5,6-Di­bromo-1H-indole-2,3-dione

Golen, J.A.; Manke, D.R.

doi:10.1107/S2414314617003558

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 2| Part 3| March 2017| x170355

https://doi.org/10.1107/S2414314617003558

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5,6-Dibromo-1H-indole-2,3-dione

James A. Golen ^a and David R. Manke ^a ^*

^aDepartment of Chemistry and Biochemistry, University of Massachusetts Dartmouth, 285 Old Westport Road, North Dartmouth, MA 02747, USA
^*Correspondence e-mail: dmanke@umassd.edu

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 25 February 2017; accepted 4 March 2017; online 10 March 2017)

The title compound, C₈H₃Br₂NO₂, crystallizes with two near planar molecules in the asymmetric unit, with non-H atoms possessing mean deviations from planarity of 0.012 and 0.014 Å. The two molecules are connected by an N—H⋯O and a C—H⋯O hydrogen bond. In the crystal, molecules connect through a series of bifurcated N—(H,H)⋯O hydrogen bonds, forming chains propagating along the [1-1-1] direction. The molecules are further linked through intermolecular halogen interactions, including a Br⋯O close contact of 2.9409 (3) Å, and two C—H⋯Br interactions of 3.777 (3) and 3.845 (3) Å. These interactions link the chains into sheets lying parallel to the (1-23) plane.

Keywords: crystal structure; isatins; hydrogen bonding; halogen–oxygen interactions.

CCDC reference: 1536015

Structure description

In our continued efforts to study the interactions of halogenated isatins in the solid state, we report herein on the crystal structure of the title compound, 5,6-dibromoisatin (Fig. 1). There are two molecules in the asymmetric unit, both are nearly planar, with the non-hydrogen atoms possessing mean deviations from planarity of 0.012 and 0.014 Å. The two molecules are connected by an N—H⋯O and a C—H⋯O hydrogen bond (Table 1). The geometrical parameters of the isatin molecules are similar to those observed in the parent compound (Goldschmidt & Llewellyn, 1950 ). Of note in the structure are Br2⋯O2 close contacts of 2.9409 (3) Å, with the bromine substituted at the 6 position of the isatin ring. In previous reports, 6-bromoisatin (Turbitt et al., 2016 ) was found to have a similar interaction, which was also observed in 4-bromoisatin (Huang et al., 2016 ) and 7-bromoisatin (Golen & Manke, 2016a ). Interestingly, Br1, which is at the 5-position of the isatin is not involved in a Br⋯O interaction. This was also not present in the solid state structure of 5-bromoisatin (Gurung et al., 2016 ). For comparison, I⋯O close contacts were observed for both 5-iodoisatin (Garden et al., 2006 ) and 6-iodoisatin (Golen & Manke, 2016b ).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O1Aⁱ	0.86 (2)	2.34 (3)	2.979 (3)	132 (3)
N1—H1⋯O2Aⁱ	0.86 (2)	2.40 (2)	3.191 (3)	153 (3)
N1A—H1A⋯O1Aⁱ	0.86 (2)	2.40 (2)	3.109 (3)	140 (3)
N1A—H1A⋯O1	0.86 (2)	2.13 (2)	2.835 (3)	140 (3)
C7A—H7A⋯O1	0.95	2.31	3.039 (3)	133
C4—H4⋯Br2Aⁱⁱ	0.95	3.03	3.845 (3)	145
C4A—H4A⋯Br1ⁱⁱⁱ	0.95	2.94	3.777 (3)	147
Symmetry codes: (i) -x+2, -y+1, -z+1; (ii) -x, -y, -z+1; (iii) x+1, y-1, z-1.

Figure 1
The molecular structure of the two independent molecules of the title compound, showing the atom labelling. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen bonds are shown as dashed lines (see Table 1

In the crystal, molecules combine through bifurcated N—(H,H)⋯O hydrogen bonds (Table 1), resulting in infinite chains along [1 $[\overline{1}]$ $[\overline{1}]$ ]. The molecules are further linked through a C—H⋯O hydrogen bond, two C—H⋯Br interactions and the aforementioned Br⋯O interaction, to yield infinite sheets lying parallel to (1 $[\overline{2}]$ 3); see Table 1 and Fig. 2.

