2-(2,4-Di­bromo­phenyl­amino)-7-nitro­benzisoselenazol-3-one

The crystal structure determination of the title compound, C₁₃H₇Br₂N₃O₃Se, was undertaken in the course of a study on 1,2-benzoselenazin-4-one heterocycle homologues of ebselen, a well known anti-oxidizing agent. It allowed unambiguous identification of the molecular formula of the compound. The Br atom in the 4 position is split into two sites with occupation factors of 55 and 45%. The dihedral angle between the phenyl and benzisoselenazole mean planes is 85.0 (5)°. Analysis of the crystal packing shows infinite chains of mol­ecules along the b axis, linked together by an N—H...O intermolecular hydrogen bond.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.005 Å
• Disorder in main residue
• R factor = 0.033
• wR factor = 0.085
• Data-to-parameter ratio = 14.4

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

General Notes



ABSTM_02  When printed, the submitted absorption T values will be replaced
          by the scaled T values. Since the ratio of scaled T's is
          identical to the ratio of reported T values, the scaling does
          not imply a change to the absorption corrections used in the
          study.
          Ratio of Tmax expected/reported      0.594
          Tmax scaled      0.232 Tmin scaled      0.071

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Computing details

Data collection: CAD-4 EXPRESS (Enraf-Nonius, 1992); cell refinement: CAD-4 EXPRESS; data reduction: HELENA (Spek, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and Mercury 1.1 (Bruno et al., 2002); software used to prepare material for publication: SHELXL97.

2-(2,4-Dibromophenylamino)-7-nitrobenzisoselenazol-3-one

Crystal data

C13H7Br2N3O3Se	F(000) = 1872
Mr = 492.00	Dx = 2.170 Mg m^−3
Orthorhombic, Pbca	Cu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 25 reflections
a = 13.8685 (10) Å	θ = 30–42°
b = 8.6075 (10) Å	µ = 9.75 mm^−1
c = 25.233 (2) Å	T = 293 K
V = 3012.1 (5) Å^3	Prism, orange
Z = 8	0.30 × 0.25 × 0.15 mm

Data collection

Enraf-Nonius CAD-4 diffractometer	2634 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.022
Graphite monochromator	θmax = 74.2°, θmin = 3.5°
θ/2θ scans	h = −17→10
Absorption correction: ψ scan (North et al., 1968)	k = 0→10
Tmin = 0.12, Tmax = 0.39	l = 0→31
3587 measured reflections	3 standard reflections every 200 reflections
3075 independent reflections	intensity decay: 4%

