11,12-Dichloro-dibenzo[a,c]phenazine.

The title compound, C20H10Cl2N2, has crystallographic twofold rotational symmetry [maximum deviation from the least-squares plane = 0.038 (1) Å]. In the crystal, weak π-π ring stacking inter-actions occur down the a-axis direction [minimum centroid-centroid separation = 3.7163 (8) Å].

Related literature

For the synthesis of the title compound, see: Bellizzi et al. (2006 ▶). For the structures of similar compounds, see: Bellizzi et al. (2006 ▶); Day et al. (2002 ▶); Richards et al. (2009 ▶).

Experimental

Crystal data

C20H10Cl2N2

M = 349.20

Monoclinic,

a = 3.8583 (3) Å

b = 26.2739 (13) Å

c = 15.1147 (10) Å

β = 94.877 (6)°

V = 1526.67 (17) Å3

Z = 4

Mo Kα radiation

μ = 0.43 mm−1

T = 293 K

0.32 × 0.14 × 0.09 mm

Data collection

Oxford Diffraction Xcalibur Sapphire3 CCD diffractometer

Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009 ▶) T min = 0.915, T max = 1.000

5082 measured reflections

2520 independent reflections

1372 reflections with I > 2σ(I)

R int = 0.020

Refinement

R[F 2 > 2σ(F 2)] = 0.039

wR(F 2) = 0.104

S = 0.83

2520 reflections

109 parameters

H-atom parameters constrained

Δρmax = 0.26 e Å−3

Δρmin = −0.25 e Å−3

Data collection: CrysAlis CCD (Oxford Diffraction, 2009 ▶); cell refinement: CrysAlis RED (Oxford Diffraction, 2009 ▶); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: PLATON (Spek, 2009 ▶); software used to prepare material for publication: SHELXTL (Sheldrick, 2008 ▶).

Click here for additional data file.

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536812049690/zs2242sup1.cif

Click here for additional data file.

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812049690/zs2242Isup2.hkl

Click here for additional data file.

Supplementary material file. DOI: 10.1107/S1600536812049690/zs2242Isup3.cml

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

C20H10Cl2N2	F(000) = 712
Mr = 349.20	Dx = 1.519 Mg m−3
Monoclinic, C2/c	Melting point: 546 K
Hall symbol: -C 2yc	Mo Kα radiation, λ = 0.71073 Å
a = 3.8583 (3) Å	Cell parameters from 1714 reflections
b = 26.2739 (13) Å	θ = 4.1–32.5°
c = 15.1147 (10) Å	µ = 0.43 mm−1
β = 94.877 (6)°	T = 293 K
V = 1526.67 (17) Å3	Needle, yellow
Z = 4	0.32 × 0.14 × 0.09 mm

Oxford Diffraction Xcalibur Sapphire3 CCD diffractometer	2520 independent reflections
Radiation source: Enhance (Mo) X-ray Source	1372 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.020
Detector resolution: 16.1790 pixels mm-1	θmax = 32.6°, θmin = 4.1°
ω scans	h = −5→5
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	k = −27→38
Tmin = 0.915, Tmax = 1.000	l = −21→10
5082 measured reflections

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)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.104	H-atom parameters constrained
S = 0.83	w = 1/[σ2(Fo2) + (0.0575P)2] where P = (Fo2 + 2Fc2)/3
2520 reflections	(Δ/σ)max = 0.001
109 parameters	Δρmax = 0.26 e Å−3
0 restraints	Δρmin = −0.25 e Å−3

Experimental. Hydrogen atoms were included in calculated positions with a C—H distance of 0.93 Å and were included in the refinement in riding motion approximation with Uiso = 1.2Ueq of the carrier atom.

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.

	x	y	z	Uiso*/Ueq
Cl1	0.13563 (12)	1.243825 (14)	0.15408 (3)	0.07256 (18)
C1	0.0618 (3)	1.18700 (5)	0.20681 (10)	0.0463 (3)
C2	0.1244 (3)	1.14234 (5)	0.16590 (9)	0.0430 (3)
H2	0.2072	1.1427	0.1099	0.052*
C3	0.0651 (3)	1.09527 (4)	0.20751 (8)	0.0355 (3)
N1	0.1324 (3)	1.05122 (4)	0.16541 (7)	0.0356 (2)
C4	0.0669 (3)	1.00812 (4)	0.20704 (8)	0.0308 (3)
C5	0.1338 (3)	0.95984 (4)	0.16356 (8)	0.0306 (3)
C6	0.2605 (3)	0.95979 (5)	0.07952 (8)	0.0390 (3)
H6	0.3017	0.9906	0.0519	0.047*
C7	0.3246 (4)	0.91492 (5)	0.03731 (9)	0.0447 (3)
H7	0.4078	0.9152	−0.0187	0.054*
C8	0.2642 (4)	0.86907 (5)	0.07896 (9)	0.0472 (4)
H8	0.3089	0.8386	0.0508	0.057*
C9	0.1394 (3)	0.86825 (5)	0.16127 (9)	0.0421 (3)
H9	0.1010	0.8371	0.1880	0.051*
C10	0.0685 (3)	0.91342 (4)	0.20592 (8)	0.0321 (3)

