The crystal packing of 4,7-dichloro- and 4,7-dibromobenzo[c]furazan 1-oxide

The molecular structures of 4,7-di­chloro­benzo­[c]­fur­azan 1-­oxide, C₆H₂Cl₂N₂O₂, (I), and 4,7-di­bromo­benzo­[c]­fur­azan 1-oxide, C₆H₂Br₂N₂O₂, (II), are normal. Compound (I) occurs in two polymorphic forms. One polymorph contains one mol­ecule in the asymmetric unit, organized into two-dimensional sheets involving intermolecular N...Cl and O...Cl inter­actions. The second polymorph has three mol­ecules in the asymmetric unit, organized into two crystallographically different two-dimensional sheets with similar interactions. Compound (II) is isomorphous with the second polymorph of (I). The three two-dimensional sheets in the two polymorphs comprise a set of three two-dimensional polymorphic arrangements.

Computing details

For all compounds, data collection: SMART (Siemens, 1995); cell refinement: SAINT (Siemens, 1995); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 1995); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

(DCL-I) 4,7-dichlorobenzo[c]furazan 1-oxide, polymorph I

Crystal data

C6H2Cl2N2O2	Z = 2
Mr = 205.00	F(000) = 204
Triclinic, P1	Dx = 1.812 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.357 (2) Å	Cell parameters from 2332 reflections
b = 7.667 (2) Å	θ = 2.7–27.5°
c = 8.190 (2) Å	µ = 0.82 mm^−1
α = 92.10 (1)°	T = 173 K
β = 109.81 (1)°	Prism, yellow
γ = 117.31 (1)°	0.3 × 0.3 × 0.1 mm
V = 375.8 (2) Å^3

Data collection

Siemens SMART CCD area-detector diffractometer	1695 independent reflections
Radiation source: fine-focus sealed tube	1447 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.021
ω scans	θmax = 27.5°, θmin = 2.7°
Absorption correction: multi-scan [SADABS; Sheldrick (1996) and Blessing (1995)]	h = −9→9
Tmin = 0.78, Tmax = 0.92	k = −9→9
4117 measured reflections	l = −10→10

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.095	All H-atom parameters refined
S = 1.09	w = 1/[σ^2(Fo^2) + (0.0591P)^2 + 0.0163P] where P = (Fo^2 + 2Fc^2)/3
1695 reflections	(Δ/σ)max = 0.001
117 parameters	Δρmax = 0.40 e Å^−3
0 restraints	Δρmin = −0.34 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Cl3	0.78094 (7)	0.99930 (7)	1.20464 (5)	0.03031 (16)
Cl6	0.35870 (8)	0.62810 (8)	0.37792 (5)	0.03238 (17)
O1	0.0421 (2)	0.31621 (19)	0.54816 (17)	0.0342 (3)
O2	0.1670 (2)	0.42708 (19)	0.85108 (16)	0.0291 (3)
N1	0.1871 (2)	0.4513 (2)	0.68087 (18)	0.0239 (3)
N2	0.3423 (2)	0.5925 (2)	0.98315 (18)	0.0254 (3)
C1	0.3702 (3)	0.6289 (2)	0.7162 (2)	0.0194 (3)
C2	0.4622 (3)	0.7114 (2)	0.9024 (2)	0.0193 (3)
C3	0.6620 (3)	0.9018 (3)	0.9777 (2)	0.0215 (3)
C4	0.7545 (3)	1.0000 (3)	0.8672 (3)	0.0266 (4)
H4	0.881 (3)	1.132 (3)	0.910 (3)	0.028 (5)*
C5	0.6581 (3)	0.9150 (3)	0.6790 (2)	0.0265 (4)
H5	0.727 (4)	0.983 (3)	0.610 (3)	0.037 (6)*
C6	0.4705 (3)	0.7324 (3)	0.6025 (2)	0.0226 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl3	0.0272 (3)	0.0321 (3)	0.0221 (2)	0.0123 (2)	0.00398 (18)	−0.00301 (18)
Cl6	0.0452 (3)	0.0417 (3)	0.0188 (2)	0.0263 (2)	0.0156 (2)	0.0094 (2)
O1	0.0330 (7)	0.0239 (7)	0.0235 (6)	0.0031 (6)	0.0038 (5)	−0.0036 (5)
O2	0.0281 (7)	0.0229 (6)	0.0246 (6)	0.0021 (5)	0.0129 (5)	0.0068 (5)
N1	0.0252 (7)	0.0201 (7)	0.0197 (7)	0.0068 (6)	0.0081 (6)	0.0038 (6)
N2	0.0254 (7)	0.0250 (8)	0.0197 (7)	0.0067 (6)	0.0106 (6)	0.0050 (6)
C1	0.0205 (8)	0.0183 (8)	0.0182 (7)	0.0087 (7)	0.0081 (6)	0.0042 (6)
C2	0.0202 (8)	0.0202 (8)	0.0194 (8)	0.0104 (7)	0.0094 (6)	0.0054 (6)
C3	0.0188 (8)	0.0204 (8)	0.0213 (8)	0.0085 (7)	0.0060 (6)	0.0026 (6)
C4	0.0209 (8)	0.0214 (9)	0.0323 (9)	0.0065 (7)	0.0106 (7)	0.0078 (7)
C5	0.0267 (9)	0.0298 (10)	0.0304 (9)	0.0141 (8)	0.0186 (8)	0.0161 (8)
C6	0.0277 (9)	0.0272 (9)	0.0206 (8)	0.0163 (7)	0.0139 (7)	0.0101 (7)