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) = 0.085	H atoms treated by a mixture of independent and constrained refinement
S = 1.10	w = 1/[σ^2(Fo^2) + (0.0307P)^2 + 4.0625P] where P = (Fo^2 + 2Fc^2)/3
3075 reflections	(Δ/σ)max = 0.001
213 parameters	Δρmax = 0.44 e Å^−3
65 restraints	Δρmin = −0.48 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
Br1	0.45930 (3)	−0.43090 (5)	0.685078 (19)	0.05383 (13)
Se1	0.07210 (3)	−0.55331 (5)	0.625799 (16)	0.04735 (12)
O1	−0.1873 (2)	−0.6805 (5)	0.53508 (13)	0.0817 (11)
O2	−0.0802 (2)	−0.7089 (4)	0.59704 (14)	0.0754 (10)
O3	0.1866 (2)	−0.1479 (3)	0.58398 (12)	0.0601 (7)
N1	−0.1204 (2)	−0.6321 (5)	0.56236 (14)	0.0573 (9)
N2	0.1609 (2)	−0.3858 (4)	0.62195 (13)	0.0458 (7)
N3	0.2508 (2)	−0.3935 (4)	0.64584 (14)	0.0586 (9)
C1	0.0009 (2)	−0.4341 (4)	0.57868 (13)	0.0363 (7)
C2	−0.0842 (2)	−0.4770 (5)	0.55293 (14)	0.0437 (8)
C3	−0.1287 (3)	−0.3774 (6)	0.51788 (15)	0.0558 (10)
H3	−0.1855	−0.4066	0.5011	0.067*
C4	−0.0886 (3)	−0.2354 (6)	0.50804 (18)	0.0642 (11)
H4	−0.1192	−0.1669	0.4851	0.077*
C5	−0.0030 (3)	−0.1925 (5)	0.53181 (17)	0.0594 (10)
H5	0.0243	−0.0964	0.5243	0.071*
C6	0.0419 (2)	−0.2927 (4)	0.56680 (13)	0.0393 (7)
C7	0.1369 (2)	−0.2630 (4)	0.59101 (14)	0.0405 (7)
C8	0.2624 (2)	−0.3346 (4)	0.69654 (14)	0.0385 (7)
C9	0.3540 (2)	−0.3362 (4)	0.71998 (14)	0.0409 (7)
C10	0.3698 (3)	−0.2662 (5)	0.76868 (14)	0.0501 (9)
H10	0.4310	−0.2674	0.7838	0.060*
C11	0.2948 (3)	−0.1954 (5)	0.79452 (14)	0.0527 (10)
C12	0.2028 (3)	−0.1971 (5)	0.77336 (15)	0.0502 (9)
H12	0.1518	−0.1527	0.7918	0.060*
Br2A	0.3242 (5)	−0.1240 (5)	0.8616 (2)	0.0771 (11)	0.45
Br2B	0.3151 (4)	−0.0715 (4)	0.85772 (16)	0.0672 (7)	0.55
C13	0.1874 (2)	−0.2655 (5)	0.72455 (15)	0.0480 (9)
H13	0.1256	−0.2652	0.7101	0.058*
H30	0.291 (3)	−0.467 (5)	0.6308 (16)	0.058*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br1	0.02708 (18)	0.0583 (2)	0.0761 (3)	0.00395 (16)	−0.00502 (16)	0.0083 (2)
Se1	0.0446 (2)	0.0488 (2)	0.0487 (2)	−0.00418 (17)	−0.01372 (16)	0.00696 (17)
O1	0.0478 (17)	0.125 (3)	0.072 (2)	−0.0382 (19)	−0.0014 (15)	−0.020 (2)
O2	0.063 (2)	0.082 (2)	0.081 (2)	−0.0313 (18)	−0.0076 (17)	0.0169 (18)
O3	0.0548 (16)	0.0492 (16)	0.0762 (19)	−0.0142 (13)	0.0011 (14)	−0.0121 (14)
N1	0.0331 (15)	0.088 (2)	0.0507 (18)	−0.0208 (17)	0.0038 (13)	−0.0099 (18)
N2	0.0313 (14)	0.0482 (16)	0.0577 (18)	0.0024 (13)	−0.0180 (13)	−0.0089 (14)
N3	0.0340 (15)	0.068 (2)	0.074 (2)	0.0170 (15)	−0.0253 (16)	−0.0301 (18)
C1	0.0244 (14)	0.0490 (18)	0.0354 (15)	0.0050 (13)	−0.0006 (12)	−0.0061 (14)
C2	0.0255 (15)	0.067 (2)	0.0382 (17)	−0.0043 (15)	0.0018 (13)	−0.0097 (16)
C3	0.0278 (16)	0.094 (3)	0.045 (2)	0.0135 (18)	−0.0074 (14)	−0.012 (2)
C4	0.051 (2)	0.080 (3)	0.062 (3)	0.024 (2)	−0.015 (2)	0.008 (2)
C5	0.055 (2)	0.053 (2)	0.070 (3)	0.0130 (19)	−0.007 (2)	0.010 (2)
C6	0.0294 (15)	0.0456 (18)	0.0431 (18)	0.0087 (13)	−0.0020 (13)	−0.0034 (15)
C7	0.0357 (16)	0.0400 (17)	0.0459 (18)	0.0015 (14)	−0.0009 (14)	−0.0126 (15)
C8	0.0281 (15)	0.0372 (16)	0.0503 (18)	0.0005 (13)	−0.0115 (13)	0.0016 (14)
C9	0.0260 (15)	0.0439 (18)	0.0528 (19)	−0.0031 (13)	−0.0094 (13)	0.0113 (15)
C10	0.0321 (16)	0.071 (3)	0.0471 (19)	−0.0104 (17)	−0.0117 (14)	0.0100 (17)
C11	0.0451 (19)	0.077 (3)	0.0365 (17)	−0.0180 (19)	−0.0042 (15)	0.0106 (17)
C12	0.0399 (18)	0.064 (2)	0.0463 (19)	−0.0043 (17)	0.0004 (15)	0.0035 (17)
Br2A	0.0633 (11)	0.132 (3)	0.0358 (8)	−0.015 (2)	−0.0064 (6)	−0.0004 (18)
Br2B	0.0652 (13)	0.1006 (17)	0.0357 (9)	−0.0211 (13)	0.0009 (7)	−0.0066 (10)
C13	0.0288 (16)	0.059 (2)	0.057 (2)	0.0021 (16)	−0.0102 (14)	0.0000 (18)

