(Z)-1,2-Dichloro-1,2-bis-(3-chloro-quinoxalin-2-yl)ethene.

The title compound, C(18)H(8)Cl(4)N(4), exists in a cis configuration with respect to the bridging C=C bond. The two essentially planar quinoxaline ring systems [maximum deviations = 0.012 (1) and 0.022 (1) Å] are inclined at an angle of 59.84 (3). In the crystal, adjacent mol-ecules are linked into chains propagating along [001] via inter-molecular C-H⋯N hydrogen bonds. Weak inter-molecular π-π [centroid-centroid distance = 3.6029 (7)°] and C-H⋯π inter-actions are also observed.

Related literature

For general background to and applications of the title compound, see: Fun et al. (2009 ▶); Goswami et al. (2007 ▶). For closely related structures, see: Fun et al. (2009 ▶); Goswami et al. (2007 ▶). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 ▶).

Experimental

Crystal data

C18H8Cl4N4

M = 422.08

Monoclinic,

a = 19.0972 (5) Å

b = 10.9883 (3) Å

c = 8.1905 (2) Å

β = 90.782 (1)°

V = 1718.58 (8) Å3

Z = 4

Mo Kα radiation

μ = 0.70 mm−1

T = 100 K

0.79 × 0.22 × 0.10 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T min = 0.608, T max = 0.933

72483 measured reflections

8778 independent reflections

6556 reflections with I > 2σ(I)

R int = 0.061

Refinement

R[F 2 > 2σ(F 2)] = 0.042

wR(F 2) = 0.119

S = 1.11

8778 reflections

267 parameters

All H-atom parameters refined

Δρmax = 0.59 e Å−3

Δρmin = −0.35 e Å−3

Data collection: APEX2 (Bruker, 2009 ▶); cell refinement: SAINT (Bruker, 2009 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810054322/sj5082sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810054322/sj5082Isup2.hkl

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

C18H8Cl4N4	F(000) = 848
Mr = 422.08	Dx = 1.631 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 9887 reflections
a = 19.0972 (5) Å	θ = 2.1–37.2°
b = 10.9883 (3) Å	µ = 0.70 mm−1
c = 8.1905 (2) Å	T = 100 K
β = 90.782 (1)°	Block, yellow
V = 1718.58 (8) Å3	0.79 × 0.22 × 0.10 mm
Z = 4

Bruker SMART APEXII CCD area-detector diffractometer	8778 independent reflections
Radiation source: fine-focus sealed tube	6556 reflections with I > 2σ(I)
graphite	Rint = 0.061
φ and ω scans	θmax = 37.2°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −32→32
Tmin = 0.608, Tmax = 0.933	k = −18→18
72483 measured reflections	l = −13→13

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)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.119	All H-atom parameters refined
S = 1.11	w = 1/[σ2(Fo2) + (0.060P)2 + 0.1538P] where P = (Fo2 + 2Fc2)/3
8778 reflections	(Δ/σ)max = 0.001
267 parameters	Δρmax = 0.59 e Å−3
0 restraints	Δρmin = −0.35 e Å−3

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1)K.