Geometric parameters (Å, º)

Cl3—C3	1.7250 (17)	C1—C6	1.422 (2)
Cl6—C6	1.7214 (17)	C2—C3	1.422 (2)
O1—N1	1.2287 (19)	C3—C4	1.359 (2)
O2—N2	1.3764 (19)	C4—C5	1.437 (3)
O2—N1	1.4604 (18)	C4—H4	0.95 (2)
N1—C1	1.333 (2)	C5—C6	1.354 (3)
N2—C2	1.322 (2)	C5—H5	0.91 (2)
C1—C2	1.421 (2)
N2—O2—N1	109.32 (12)	C4—C3—Cl3	122.13 (14)
O1—N1—C1	136.55 (15)	C2—C3—Cl3	119.50 (12)
O1—N1—O2	117.61 (14)	C3—C4—C5	121.80 (17)
C1—N1—O2	105.83 (12)	C3—C4—H4	121.2 (12)
C2—N2—O2	105.49 (13)	C5—C4—H4	116.9 (12)
N1—C1—C2	107.03 (14)	C6—C5—C4	121.71 (16)
N1—C1—C6	131.03 (15)	C6—C5—H5	118.9 (14)
C2—C1—C6	121.94 (15)	C4—C5—H5	119.3 (14)
N2—C2—C1	112.33 (15)	C5—C6—C1	117.13 (15)
N2—C2—C3	128.64 (15)	C5—C6—Cl6	121.67 (13)
C1—C2—C3	119.03 (14)	C1—C6—Cl6	121.20 (14)
C4—C3—C2	118.37 (15)
N2—O2—N1—O1	−179.67 (15)	N2—C2—C3—C4	−178.56 (18)
N2—O2—N1—C1	−0.56 (17)	C1—C2—C3—C4	1.6 (2)
N1—O2—N2—C2	0.27 (17)	N2—C2—C3—Cl3	2.2 (2)
O1—N1—C1—C2	179.4 (2)	C1—C2—C3—Cl3	−177.65 (11)
O2—N1—C1—C2	0.58 (17)	C2—C3—C4—C5	−1.1 (3)
O1—N1—C1—C6	−0.3 (4)	Cl3—C3—C4—C5	178.10 (13)
O2—N1—C1—C6	−179.11 (17)	C3—C4—C5—C6	−0.2 (3)
O2—N2—C2—C1	0.10 (18)	C4—C5—C6—C1	0.9 (3)
O2—N2—C2—C3	−179.77 (16)	C4—C5—C6—Cl6	−178.49 (13)
N1—C1—C2—N2	−0.46 (19)	N1—C1—C6—C5	179.25 (17)
C6—C1—C2—N2	179.27 (16)	C2—C1—C6—C5	−0.4 (3)
N1—C1—C2—C3	179.42 (15)	N1—C1—C6—Cl6	−1.3 (3)
C6—C1—C2—C3	−0.8 (2)	C2—C1—C6—Cl6	179.01 (12)

(DCL-II) 4,7-dichlorobenzo[c]furazan 1-oxide, polymorph II

Crystal data

C6H2Cl2N2O2	F(000) = 2448
Mr = 205.00	Dx = 1.804 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 1162 reflections
a = 21.828 (5) Å	θ = 2.0–27.4°
b = 7.819 (2) Å	µ = 0.81 mm^−1
c = 27.501 (7) Å	T = 173 K
β = 105.21 (3)°	Prism, yellow
V = 4529 (2) Å^3	0.45 × 0.20 × 0.20 mm
Z = 24

Data collection

Siemens SMART CCD area-detector diffractometer	5149 independent reflections
Radiation source: fine-focus sealed tube	4301 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.020
ω scans	θmax = 27.5°, θmin = 1.5°
Absorption correction: multi-scan [SADABS; Sheldrick (1996) and Blessing (1995)]	h = −28→24
Tmin = 0.72, Tmax = 0.85	k = −10→8
13985 measured reflections	l = −33→35