Geometric parameters (Å, º)

Br1—C9	1.890 (4)	C3—C4	1.365 (7)
Se1—C1	1.855 (3)	C4—C5	1.380 (6)
Se1—N2	1.899 (3)	C5—C6	1.382 (5)
O1—N1	1.228 (4)	C6—C7	1.475 (4)
O2—N1	1.230 (5)	C8—C13	1.392 (5)
O3—C7	1.220 (4)	C8—C9	1.401 (4)
N1—C2	1.446 (5)	C9—C10	1.386 (5)
N2—C7	1.355 (5)	C10—C11	1.370 (6)
N2—N3	1.386 (4)	C11—C12	1.383 (5)
N3—C8	1.385 (5)	C11—Br2A	1.847 (6)
C1—C6	1.376 (5)	C11—Br2B	1.939 (6)
C1—C2	1.397 (4)	C12—C13	1.382 (5)
C2—C3	1.377 (6)
C1—Se1—N2	83.82 (14)	C5—C6—C7	124.0 (4)
O1—N1—O2	123.9 (4)	O3—C7—N2	125.3 (3)
O1—N1—C2	118.9 (4)	O3—C7—C6	125.8 (3)
O2—N1—C2	117.1 (3)	N2—C7—C6	108.9 (3)
C7—N2—N3	120.6 (3)	N3—C8—C13	122.6 (3)
C7—N2—Se1	117.5 (2)	N3—C8—C9	119.5 (3)
N3—N2—Se1	121.6 (3)	C13—C8—C9	117.9 (3)
C8—N3—N2	119.3 (3)	C10—C9—C8	120.9 (3)
C6—C1—C2	118.8 (3)	C10—C9—Br1	118.6 (2)
C6—C1—Se1	114.2 (2)	C8—C9—Br1	120.5 (3)
C2—C1—Se1	127.0 (3)	C11—C10—C9	119.7 (3)
C3—C2—C1	120.8 (4)	C10—C11—C12	120.7 (4)
C3—C2—N1	121.7 (3)	C10—C11—Br2A	114.6 (3)
C1—C2—N1	117.4 (3)	C12—C11—Br2A	124.1 (4)
C4—C3—C2	119.4 (4)	C10—C11—Br2B	121.7 (3)
C3—C4—C5	120.7 (4)	C12—C11—Br2B	117.2 (4)
C4—C5—C6	119.9 (4)	Br2A—C11—Br2B	14.3 (2)
C1—C6—C5	120.3 (3)	C13—C12—C11	119.5 (4)
C1—C6—C7	115.6 (3)	C12—C13—C8	121.2 (3)
C1—Se1—N2—C7	1.2 (3)	Se1—N2—N3—C8	−93.8 (4)
C1—Se1—N2—N3	−173.1 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N3—H30···O3^i	0.93 (4)	1.98 (4)	2.826 (4)	151 (4)

Symmetry code: (i) −x+1/2, y−1/2, z.