Figure 2
The crystal packing of the title compound, viewed along the a axis. The N—H⋯O and C—H⋯Br hydrogen bonds and O⋯Br interactions are shown as dashed lines (see Table 1

Synthesis and crystallization

A commercial sample (AK Scientific) of 5,6-dibromo-1H-indole-2,3-dione was used for crystallization. Orange block-like crystals were grown by slow evaporation of a solution in tetrahydrofuran.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₈H₃Br₂NO₂
M_r	304.93
Crystal system, space group	Triclinic, P $[\overline{1}]$
Temperature (K)	200
a, b, c (Å)	7.1044 (10), 10.5317 (15), 12.2598 (17)
α, β, γ (°)	108.078 (4), 93.481 (5), 101.484 (4)
V (Å³)	847.1 (2)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	9.53
Crystal size (mm)	0.18 × 0.07 × 0.05

Data collection
Diffractometer	Bruker D8 Venture CMOS
Absorption correction	Multi-scan (SADABS; Bruker, 2014 )
T_min, T_max	0.147, 0.259
No. of measured, independent and observed [I > 2σ(I)] reflections	23591, 3116, 2728
R_int	0.037
(sin θ/λ)_max (Å⁻¹)	0.603

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.020, 0.047, 1.04
No. of reflections	3116
No. of parameters	241
No. of restraints	2
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.38, −0.59
Computer programs: APEX2 and SAINT (Bruker, 2014), SHELXS97 (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), OLEX2 (Dolomanov et al., 2009 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 1536015

Crystal structure: contains datablocks Global, I. DOI: https://doi.org/10.1107/S2414314617003558/su4137sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617003558/su4137Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314617003558/su4137Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2014); cell refinement: SAINT (Bruker, 2014); data reduction: SAINT (Bruker, 2014); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: publCIF (Westrip, 2010).

5,6-Dibromo-1H-indole-2,3-dione top

Crystal data top

C₈H₃Br₂NO₂	Z = 4
M_r = 304.93	F(000) = 576
Triclinic, P1	D_x = 2.391 Mg m⁻³
a = 7.1044 (10) Å	Mo Kα radiation, λ = 0.71073 Å
b = 10.5317 (15) Å	Cell parameters from 9890 reflections
c = 12.2598 (17) Å	θ = 3.2–25.4°
α = 108.078 (4)°	µ = 9.53 mm⁻¹
β = 93.481 (5)°	T = 200 K
γ = 101.484 (4)°	Block, orange
V = 847.1 (2) Å³	0.18 × 0.07 × 0.05 mm

Data collection top

Bruker D8 Venture CMOS diffractometer	2728 reflections with I > 2σ(I)
φ and ω scans	R_int = 0.037
Absorption correction: multi-scan (SADABS; Bruker, 2014)	θ_max = 25.4°, θ_min = 3.0°
T_min = 0.147, T_max = 0.259	h = −8→8
23591 measured reflections	k = −12→12
3116 independent reflections	l = −14→14

Refinement top

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)] = 0.020	Hydrogen site location: mixed
wR(F²) = 0.047	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ²(F_o²) + (0.020P)² + 0.9509P] where P = (F_o² + 2F_c²)/3
3116 reflections	(Δ/σ)_max = 0.001
241 parameters	Δρ_max = 0.38 e Å⁻³
2 restraints	Δρ_min = −0.59 e Å⁻³