	U11	U22	U33	U12	U13	U23
Cl1	0.0829 (3)	0.0336 (2)	0.1023 (4)	−0.00414 (17)	0.0140 (3)	0.0163 (2)
C1	0.0413 (8)	0.0305 (6)	0.0665 (9)	−0.0025 (5)	0.0004 (7)	0.0067 (6)
C2	0.0440 (8)	0.0364 (7)	0.0490 (8)	−0.0003 (6)	0.0053 (6)	0.0062 (6)
C3	0.0333 (7)	0.0311 (6)	0.0417 (6)	−0.0006 (5)	0.0010 (5)	0.0014 (5)
N1	0.0380 (6)	0.0323 (5)	0.0366 (5)	0.0000 (4)	0.0047 (5)	0.0029 (4)
C4	0.0281 (7)	0.0325 (6)	0.0315 (6)	0.0005 (4)	0.0014 (5)	0.0018 (5)
C5	0.0272 (6)	0.0327 (6)	0.0315 (6)	0.0025 (5)	0.0006 (5)	−0.0012 (5)
C6	0.0393 (7)	0.0410 (7)	0.0375 (7)	0.0028 (5)	0.0074 (6)	0.0012 (5)
C7	0.0450 (8)	0.0526 (8)	0.0373 (7)	0.0081 (6)	0.0072 (6)	−0.0067 (6)
C8	0.0549 (9)	0.0403 (7)	0.0464 (8)	0.0090 (6)	0.0041 (6)	−0.0115 (6)
C9	0.0476 (8)	0.0317 (6)	0.0467 (8)	0.0028 (5)	0.0018 (6)	−0.0027 (5)
C10	0.0290 (6)	0.0316 (6)	0.0351 (6)	0.0014 (4)	−0.0012 (5)	−0.0011 (5)

Cl1—C1	1.7274 (13)	C5—C10	1.4101 (15)
C1—C2	1.3576 (17)	C6—C7	1.3731 (17)
C1—C1i	1.428 (3)	C6—H6	0.9300
C2—C3	1.4147 (16)	C7—C8	1.3879 (18)
C2—H2	0.9300	C7—H7	0.9300
C3—N1	1.3564 (14)	C8—C9	1.3719 (18)
C3—C3i	1.418 (2)	C8—H8	0.9300
N1—C4	1.3301 (14)	C9—C10	1.4037 (15)
C4—C4i	1.438 (2)	C9—H9	0.9300
C4—C5	1.4616 (15)	C10—C10i	1.475 (2)
C5—C6	1.3991 (16)
C2—C1—C1i	120.17 (8)	C7—C6—C5	120.89 (12)
C2—C1—Cl1	119.62 (11)	C7—C6—H6	119.6
C1i—C1—Cl1	120.20 (5)	C5—C6—H6	119.6
C1—C2—C3	120.76 (12)	C6—C7—C8	119.38 (12)
C1—C2—H2	119.6	C6—C7—H7	120.3
C3—C2—H2	119.6	C8—C7—H7	120.3
N1—C3—C2	119.52 (11)	C9—C8—C7	120.69 (12)
N1—C3—C3i	121.43 (6)	C9—C8—H8	119.7
C2—C3—C3i	119.05 (7)	C7—C8—H8	119.7
C4—N1—C3	116.93 (10)	C8—C9—C10	121.36 (12)
N1—C4—C4i	121.64 (6)	C8—C9—H9	119.3
N1—C4—C5	118.57 (10)	C10—C9—H9	119.3
C4i—C4—C5	119.79 (6)	C9—C10—C5	117.61 (11)
C6—C5—C10	120.06 (11)	C9—C10—C10i	122.27 (7)
C6—C5—C4	119.85 (10)	C5—C10—C10i	120.12 (6)
C10—C5—C4	120.08 (10)
C3—N1—C4—C4i	−0.40 (17)	N1—C4—C4i—N1i	0.24 (19)
C4—N1—C3—C2	−179.01 (11)	N1—C4—C4i—C5i	−179.76 (11)
C4—N1—C3—C3i	0.75 (17)	C5—C4—C4i—N1i	−179.76 (11)
C3—N1—C4—C5	179.59 (11)	C5—C4—C4i—C5i	0.25 (17)
Cl1—C1—C1i—C2i	179.08 (10)	C4—C5—C6—C7	−179.86 (12)
C2—C1—C1i—C2i	−1.40 (19)	C10—C5—C6—C7	−0.32 (18)
Cl1—C1—C1i—Cl1i	−0.44 (15)	C4—C5—C10—C9	−179.65 (11)
C2—C1—C1i—Cl1i	179.08 (10)	C4—C5—C10—C10i	0.19 (17)
C1i—C1—C2—C3	0.67 (18)	C6—C5—C10—C9	0.80 (17)
Cl1—C1—C2—C3	−179.81 (10)	C6—C5—C10—C10i	−179.36 (11)
C1—C2—C3—C3i	0.74 (18)	C5—C6—C7—C8	−0.3 (2)
C1—C2—C3—N1	−179.50 (12)	C6—C7—C8—C9	0.4 (2)
N1—C3—C3i—N1i	−0.96 (18)	C7—C8—C9—C10	0.1 (2)
C2—C3—C3i—C2i	−1.44 (17)	C8—C9—C10—C5	−0.69 (18)
N1—C3—C3i—C2i	178.80 (11)	C8—C9—C10—C10i	179.48 (12)
C2—C3—C3i—N1i	178.80 (11)	C5—C10—C10i—C5i	−0.17 (17)
N1—C4—C5—C6	−0.68 (17)	C5—C10—C10i—C9i	179.66 (11)
N1—C4—C5—C10	179.77 (11)	C9—C10—C10i—C5i	179.66 (11)
C4i—C4—C5—C6	179.32 (11)	C9—C10—C10i—C9i	−0.51 (18)
C4i—C4—C5—C10	−0.24 (17)