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
Cl1	0.230183 (15)	0.56482 (3)	−0.19687 (4)	0.01973 (7)
Cl2	0.408666 (15)	0.33929 (3)	−0.01835 (4)	0.02087 (7)
Cl3	0.277057 (17)	0.19701 (3)	0.08651 (5)	0.02505 (8)
Cl4	0.139656 (17)	0.28579 (3)	−0.12100 (4)	0.02431 (7)
N1	0.39159 (5)	0.59732 (9)	0.11036 (12)	0.01616 (17)
N2	0.30364 (5)	0.74383 (9)	−0.08414 (12)	0.01681 (17)
N3	0.21167 (5)	0.49059 (9)	0.24250 (12)	0.01686 (17)
N4	0.08344 (5)	0.42781 (9)	0.09017 (13)	0.01902 (19)
C1	0.40036 (6)	0.72039 (10)	0.10598 (14)	0.01538 (19)
C2	0.45443 (6)	0.77568 (11)	0.20007 (15)	0.0180 (2)
C3	0.46254 (7)	0.89969 (11)	0.19571 (16)	0.0202 (2)
C4	0.41789 (7)	0.97290 (11)	0.09745 (16)	0.0205 (2)
C5	0.36555 (7)	0.92203 (10)	0.00467 (15)	0.0181 (2)
C6	0.35580 (6)	0.79460 (10)	0.00883 (14)	0.01560 (19)
C7	0.29618 (6)	0.62669 (10)	−0.07490 (14)	0.01589 (19)
C8	0.33959 (6)	0.55012 (10)	0.02467 (14)	0.01502 (18)
C9	0.33274 (6)	0.41522 (10)	0.03069 (15)	0.01644 (19)
C10	0.27542 (6)	0.35370 (10)	0.07344 (15)	0.0173 (2)
C11	0.20886 (6)	0.41146 (10)	0.12282 (14)	0.01590 (19)
C12	0.14274 (6)	0.38222 (10)	0.04606 (14)	0.0173 (2)
C13	0.08526 (6)	0.50918 (11)	0.21677 (15)	0.0181 (2)
C14	0.02225 (7)	0.56163 (13)	0.26997 (17)	0.0240 (2)
C15	0.02406 (8)	0.64421 (14)	0.39522 (19)	0.0281 (3)
C16	0.08807 (8)	0.67632 (13)	0.47183 (19)	0.0275 (3)
C17	0.15010 (7)	0.62649 (12)	0.42128 (16)	0.0230 (2)
C18	0.14972 (6)	0.54162 (10)	0.29197 (14)	0.01708 (19)
H2	0.4818 (9)	0.7241 (16)	0.265 (2)	0.026 (4)*
H3	0.4954 (10)	0.9394 (17)	0.253 (2)	0.039 (5)*
H4	0.4232 (9)	1.0550 (17)	0.094 (2)	0.028 (5)*
H5	0.3373 (9)	0.9670 (16)	−0.066 (2)	0.027 (4)*
H14	−0.0216 (9)	0.5407 (16)	0.215 (2)	0.030 (5)*
H15	−0.0164 (12)	0.6781 (18)	0.435 (3)	0.041 (6)*
H16	0.0870 (10)	0.7361 (18)	0.559 (3)	0.035 (5)*
H17	0.1949 (9)	0.6476 (16)	0.478 (2)	0.026 (4)*

	U11	U22	U33	U12	U13	U23
Cl1	0.01985 (13)	0.01898 (12)	0.02025 (13)	−0.00230 (9)	−0.00389 (10)	0.00064 (9)
Cl2	0.01669 (12)	0.01806 (12)	0.02796 (15)	0.00393 (9)	0.00359 (10)	0.00006 (10)
Cl3	0.02286 (14)	0.01315 (12)	0.03931 (18)	0.00158 (9)	0.00726 (12)	0.00199 (11)
Cl4	0.02400 (14)	0.02459 (14)	0.02439 (15)	−0.00171 (11)	0.00284 (11)	−0.00901 (11)
N1	0.0155 (4)	0.0167 (4)	0.0163 (4)	0.0010 (3)	0.0017 (3)	0.0000 (3)
N2	0.0176 (4)	0.0160 (4)	0.0169 (4)	−0.0001 (3)	0.0009 (3)	0.0005 (3)
N3	0.0165 (4)	0.0152 (4)	0.0190 (4)	0.0001 (3)	0.0029 (3)	0.0008 (3)
N4	0.0170 (4)	0.0209 (4)	0.0192 (5)	0.0002 (3)	0.0011 (4)	−0.0016 (4)
C1	0.0148 (4)	0.0158 (4)	0.0155 (5)	0.0010 (3)	0.0024 (4)	0.0005 (3)
C2	0.0162 (5)	0.0204 (5)	0.0174 (5)	0.0008 (4)	−0.0001 (4)	−0.0016 (4)
C3	0.0189 (5)	0.0204 (5)	0.0213 (5)	−0.0033 (4)	0.0009 (4)	−0.0026 (4)
C4	0.0230 (6)	0.0158 (5)	0.0227 (6)	−0.0016 (4)	0.0030 (4)	−0.0008 (4)
C5	0.0205 (5)	0.0151 (4)	0.0186 (5)	0.0011 (4)	0.0015 (4)	0.0007 (4)
C6	0.0145 (4)	0.0163 (4)	0.0161 (5)	0.0006 (3)	0.0022 (4)	−0.0002 (3)
C7	0.0149 (4)	0.0167 (4)	0.0161 (5)	0.0007 (3)	0.0005 (4)	0.0007 (4)
C8	0.0145 (4)	0.0149 (4)	0.0157 (5)	0.0013 (3)	0.0021 (4)	0.0007 (3)
C9	0.0158 (5)	0.0145 (4)	0.0190 (5)	0.0017 (3)	0.0018 (4)	0.0005 (4)
C10	0.0171 (5)	0.0139 (4)	0.0210 (5)	0.0012 (3)	0.0027 (4)	0.0008 (4)
C11	0.0158 (5)	0.0137 (4)	0.0183 (5)	0.0005 (3)	0.0028 (4)	0.0016 (3)
C12	0.0183 (5)	0.0164 (5)	0.0174 (5)	−0.0004 (4)	0.0019 (4)	−0.0017 (4)
C13	0.0181 (5)	0.0189 (5)	0.0172 (5)	0.0021 (4)	0.0012 (4)	0.0001 (4)
C14	0.0178 (5)	0.0288 (6)	0.0255 (6)	0.0051 (4)	0.0014 (5)	−0.0020 (5)
C15	0.0243 (6)	0.0317 (7)	0.0286 (7)	0.0078 (5)	0.0054 (5)	−0.0047 (5)
C16	0.0282 (7)	0.0267 (6)	0.0280 (7)	0.0018 (5)	0.0068 (5)	−0.0085 (5)
C17	0.0221 (6)	0.0228 (5)	0.0241 (6)	−0.0016 (4)	0.0024 (5)	−0.0059 (5)
C18	0.0177 (5)	0.0157 (4)	0.0179 (5)	0.0007 (4)	0.0021 (4)	−0.0003 (4)