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.081	H-atom parameters constrained
S = 1.06	w = 1/[σ^2(Fo^2) + (0.035P)^2 + 4.8P] where P = (Fo^2 + 2Fc^2)/3
5149 reflections	(Δ/σ)max = 0.002
325 parameters	Δρmax = 0.42 e Å^−3
0 restraints	Δρmin = −0.29 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
N1A	0.61139 (7)	0.51732 (19)	0.60152 (6)	0.0260 (3)
O1A	0.58337 (7)	0.62123 (17)	0.56988 (5)	0.0348 (3)
O2A	0.65613 (6)	0.58340 (16)	0.64651 (5)	0.0315 (3)
N2A	0.68149 (8)	0.4496 (2)	0.67789 (6)	0.0294 (3)
C1A	0.61222 (8)	0.3477 (2)	0.60691 (6)	0.0225 (4)
C2A	0.65534 (8)	0.3104 (2)	0.65400 (6)	0.0231 (4)
C3A	0.66634 (8)	0.1359 (2)	0.66930 (7)	0.0259 (4)
C4A	0.63529 (9)	0.0132 (2)	0.63739 (7)	0.0299 (4)
H4A	0.6424	−0.1010	0.6466	0.036*
C5A	0.59196 (9)	0.0534 (2)	0.58991 (7)	0.0290 (4)
H5A	0.5717	−0.0353	0.5694	0.035*
C6A	0.57953 (8)	0.2171 (2)	0.57395 (7)	0.0246 (4)
Cl3A	0.71888 (2)	0.08942 (7)	0.726290 (17)	0.03335 (12)
Cl6A	0.52698 (2)	0.26927 (6)	0.517471 (16)	0.03120 (12)
N1B	0.38241 (7)	0.6371 (2)	0.22086 (5)	0.0253 (3)
O1B	0.41019 (7)	0.74086 (17)	0.25229 (5)	0.0330 (3)
O2B	0.33918 (6)	0.70318 (17)	0.17476 (5)	0.0316 (3)
N2B	0.31265 (7)	0.5682 (2)	0.14430 (6)	0.0294 (4)
C1B	0.37978 (8)	0.4670 (2)	0.21649 (6)	0.0222 (4)
C2B	0.33703 (8)	0.4294 (2)	0.16923 (7)	0.0236 (4)
C3B	0.32499 (9)	0.2550 (2)	0.15467 (7)	0.0269 (4)
C4B	0.35485 (9)	0.1330 (2)	0.18709 (8)	0.0317 (4)
H4B	0.3471	0.0188	0.1782	0.038*
C5B	0.39811 (9)	0.1732 (2)	0.23476 (7)	0.0317 (4)
H5B	0.4175	0.0846	0.2558	0.038*
C6B	0.41132 (8)	0.3367 (2)	0.24985 (7)	0.0252 (4)
Cl3B	0.27372 (2)	0.20943 (7)	0.096950 (18)	0.03570 (13)
Cl6B	0.46495 (2)	0.39035 (7)	0.305879 (17)	0.03264 (12)
N1C	0.14069 (8)	−0.0164 (2)	−0.02400 (6)	0.0290 (3)
O1C	0.17316 (7)	0.06822 (19)	0.01082 (5)	0.0400 (4)
O2C	0.10012 (7)	0.07642 (17)	−0.06643 (5)	0.0329 (3)
N2C	0.06714 (8)	−0.0381 (2)	−0.10139 (6)	0.0296 (3)
C1C	0.13052 (8)	−0.1818 (2)	−0.03501 (6)	0.0233 (4)
C2C	0.08570 (8)	−0.1913 (2)	−0.08255 (6)	0.0236 (4)
C3C	0.06615 (8)	−0.3546 (2)	−0.10421 (7)	0.0251 (4)
C4C	0.09008 (9)	−0.4954 (2)	−0.07769 (7)	0.0299 (4)
H4C	0.0770	−0.6026	−0.0911	0.036*
C5C	0.13526 (9)	−0.4846 (3)	−0.02923 (7)	0.0302 (4)
H5C	0.1505	−0.5849	−0.0121	0.036*
C6C	0.15622 (8)	−0.3322 (3)	−0.00787 (7)	0.0262 (4)
Cl3C	0.01400 (2)	−0.35943 (7)	−0.163298 (17)	0.03510 (12)
Cl6C	0.21209 (2)	−0.31949 (7)	0.049213 (17)	0.03537 (13)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1A	0.0283 (8)	0.0226 (8)	0.0255 (8)	0.0003 (6)	0.0041 (6)	0.0003 (6)