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Br1A	0.47270 (4)	−0.30752 (3)	0.14714 (2)	0.02479 (8)
Br2A	0.22006 (4)	−0.12973 (3)	0.33501 (2)	0.02340 (8)
O1A	1.1378 (3)	0.4127 (2)	0.42202 (19)	0.0299 (5)
O2A	1.1634 (3)	0.1601 (2)	0.24850 (18)	0.0280 (5)
N1A	0.8347 (3)	0.2843 (2)	0.4282 (2)	0.0203 (5)
H1A	0.790 (4)	0.344 (3)	0.478 (2)	0.024*
C1A	1.0112 (4)	0.3079 (3)	0.3919 (2)	0.0207 (6)
C2A	1.0237 (4)	0.1715 (3)	0.2994 (2)	0.0191 (6)
C3A	0.8391 (4)	0.0758 (3)	0.2929 (2)	0.0181 (6)
C4A	0.7644 (4)	−0.0600 (3)	0.2257 (2)	0.0198 (6)
H4A	0.8380	−0.1092	0.1729	0.024*
C5A	0.5791 (4)	−0.1220 (3)	0.2376 (2)	0.0201 (6)
C6A	0.4717 (4)	−0.0480 (3)	0.3155 (2)	0.0187 (6)
C7A	0.5464 (4)	0.0886 (3)	0.3829 (2)	0.0196 (6)
H7A	0.4728	0.1384	0.4354	0.023*
C8A	0.7306 (4)	0.1485 (3)	0.3706 (2)	0.0176 (6)
Br1	−0.16323 (4)	0.65214 (3)	0.96887 (3)	0.03334 (9)
Br2	0.21559 (4)	0.91557 (3)	1.01670 (3)	0.02740 (8)
O1	0.5314 (3)	0.3653 (2)	0.55313 (19)	0.0328 (5)
O2	0.1546 (3)	0.2594 (2)	0.61325 (18)	0.0280 (5)
N1	0.5037 (3)	0.5666 (2)	0.6916 (2)	0.0225 (5)
H1	0.609 (3)	0.621 (3)	0.690 (3)	0.027*
C1	0.4470 (4)	0.4324 (3)	0.6242 (2)	0.0219 (6)
C2	0.2460 (4)	0.3766 (3)	0.6564 (2)	0.0205 (6)
C3	0.2055 (4)	0.4942 (3)	0.7454 (2)	0.0197 (6)
C4	0.0484 (4)	0.5079 (3)	0.8054 (2)	0.0218 (6)
H4	−0.0593	0.4326	0.7917	0.026*
C5	0.0522 (4)	0.6344 (3)	0.8861 (2)	0.0225 (6)
C6	0.2115 (4)	0.7443 (3)	0.9055 (2)	0.0205 (6)
C7	0.3705 (4)	0.7315 (3)	0.8445 (2)	0.0209 (6)
H7	0.4782	0.8066	0.8576	0.025*
C8	0.3639 (4)	0.6048 (3)	0.7644 (2)	0.0184 (6)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1A	0.02325 (15)	0.01670 (14)	0.02779 (16)	0.00039 (11)	0.00439 (11)	0.00042 (12)
Br2A	0.01509 (14)	0.02296 (15)	0.02782 (16)	−0.00174 (11)	0.00595 (11)	0.00550 (12)
O1A	0.0210 (10)	0.0198 (11)	0.0399 (13)	−0.0048 (9)	0.0090 (9)	0.0023 (10)
O2A	0.0210 (10)	0.0254 (11)	0.0353 (12)	0.0038 (8)	0.0126 (9)	0.0060 (9)
N1A	0.0179 (11)	0.0143 (11)	0.0233 (12)	0.0014 (9)	0.0079 (9)	−0.0007 (10)
C1A	0.0167 (13)	0.0196 (14)	0.0247 (15)	0.0027 (11)	0.0032 (11)	0.0065 (12)
C2A	0.0164 (13)	0.0180 (14)	0.0235 (14)	0.0041 (11)	0.0050 (11)	0.0074 (12)
C3A	0.0158 (13)	0.0171 (13)	0.0215 (14)	0.0040 (10)	0.0048 (11)	0.0060 (11)
C4A	0.0186 (13)	0.0195 (14)	0.0203 (14)	0.0049 (11)	0.0063 (11)	0.0041 (12)
C5A	0.0214 (14)	0.0161 (13)	0.0203 (14)	0.0021 (11)	0.0017 (11)	0.0040 (11)
C6A	0.0129 (13)	0.0216 (14)	0.0209 (14)	0.0010 (10)	0.0027 (10)	0.0080 (12)
C7A	0.0176 (13)	0.0201 (14)	0.0199 (14)	0.0048 (11)	0.0057 (11)	0.0042 (12)
C8A	0.0165 (13)	0.0161 (13)	0.0178 (13)	0.0010 (10)	0.0010 (10)	0.0043 (11)
Br1	0.02592 (16)	0.02957 (17)	0.03630 (18)	0.00441 (12)	0.01712 (13)	−0.00192 (14)
Br2	0.02990 (16)	0.01911 (15)	0.02697 (16)	0.00648 (12)	0.00552 (12)	−0.00201 (12)
O1	0.0263 (11)	0.0239 (11)	0.0409 (13)	0.0033 (9)	0.0188 (10)	−0.0007 (10)
O2	0.0247 (11)	0.0195 (11)	0.0319 (12)	−0.0005 (8)	0.0086 (9)	−0.0001 (9)
N1	0.0173 (12)	0.0180 (12)	0.0272 (13)	0.0000 (9)	0.0101 (10)	0.0015 (10)
C1	0.0186 (14)	0.0200 (14)	0.0249 (15)	0.0029 (11)	0.0081 (12)	0.0042 (12)
C2	0.0177 (13)	0.0213 (15)	0.0212 (14)	0.0032 (11)	0.0044 (11)	0.0055 (12)
C3	0.0195 (14)	0.0169 (14)	0.0210 (14)	0.0031 (11)	0.0049 (11)	0.0041 (12)
C4	0.0182 (14)	0.0212 (14)	0.0235 (15)	0.0009 (11)	0.0044 (11)	0.0059 (12)
C5	0.0182 (14)	0.0260 (15)	0.0226 (14)	0.0078 (11)	0.0072 (11)	0.0046 (12)
C6	0.0243 (14)	0.0181 (13)	0.0173 (13)	0.0070 (11)	0.0009 (11)	0.0024 (11)
C7	0.0198 (14)	0.0176 (14)	0.0233 (14)	0.0009 (11)	0.0026 (11)	0.0061 (12)
C8	0.0160 (13)	0.0204 (14)	0.0185 (14)	0.0034 (11)	0.0046 (11)	0.0061 (12)