Cl1—C7	1.7362 (11)	C4—H4	0.908 (18)
Cl2—C9	1.7250 (12)	C5—C6	1.4130 (15)
Cl3—C10	1.7253 (11)	C5—H5	0.927 (18)
Cl4—C12	1.7310 (12)	C7—C8	1.4289 (15)
N1—C8	1.3149 (15)	C8—C9	1.4889 (15)
N1—C1	1.3632 (14)	C9—C10	1.3374 (16)
N2—C7	1.2974 (15)	C10—C11	1.4819 (16)
N2—C6	1.3646 (15)	C11—C12	1.4393 (16)
N3—C11	1.3108 (15)	C13—C14	1.4086 (17)
N3—C18	1.3754 (15)	C13—C18	1.4146 (17)
N4—C12	1.2941 (16)	C14—C15	1.370 (2)
N4—C13	1.3692 (16)	C14—H14	0.974 (18)
C1—C6	1.4156 (15)	C15—C16	1.411 (2)
C1—C2	1.4169 (16)	C15—H15	0.92 (2)
C2—C3	1.3720 (17)	C16—C17	1.3739 (19)
C2—H2	0.934 (18)	C16—H16	0.97 (2)
C3—C4	1.4153 (18)	C17—C18	1.4111 (17)
C3—H3	0.89 (2)	C17—H17	0.994 (18)
C4—C5	1.3669 (17)
C8—N1—C1	117.99 (10)	C10—C9—Cl2	120.67 (9)
C7—N2—C6	116.94 (10)	C8—C9—Cl2	113.54 (8)
C11—N3—C18	117.65 (10)	C9—C10—C11	124.28 (10)
C12—N4—C13	116.81 (10)	C9—C10—Cl3	120.43 (9)
N1—C1—C6	120.87 (10)	C11—C10—Cl3	115.17 (8)
N1—C1—C2	119.99 (10)	N3—C11—C12	120.10 (10)
C6—C1—C2	119.13 (10)	N3—C11—C10	117.49 (10)
C3—C2—C1	119.56 (11)	C12—C11—C10	122.40 (10)
C3—C2—H2	123.7 (11)	N4—C12—C11	123.88 (11)
C1—C2—H2	116.7 (11)	N4—C12—Cl4	115.93 (9)
C2—C3—C4	120.80 (11)	C11—C12—Cl4	120.14 (9)
C2—C3—H3	123.4 (12)	N4—C13—C14	119.24 (11)
C4—C3—H3	115.8 (12)	N4—C13—C18	120.48 (11)
C5—C4—C3	120.93 (11)	C14—C13—C18	120.27 (11)
C5—C4—H4	118.1 (11)	C15—C14—C13	119.33 (12)
C3—C4—H4	121.0 (11)	C15—C14—H14	121.1 (11)
C4—C5—C6	119.17 (11)	C13—C14—H14	119.5 (11)
C4—C5—H5	122.9 (11)	C14—C15—C16	120.76 (13)
C6—C5—H5	117.9 (11)	C14—C15—H15	121.1 (13)
N2—C6—C5	119.15 (10)	C16—C15—H15	118.0 (13)
N2—C6—C1	120.45 (10)	C17—C16—C15	120.76 (13)
C5—C6—C1	120.40 (10)	C17—C16—H16	121.3 (11)
N2—C7—C8	123.65 (10)	C15—C16—H16	117.9 (11)
N2—C7—Cl1	115.75 (8)	C16—C17—C18	119.60 (12)
C8—C7—Cl1	120.58 (8)	C16—C17—H17	120.4 (10)
N1—C8—C7	120.03 (10)	C18—C17—H17	120.0 (10)
N1—C8—C9	116.17 (10)	N3—C18—C17	119.66 (11)
C7—C8—C9	123.69 (10)	N3—C18—C13	121.06 (10)
C10—C9—C8	125.76 (10)	C17—C18—C13	119.27 (11)