O1A	0.0397 (8)	0.0250 (7)	0.0351 (7)	0.0051 (6)	0.0014 (6)	0.0087 (6)
O2A	0.0380 (8)	0.0218 (7)	0.0303 (7)	−0.0031 (6)	0.0013 (6)	−0.0025 (5)
N2A	0.0321 (8)	0.0271 (8)	0.0260 (8)	−0.0005 (7)	0.0022 (7)	0.0008 (6)
C1A	0.0234 (8)	0.0219 (9)	0.0230 (8)	0.0019 (7)	0.0077 (7)	0.0006 (7)
C2A	0.0230 (8)	0.0255 (9)	0.0210 (8)	0.0015 (7)	0.0059 (7)	−0.0006 (7)
C3A	0.0248 (9)	0.0286 (10)	0.0243 (9)	0.0056 (7)	0.0066 (7)	0.0050 (7)
C4A	0.0361 (10)	0.0206 (9)	0.0347 (10)	0.0045 (8)	0.0122 (8)	0.0029 (8)
C5A	0.0346 (10)	0.0230 (10)	0.0297 (9)	−0.0034 (8)	0.0091 (8)	−0.0051 (7)
C6A	0.0238 (9)	0.0282 (10)	0.0216 (8)	−0.0001 (7)	0.0056 (7)	−0.0021 (7)
Cl3A	0.0299 (2)	0.0420 (3)	0.0267 (2)	0.0081 (2)	0.00500 (18)	0.01088 (19)
Cl6A	0.0284 (2)	0.0386 (3)	0.0231 (2)	−0.00095 (19)	0.00046 (18)	−0.00030 (18)
N1B	0.0269 (8)	0.0241 (8)	0.0230 (7)	−0.0007 (6)	0.0032 (6)	−0.0012 (6)
O1B	0.0383 (8)	0.0268 (7)	0.0301 (7)	−0.0048 (6)	0.0021 (6)	−0.0080 (6)
O2B	0.0379 (8)	0.0226 (7)	0.0291 (7)	0.0011 (6)	−0.0001 (6)	0.0018 (5)
N2B	0.0298 (8)	0.0291 (9)	0.0266 (8)	−0.0002 (7)	0.0023 (7)	−0.0017 (6)
C1B	0.0219 (8)	0.0213 (9)	0.0241 (8)	−0.0019 (7)	0.0073 (7)	−0.0019 (7)
C2B	0.0227 (9)	0.0255 (10)	0.0233 (9)	−0.0003 (7)	0.0071 (7)	−0.0012 (7)
C3B	0.0260 (9)	0.0286 (10)	0.0267 (9)	−0.0039 (7)	0.0081 (7)	−0.0048 (7)
C4B	0.0379 (11)	0.0208 (10)	0.0379 (11)	−0.0039 (8)	0.0126 (9)	−0.0041 (8)
C5B	0.0374 (10)	0.0244 (10)	0.0327 (10)	0.0041 (8)	0.0080 (8)	0.0054 (8)
C6B	0.0240 (9)	0.0278 (10)	0.0231 (8)	0.0010 (7)	0.0054 (7)	0.0011 (7)
Cl3B	0.0314 (2)	0.0434 (3)	0.0306 (2)	−0.0075 (2)	0.00511 (19)	−0.0131 (2)
Cl6B	0.0297 (2)	0.0406 (3)	0.0241 (2)	0.00456 (19)	0.00077 (18)	0.00018 (19)
N1C	0.0307 (8)	0.0299 (9)	0.0244 (8)	−0.0022 (7)	0.0038 (6)	0.0005 (6)
O1C	0.0444 (9)	0.0380 (8)	0.0323 (8)	−0.0121 (7)	0.0007 (6)	−0.0088 (6)
O2C	0.0411 (8)	0.0241 (7)	0.0301 (7)	0.0015 (6)	0.0036 (6)	0.0017 (5)
N2C	0.0329 (8)	0.0277 (8)	0.0256 (8)	0.0014 (7)	0.0031 (6)	0.0012 (6)
C1C	0.0228 (8)	0.0246 (9)	0.0229 (8)	−0.0017 (7)	0.0067 (7)	−0.0001 (7)
C2C	0.0214 (8)	0.0276 (10)	0.0222 (8)	0.0012 (7)	0.0065 (7)	0.0038 (7)
C3C	0.0233 (8)	0.0294 (10)	0.0220 (8)	−0.0017 (7)	0.0049 (7)	−0.0008 (7)
C4C	0.0345 (10)	0.0238 (10)	0.0318 (10)	−0.0008 (8)	0.0095 (8)	−0.0015 (7)
C5C	0.0320 (10)	0.0296 (10)	0.0293 (10)	0.0066 (8)	0.0085 (8)	0.0069 (8)
C6C	0.0218 (8)	0.0351 (10)	0.0211 (8)	0.0033 (7)	0.0045 (7)	0.0048 (7)
Cl3C	0.0326 (2)	0.0436 (3)	0.0245 (2)	−0.0050 (2)	−0.00063 (18)	−0.00347 (19)
Cl6C	0.0264 (2)	0.0520 (3)	0.0238 (2)	0.0020 (2)	−0.00040 (18)	0.0071 (2)

