20—C15	1.403 (2)	C11—H11	0.93
C8—C9	1.377 (3)	C19—H19	0.93
C8—C7	1.381 (3)	C16—H16	0.93
C8—H8	0.93	C10—C9	1.379 (3)
C5—C4	1.385 (3)	C10—H10	0.93
C5—H5	0.93	C9—H9	0.93
C2—C3	1.378 (3)	N1—H1A	0.86

N1—C13—C14	117.35 (15)	C5—C4—H4	119.7
N1—C13—C6	116.70 (15)	C4—C3—C2	119.74 (18)
C14—C13—C6	125.88 (15)	C4—C3—H3	120.1
C5—C6—C1	119.53 (16)	C2—C3—H3	120.1
C5—C6—C13	119.95 (16)	C19—C18—C17	121.2 (2)
C1—C6—C13	120.44 (16)	C19—C18—H18	119.4
N2—C14—C13	121.60 (16)	C17—C18—H18	119.4
N2—C14—C12	116.54 (15)	C8—C7—C12	120.5 (2)
C13—C14—C12	121.85 (14)	C8—C7—H7	119.7
C2—C1—C6	119.62 (18)	C12—C7—H7	119.7
C2—C1—H1	120.2	C16—C17—C18	121.22 (19)
C6—C1—H1	120.2	C16—C17—H17	119.4
C7—C12—C11	119.33 (18)	C18—C17—H17	119.4
C7—C12—C14	119.44 (17)	C10—C11—C12	119.84 (18)
C11—C12—C14	121.22 (16)	C10—C11—H11	120.1
N1—C20—C19	121.12 (17)	C12—C11—H11	120.1
N1—C20—C15	117.01 (15)	C18—C19—C20	118.2 (2)
C19—C20—C15	121.79 (16)	C18—C19—H19	120.9
C9—C8—C7	119.8 (2)	C20—C19—H19	120.9
C9—C8—H8	120.1	C17—C16—C15	119.3 (2)
C7—C8—H8	120.1	C17—C16—H16	120.3
C4—C5—C6	119.88 (18)	C15—C16—H16	120.3
C4—C5—H5	120.1	C9—C10—C11	120.2 (2)
C6—C5—H5	120.1	C9—C10—H10	119.9
C3—C2—C1	120.58 (19)	C11—C10—H10	119.9
C3—C2—H2	119.7	C8—C9—C10	120.3 (2)
C1—C2—H2	119.7	C8—C9—H9	119.9
N2—C15—C20	121.46 (16)	C10—C9—H9	119.9
N2—C15—C16	120.29 (18)	C13—N1—C20	123.43 (15)
C20—C15—C16	118.24 (17)	C13—N1—H1A	118.3
C3—C4—C5	120.63 (18)	C20—N1—H1A	118.3
C3—C4—H4	119.7	C14—N2—C15	119.11 (16)

N1—C13—C6—C5	−49.4 (2)	C9—C8—C7—C12	−0.4 (3)
C14—C13—C6—C5	133.74 (19)	C11—C12—C7—C8	−0.2 (3)
N1—C13—C6—C1	127.41 (18)	C14—C12—C7—C8	178.61 (19)
C14—C13—C6—C1	−49.4 (3)	C19—C18—C17—C16	2.1 (3)
N1—C13—C14—N2	−1.8 (3)	C7—C12—C11—C10	1.1 (3)
C6—C13—C14—N2	175.02 (17)	C14—C12—C11—C10	−177.61 (18)
N1—C13—C14—C12	179.30 (16)	C17—C18—C19—C20	−1.9 (3)
C6—C13—C14—C12	−3.9 (3)	N1—C20—C19—C18	−176.65 (19)
C5—C6—C1—C2	0.4 (3)	C15—C20—C19—C18	−0.2 (3)
C13—C6—C1—C2	−176.49 (17)	C18—C17—C16—C15	−0.2 (3)
N2—C14—C12—C7	−49.1 (2)	N2—C15—C16—C17	177.39 (19)
C13—C14—C12—C7	129.83 (19)	C20—C15—C16—C17	−1.8 (3)
N2—C14—C12—C11	129.61 (18)	C12—C11—C10—C9	−1.6 (3)
C13—C14—C12—C11	−51.4 (2)	C7—C8—C9—C10	−0.1 (4)
C1—C6—C5—C4	0.8 (3)	C11—C10—C9—C8	1.1 (4)
C13—C6—C5—C4	177.62 (16)	C14—C13—N1—C20	0.4 (2)
C6—C1—C2—C3	−1.2 (3)	C6—C13—N1—C20	−176.73 (16)
N1—C20—C15—N2	−0.6 (3)	C19—C20—N1—C13	177.36 (17)
C19—C20—C15—N2	−177.17 (17)	C15—C20—N1—C13	0.7 (3)
N1—C20—C15—C16	178.58 (17)	C13—C14—N2—C15	2.0 (3)
C19—C20—C15—C16	2.0 (3)	C12—C14—N2—C15	−179.07 (15)
C6—C5—C4—C3	−1.1 (3)	C20—C15—N2—C14	−0.8 (3)
C5—C4—C3—C2	0.3 (3)	C16—C15—N2—C14	−179.90 (18)
C1—C2—C3—C4	0.9 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···Cl1ⁱ	0.86	2.14	2.9684 (16)	160
C18—H18···Cl1	0.93	2.73	3.568 (2)	150

Symmetry code: (i) −x, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formula	C₂₀H₁₅N₂⁺·Cl⁻
M_r	318.79
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	10.498 (3), 14.773 (5), 11.359 (4)
β (°)	112.692 (3)
V (Å³)	1625.3 (9)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.24
Crystal size (mm)	0.25 × 0.22 × 0.20

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2002)
T_min, T_max	0.943, 0.954
No. of measured, independent and observed [I > 2σ(I)] reflections	9558, 2893, 2257
R_int	0.034
(sin θ/λ)_max (Å⁻¹)	0.596

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.039, 0.109, 1.06
No. of reflections	2893
No. of parameters	209
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.18, −0.24

Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···Cl1ⁱ	0.86	2.14	2.9684 (16)	160
C18—H18···Cl1	0.93	2.73	3.568 (2)	150

Symmetry code: (i) −x, y+1/2, −z+1/2.

Acknowledgements

The author gratefully acknowledges the Natural Science Foundation of Guangdong Province of China (No. 8452606101000739) and the Natural Science Foundation of Zhaoqing University (No. 0933) for financial support.

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