C8—N1—C1—C6	−1.53 (16)	C8—C9—C10—Cl3	−176.06 (9)
C8—N1—C1—C2	178.18 (11)	Cl2—C9—C10—Cl3	2.01 (15)
N1—C1—C2—C3	−179.56 (11)	C18—N3—C11—C12	1.06 (16)
C6—C1—C2—C3	0.15 (17)	C18—N3—C11—C10	−178.07 (10)
C1—C2—C3—C4	−0.48 (19)	C9—C10—C11—N3	−54.58 (17)
C2—C3—C4—C5	0.10 (19)	Cl3—C10—C11—N3	121.43 (10)
C3—C4—C5—C6	0.62 (19)	C9—C10—C11—C12	126.31 (13)
C7—N2—C6—C5	−179.23 (11)	Cl3—C10—C11—C12	−57.69 (14)
C7—N2—C6—C1	1.88 (16)	C13—N4—C12—C11	0.56 (17)
C4—C5—C6—N2	−179.84 (11)	C13—N4—C12—Cl4	−176.74 (9)
C4—C5—C6—C1	−0.94 (18)	N3—C11—C12—N4	−1.63 (18)
N1—C1—C6—N2	−0.85 (17)	C10—C11—C12—N4	177.46 (11)
C2—C1—C6—N2	179.44 (11)	N3—C11—C12—Cl4	175.56 (9)
N1—C1—C6—C5	−179.73 (11)	C10—C11—C12—Cl4	−5.35 (16)
C2—C1—C6—C5	0.56 (17)	C12—N4—C13—C14	−179.97 (12)
C6—N2—C7—C8	−0.66 (17)	C12—N4—C13—C18	0.90 (17)
C6—N2—C7—Cl1	−179.12 (9)	N4—C13—C14—C15	−179.18 (13)
C1—N1—C8—C7	2.74 (16)	C18—C13—C14—C15	−0.05 (19)
C1—N1—C8—C9	178.96 (10)	C13—C14—C15—C16	−0.5 (2)
N2—C7—C8—N1	−1.74 (18)	C14—C15—C16—C17	0.7 (2)
Cl1—C7—C8—N1	176.65 (9)	C15—C16—C17—C18	−0.4 (2)
N2—C7—C8—C9	−177.66 (11)	C11—N3—C18—C17	179.47 (11)
Cl1—C7—C8—C9	0.73 (16)	C11—N3—C18—C13	0.36 (16)
N1—C8—C9—C10	124.93 (13)	C16—C17—C18—N3	−179.24 (12)
C7—C8—C9—C10	−59.01 (18)	C16—C17—C18—C13	−0.11 (19)
N1—C8—C9—Cl2	−53.26 (13)	N4—C13—C18—N3	−1.41 (18)
C7—C8—C9—Cl2	122.81 (11)	C14—C13—C18—N3	179.47 (11)
C8—C9—C10—C11	−0.3 (2)	N4—C13—C18—C17	179.47 (11)
Cl2—C9—C10—C11	177.81 (9)	C14—C13—C18—C17	0.35 (18)

Cg1 is the centroid of the C13–C18 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C17—H17···N2i	0.995 (17)	2.454 (17)	3.2609 (16)	137.8 (13)
C16—H16···Cg1ii	0.97 (2)	3.00 (2)	3.9664 (16)	176.0 (16)

Table 1

Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C13–C18 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C17—H17⋯N2i	0.995 (17)	2.454 (17)	3.2609 (16)	137.8 (13)
C16—H16⋯Cg1ii	0.97 (2)	3.00 (2)	3.9664 (16)	176.0 (16)

Symmetry codes: (i) ; (ii) .