Geometric parameters (Å, º)

N1A—O1A	1.2295 (19)	C3B—C4B	1.351 (3)
N1A—C1A	1.334 (2)	C3B—Cl3B	1.7225 (19)
N1A—O2A	1.455 (2)	C4B—C5B	1.435 (3)
O2A—N2A	1.377 (2)	C4B—H4B	0.9300
N2A—C2A	1.321 (2)	C5B—C6B	1.351 (3)
C1A—C2A	1.417 (2)	C5B—H5B	0.9300
C1A—C6A	1.426 (2)	C6B—Cl6B	1.7246 (19)
C2A—C3A	1.430 (3)	N1C—O1C	1.225 (2)
C3A—C4A	1.356 (3)	N1C—C1C	1.333 (2)
C3A—Cl3A	1.7207 (19)	N1C—O2C	1.460 (2)
C4A—C5A	1.432 (3)	O2C—N2C	1.371 (2)
C4A—H4A	0.9300	N2C—C2C	1.326 (2)
C5A—C6A	1.357 (3)	C1C—C2C	1.415 (2)
C5A—H5A	0.9300	C1C—C6C	1.426 (3)
C6A—Cl6A	1.7203 (19)	C2C—C3C	1.426 (3)
N1B—O1B	1.2239 (19)	C3C—C4C	1.348 (3)
N1B—C1B	1.335 (2)	C3C—Cl3C	1.7225 (19)
N1B—O2B	1.4618 (19)	C4C—C5C	1.437 (3)
O2B—N2B	1.377 (2)	C4C—H4C	0.9300
N2B—C2B	1.319 (2)	C5C—C6C	1.354 (3)
C1B—C2B	1.418 (2)	C5C—H5C	0.9300
C1B—C6B	1.422 (2)	C6C—Cl6C	1.7196 (19)
C2B—C3B	1.426 (3)
O1A—N1A—C1A	136.49 (16)	C4B—C3B—Cl3B	123.14 (15)
O1A—N1A—O2A	117.73 (14)	C2B—C3B—Cl3B	118.93 (14)
C1A—N1A—O2A	105.78 (13)	C3B—C4B—C5B	122.43 (17)
N2A—O2A—N1A	109.45 (12)	C3B—C4B—H4B	118.8
C2A—N2A—O2A	105.31 (14)	C5B—C4B—H4B	118.8
N1A—C1A—C2A	106.99 (15)	C6B—C5B—C4B	121.60 (18)
N1A—C1A—C6A	130.62 (17)	C6B—C5B—H5B	119.2
C2A—C1A—C6A	122.37 (16)	C4B—C5B—H5B	119.2
N2A—C2A—C1A	112.46 (16)	C5B—C6B—C1B	116.83 (17)
N2A—C2A—C3A	128.51 (16)	C5B—C6B—Cl6B	123.01 (15)
C1A—C2A—C3A	119.02 (16)	C1B—C6B—Cl6B	120.14 (14)
C4A—C3A—C2A	117.92 (16)	O1C—N1C—C1C	136.81 (17)
C4A—C3A—Cl3A	122.73 (15)	O1C—N1C—O2C	117.47 (15)
C2A—C3A—Cl3A	119.34 (14)	C1C—N1C—O2C	105.72 (14)
C3A—C4A—C5A	122.21 (17)	N2C—O2C—N1C	109.43 (13)
C3A—C4A—H4A	118.9	C2C—N2C—O2C	105.40 (14)
C5A—C4A—H4A	118.9	N1C—C1C—C2C	107.13 (16)
C6A—C5A—C4A	122.04 (17)	N1C—C1C—C6C	131.42 (16)
C6A—C5A—H5A	119.0	C2C—C1C—C6C	121.45 (16)
C4A—C5A—H5A	119.0	N2C—C2C—C1C	112.32 (16)
C5A—C6A—C1A	116.44 (16)	N2C—C2C—C3C	128.21 (16)
C5A—C6A—Cl6A	123.02 (14)	C1C—C2C—C3C	119.47 (16)
C1A—C6A—Cl6A	120.54 (14)	C4C—C3C—C2C	118.30 (16)
O1B—N1B—C1B	136.50 (16)	C4C—C3C—Cl3C	123.99 (15)
O1B—N1B—O2B	117.77 (14)	C2C—C3C—Cl3C	117.71 (14)
C1B—N1B—O2B	105.73 (13)	C3C—C4C—C5C	121.87 (18)
N2B—O2B—N1B	109.24 (13)	C3C—C4C—H4C	119.1
C2B—N2B—O2B	105.45 (14)	C5C—C4C—H4C	119.1
N1B—C1B—C2B	106.94 (15)	C6C—C5C—C4C	121.70 (17)
N1B—C1B—C6B	130.81 (16)	C6C—C5C—H5C	119.2
C2B—C1B—C6B	122.25 (16)	C4C—C5C—H5C	119.2
N2B—C2B—C1B	112.63 (16)	C5C—C6C—C1C	117.18 (16)
N2B—C2B—C3B	128.41 (17)	C5C—C6C—Cl6C	121.67 (15)
C1B—C2B—C3B	118.95 (16)	C1C—C6C—Cl6C	121.15 (15)
C4B—C3B—C2B	117.93 (17)

(DBR-II) 4,7-dibromobenzo[c]furazan 1-oxide

Crystal data

C6H2Br2N2O2	F(000) = 3312
Mr = 293.92	Dx = 2.439 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 2707 reflections
a = 22.810 (6) Å	θ = 2.7–27.2°
b = 7.835 (2) Å	µ = 10.08 mm^−1
c = 27.859 (7) Å	T = 175 K
β = 105.31 (2)°	Prism, yellow
V = 4802 (2) Å^3	0.25 × 0.20 × 0.15 mm
Z = 24

Data collection

Siemens SMART CCD area-detector diffractometer	5513 independent reflections
Radiation source: fine-focus sealed tube	4095 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.052
ω scans	θmax = 27.5°, θmin = 1.5°
Absorption correction: multi-scan [SADABS; Sheldrick (1996) and Blessing (1995)]	h = −29→29
Tmin = 0.10, Tmax = 0.22	k = −10→10
27206 measured reflections	l = −36→36

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.058	H-atom parameters constrained
S = 1.05	w = 1/[σ^2(Fo^2) + (0.018P)^2 + 6.94P] where P = (Fo^2 + 2Fc^2)/3
5513 reflections	(Δ/σ)max = 0.002
325 parameters	Δρmax = 0.92 e Å^−3
0 restraints	Δρmin = −0.66 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
N1A	0.61289 (13)	0.5134 (4)	0.60207 (11)	0.0217 (7)
O1A	0.58574 (12)	0.6179 (3)	0.57129 (9)	0.0293 (6)
O2A	0.65653 (11)	0.5787 (3)	0.64577 (9)	0.0264 (6)
N2A	0.68127 (14)	0.4436 (4)	0.67665 (11)	0.0250 (7)
C1A	0.61297 (15)	0.3434 (4)	0.60731 (12)	0.0167 (7)
C2A	0.65539 (16)	0.3058 (4)	0.65353 (12)	0.0194 (8)
C3A	0.66535 (16)	0.1311 (5)	0.66841 (12)	0.0200 (8)
C4A	0.63449 (16)	0.0103 (5)	0.63756 (13)	0.0248 (8)
H4AA	0.6413	−0.1061	0.6468	0.030*
C5A	0.59174 (17)	0.0510 (5)	0.59114 (13)	0.0255 (9)
H5AA	0.5709	−0.0392	0.5709	0.031*
C6A	0.58025 (15)	0.2136 (5)	0.57533 (12)	0.0194 (8)
Br3A	0.722237 (17)	0.07841 (5)	0.729094 (13)	0.02587 (9)
Br6A	0.523647 (16)	0.27066 (5)	0.515143 (13)	0.02463 (9)
N1B	0.38075 (13)	0.6318 (4)	0.22059 (10)	0.0208 (7)
O1B	0.40637 (11)	0.7367 (3)	0.25162 (9)	0.0269 (6)
O2B	0.33936 (11)	0.6971 (3)	0.17470 (9)	0.0269 (6)
N2B	0.31437 (13)	0.5620 (4)	0.14458 (11)	0.0226 (7)
C1B	0.37905 (15)	0.4614 (4)	0.21596 (12)	0.0175 (8)
C2B	0.33837 (15)	0.4240 (4)	0.16908 (12)	0.0174 (8)
C3B	0.32676 (16)	0.2503 (5)	0.15495 (13)	0.0222 (8)
C4B	0.35586 (17)	0.1289 (5)	0.18693 (14)	0.0270 (9)
H4BA	0.3485	0.0122	0.1781	0.032*
C5B	0.39738 (17)	0.1706 (5)	0.23364 (13)	0.0248 (8)
H5BA	0.4169	0.0805	0.2547	0.030*
C6B	0.40984 (15)	0.3328 (5)	0.24886 (12)	0.0189 (8)
Br3B	0.271913 (17)	0.19770 (5)	0.093357 (13)	0.02823 (10)
Br6B	0.466884 (17)	0.38959 (5)	0.308932 (13)	0.02531 (10)
N1C	0.14026 (13)	−0.0136 (4)	−0.02499 (10)	0.0224 (7)
O1C	0.17100 (12)	0.0710 (3)	0.00960 (9)	0.0352 (7)
O2C	0.10200 (11)	0.0790 (3)	−0.06732 (9)	0.0270 (6)
N2C	0.07011 (13)	−0.0351 (4)	−0.10183 (10)	0.0237 (7)
C1C	0.13030 (15)	−0.1792 (5)	−0.03545 (12)	0.0194 (8)
C2C	0.08732 (15)	−0.1879 (5)	−0.08250 (12)	0.0175 (7)
C3C	0.06764 (15)	−0.3507 (5)	−0.10343 (12)	0.0194 (8)
C4C	0.08984 (17)	−0.4906 (5)	−0.07641 (13)	0.0254 (9)
H4CA	0.0762	−0.5999	−0.0894	0.031*
C5C	0.13326 (16)	−0.4799 (5)	−0.02887 (13)	0.0243 (8)
H5CA	0.1476	−0.5821	−0.0113	0.029*
C6C	0.15429 (15)	−0.3285 (5)	−0.00829 (12)	0.0212 (8)
Br3C	0.012217 (17)	−0.35598 (5)	−0.166822 (13)	0.02888 (10)
Br6C	0.214089 (17)	−0.31864 (5)	0.052689 (13)	0.02804 (10)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1A	0.0222 (17)	0.0171 (17)	0.0236 (16)	−0.0010 (13)	0.0024 (13)	0.0011 (14)
O1A	0.0328 (16)	0.0194 (14)	0.0308 (14)	0.0020 (12)	−0.0004 (12)	0.0071 (12)
O2A	0.0330 (16)	0.0172 (14)	0.0232 (13)	−0.0029 (11)	−0.0028 (12)	−0.0002 (11)
N2A	0.0271 (18)	0.0204 (18)	0.0241 (16)	0.0002 (14)	0.0006 (14)	0.0026 (13)
C1A	0.0192 (18)	0.0155 (19)	0.0162 (17)	−0.0007 (15)	0.0058 (14)	−0.0018 (14)
C2A	0.0210 (19)	0.016 (2)	0.0212 (18)	−0.0005 (15)	0.0055 (15)	−0.0019 (15)
C3A	0.0213 (19)	0.024 (2)	0.0150 (17)	0.0043 (15)	0.0044 (15)	0.0022 (15)
C4A	0.029 (2)	0.016 (2)	0.029 (2)	0.0060 (17)	0.0072 (17)	0.0043 (17)
C5A	0.029 (2)	0.020 (2)	0.026 (2)	−0.0038 (16)	0.0043 (17)	−0.0044 (16)
C6A	0.0196 (19)	0.023 (2)	0.0162 (17)	0.0006 (15)	0.0046 (15)	−0.0016 (15)
Br3A	0.0238 (2)	0.0306 (2)	0.02159 (19)	0.00557 (17)	0.00312 (15)	0.00711 (16)
Br6A	0.0237 (2)	0.0274 (2)	0.01940 (18)	−0.00054 (16)	−0.00028 (15)	0.00022 (15)
N1B	0.0196 (16)	0.0240 (19)	0.0167 (15)	0.0010 (13)	0.0008 (12)	0.0025 (13)
O1B	0.0318 (16)	0.0201 (15)	0.0241 (14)	−0.0032 (12)	−0.0011 (12)	−0.0061 (11)
O2B	0.0335 (15)	0.0162 (14)	0.0247 (13)	0.0021 (11)	−0.0035 (11)	0.0037 (11)
N2B	0.0245 (17)	0.0176 (17)	0.0218 (16)	−0.0006 (13)	−0.0008 (13)	−0.0016 (13)
C1B	0.0198 (19)	0.0103 (18)	0.0222 (18)	−0.0032 (14)	0.0051 (15)	−0.0046 (14)
C2B	0.0152 (19)	0.020 (2)	0.0186 (17)	0.0006 (15)	0.0067 (14)	−0.0004 (14)
C3B	0.0195 (19)	0.023 (2)	0.024 (2)	−0.0018 (16)	0.0056 (16)	−0.0031 (16)
C4B	0.032 (2)	0.019 (2)	0.032 (2)	−0.0043 (17)	0.0106 (18)	−0.0044 (17)
C5B	0.030 (2)	0.017 (2)	0.0257 (19)	0.0021 (17)	0.0032 (17)	0.0073 (16)
C6B	0.0191 (19)	0.017 (2)	0.0195 (17)	−0.0005 (15)	0.0029 (15)	−0.0024 (15)
Br3B	0.0256 (2)	0.0327 (2)	0.02414 (19)	−0.00511 (17)	0.00251 (16)	−0.00977 (17)
Br6B	0.0240 (2)	0.0295 (2)	0.01888 (17)	0.00371 (16)	−0.00068 (15)	−0.00004 (16)
N1C	0.0242 (17)	0.0250 (18)	0.0163 (15)	−0.0030 (14)	0.0022 (13)	−0.0007 (14)
O1C	0.0389 (18)	0.0309 (17)	0.0277 (15)	−0.0086 (13)	−0.0055 (13)	−0.0068 (12)
O2C	0.0340 (16)	0.0172 (14)	0.0246 (14)	0.0002 (12)	−0.0012 (12)	0.0022 (11)
N2C	0.0278 (18)	0.0220 (17)	0.0189 (15)	−0.0012 (14)	0.0021 (13)	−0.0023 (13)
C1C	0.0185 (19)	0.021 (2)	0.0174 (17)	0.0001 (16)	0.0022 (15)	0.0012 (15)
C2C	0.0163 (18)	0.018 (2)	0.0191 (17)	0.0029 (15)	0.0067 (14)	0.0030 (15)
C3C	0.0150 (18)	0.025 (2)	0.0187 (17)	−0.0020 (15)	0.0045 (14)	−0.0023 (15)
C4C	0.030 (2)	0.020 (2)	0.025 (2)	0.0001 (17)	0.0053 (16)	0.0006 (16)
C5C	0.027 (2)	0.024 (2)	0.0218 (19)	0.0046 (17)	0.0061 (16)	0.0067 (16)
C6C	0.0182 (19)	0.026 (2)	0.0171 (17)	0.0023 (16)	0.0007 (15)	0.0018 (16)
Br3C	0.0280 (2)	0.0325 (2)	0.02113 (18)	−0.00316 (17)	−0.00239 (15)	−0.00203 (16)
Br6C	0.0216 (2)	0.0404 (2)	0.01879 (18)	0.00137 (18)	−0.00046 (15)	0.00482 (17)

Geometric parameters (Å, º)

N1A—O1A	1.229 (3)	C3B—C4B	1.352 (5)
N1A—C1A	1.340 (5)	C3B—Br3B	1.883 (3)
N1A—O2A	1.447 (4)	C4B—C5B	1.430 (5)
O2A—N2A	1.387 (4)	C4B—H4BA	0.9500
N2A—C2A	1.314 (4)	C5B—C6B	1.346 (5)
C1A—C2A	1.422 (5)	C5B—H5BA	0.9500
C1A—C6A	1.426 (5)	C6B—Br6B	1.882 (3)
C2A—C3A	1.431 (5)	N1C—O1C	1.226 (4)
C3A—C4A	1.345 (5)	N1C—C1C	1.336 (5)
C3A—Br3A	1.885 (3)	N1C—O2C	1.461 (4)
C4A—C5A	1.435 (5)	O2C—N2C	1.372 (4)
C4A—H4AA	0.9500	N2C—C2C	1.329 (4)
C5A—C6A	1.351 (5)	C1C—C2C	1.416 (4)
C5A—H5AA	0.9500	C1C—C6C	1.422 (5)
C6A—Br6A	1.880 (3)	C2C—C3C	1.425 (5)
N1B—O1B	1.224 (3)	C3C—C4C	1.350 (5)
N1B—C1B	1.341 (4)	C3C—Br3C	1.881 (3)
N1B—O2B	1.466 (3)	C4C—C5C	1.431 (5)
O2B—N2B	1.378 (4)	C4C—H4CA	0.9500
N2B—C2B	1.317 (4)	C5C—C6C	1.349 (5)
C1B—C6B	1.417 (5)	C5C—H5CA	0.9500
C1B—C2B	1.418 (4)	C6C—Br6C	1.878 (3)
C2B—C3B	1.423 (5)
O1A—N1A—C1A	136.5 (3)	C4B—C3B—Br3B	122.6 (3)
O1A—N1A—O2A	117.3 (3)	C2B—C3B—Br3B	119.5 (3)
C1A—N1A—O2A	106.2 (3)	C3B—C4B—C5B	122.0 (3)
N2A—O2A—N1A	109.2 (2)	C3B—C4B—H4BA	119.0
C2A—N2A—O2A	105.4 (3)	C5B—C4B—H4BA	119.0
N1A—C1A—C2A	106.6 (3)	C6B—C5B—C4B	122.4 (3)
N1A—C1A—C6A	131.0 (3)	C6B—C5B—H5BA	118.8
C2A—C1A—C6A	122.4 (3)	C4B—C5B—H5BA	118.8
N2A—C2A—C1A	112.6 (3)	C5B—C6B—C1B	116.1 (3)
N2A—C2A—C3A	128.8 (3)	C5B—C6B—Br6B	122.8 (3)
C1A—C2A—C3A	118.6 (3)	C1B—C6B—Br6B	121.0 (3)
C4A—C3A—C2A	118.1 (3)	O1C—N1C—C1C	136.5 (3)
C4A—C3A—Br3A	122.6 (3)	O1C—N1C—O2C	117.5 (3)
C2A—C3A—Br3A	119.2 (3)	C1C—N1C—O2C	106.0 (3)
C3A—C4A—C5A	122.4 (3)	N2C—O2C—N1C	109.6 (2)
C3A—C4A—H4AA	118.8	C2C—N2C—O2C	104.9 (3)
C5A—C4A—H4AA	118.8	N1C—C1C—C2C	106.5 (3)
C6A—C5A—C4A	122.0 (3)	N1C—C1C—C6C	131.6 (3)
C6A—C5A—H5AA	119.0	C2C—C1C—C6C	121.9 (3)
C4A—C5A—H5AA	119.0	N2C—C2C—C1C	113.0 (3)
C5A—C6A—C1A	116.4 (3)	N2C—C2C—C3C	127.8 (3)
C5A—C6A—Br6A	122.9 (3)	C1C—C2C—C3C	119.2 (3)
C1A—C6A—Br6A	120.7 (3)	C4C—C3C—C2C	117.9 (3)
O1B—N1B—C1B	137.1 (3)	C4C—C3C—Br3C	124.4 (3)
O1B—N1B—O2B	117.3 (3)	C2C—C3C—Br3C	117.7 (3)
C1B—N1B—O2B	105.5 (3)	C3C—C4C—C5C	122.3 (4)
N2B—O2B—N1B	109.3 (2)	C3C—C4C—H4CA	118.9
C2B—N2B—O2B	105.4 (3)	C5C—C4C—H4CA	118.9
N1B—C1B—C6B	130.4 (3)	C6C—C5C—C4C	121.8 (3)
N1B—C1B—C2B	106.8 (3)	C6C—C5C—H5CA	119.1
C6B—C1B—C2B	122.8 (3)	C4C—C5C—H5CA	119.1
N2B—C2B—C1B	112.9 (3)	C5C—C6C—C1C	116.9 (3)
N2B—C2B—C3B	128.3 (3)	C5C—C6C—Br6C	120.8 (3)
C1B—C2B—C3B	118.7 (3)	C1C—C6C—Br6C	122.2 (3)
C4B—C3B—C2B	117.9 (3)