Geometric parameters (Å, º) top

Br1A—C5A	1.893 (3)	Br1—C5	1.895 (3)
Br2A—C6A	1.887 (3)	Br2—C6	1.887 (3)
O1A—C1A	1.214 (3)	O1—C1	1.212 (3)
O2A—C2A	1.210 (3)	O2—C2	1.208 (3)
N1A—H1A	0.855 (17)	N1—H1	0.858 (18)
N1A—C1A	1.358 (3)	N1—C1	1.360 (4)
N1A—C8A	1.407 (3)	N1—C8	1.411 (3)
C1A—C2A	1.553 (4)	C1—C2	1.555 (4)
C2A—C3A	1.467 (4)	C2—C3	1.465 (4)
C3A—C4A	1.385 (4)	C3—C4	1.380 (4)
C3A—C8A	1.400 (4)	C3—C8	1.398 (4)
C4A—H4A	0.9500	C4—H4	0.9500
C4A—C5A	1.386 (4)	C4—C5	1.386 (4)
C5A—C6A	1.402 (4)	C5—C6	1.397 (4)
C6A—C7A	1.392 (4)	C6—C7	1.398 (4)
C7A—H7A	0.9500	C7—H7	0.9500
C7A—C8A	1.374 (4)	C7—C8	1.379 (4)

C1A—N1A—H1A	125 (2)	C1—N1—H1	125 (2)
C1A—N1A—C8A	111.0 (2)	C1—N1—C8	111.0 (2)
C8A—N1A—H1A	124 (2)	C8—N1—H1	124 (2)
O1A—C1A—N1A	129.0 (3)	O1—C1—N1	128.9 (3)
O1A—C1A—C2A	124.7 (2)	O1—C1—C2	124.9 (2)
N1A—C1A—C2A	106.3 (2)	N1—C1—C2	106.2 (2)
O2A—C2A—C1A	122.3 (2)	O2—C2—C1	123.6 (2)
O2A—C2A—C3A	132.8 (3)	O2—C2—C3	131.6 (3)
C3A—C2A—C1A	104.9 (2)	C3—C2—C1	104.8 (2)
C4A—C3A—C2A	132.1 (2)	C4—C3—C2	131.5 (3)
C4A—C3A—C8A	121.0 (2)	C4—C3—C8	121.2 (2)
C8A—C3A—C2A	106.9 (2)	C8—C3—C2	107.3 (2)
C3A—C4A—H4A	120.9	C3—C4—H4	120.9
C3A—C4A—C5A	118.1 (2)	C3—C4—C5	118.1 (3)
C5A—C4A—H4A	120.9	C5—C4—H4	120.9
C4A—C5A—Br1A	119.2 (2)	C4—C5—Br1	117.9 (2)
C4A—C5A—C6A	120.3 (2)	C4—C5—C6	120.4 (3)
C6A—C5A—Br1A	120.5 (2)	C6—C5—Br1	121.7 (2)
C5A—C6A—Br2A	121.4 (2)	C5—C6—Br2	119.9 (2)
C7A—C6A—Br2A	116.9 (2)	C5—C6—C7	121.8 (2)
C7A—C6A—C5A	121.6 (2)	C7—C6—Br2	118.3 (2)
C6A—C7A—H7A	121.3	C6—C7—H7	121.5
C8A—C7A—C6A	117.4 (2)	C8—C7—C6	117.0 (2)
C8A—C7A—H7A	121.3	C8—C7—H7	121.5
C3A—C8A—N1A	110.9 (2)	C3—C8—N1	110.7 (2)
C7A—C8A—N1A	127.6 (2)	C7—C8—N1	127.8 (2)
C7A—C8A—C3A	121.5 (2)	C7—C8—C3	121.5 (2)

Br1A—C5A—C6A—Br2A	0.9 (3)	Br1—C5—C6—Br2	0.1 (4)
Br1A—C5A—C6A—C7A	−179.9 (2)	Br1—C5—C6—C7	−180.0 (2)
Br2A—C6A—C7A—C8A	179.1 (2)	Br2—C6—C7—C8	179.6 (2)
O1A—C1A—C2A—O2A	−0.8 (5)	O1—C1—C2—O2	0.3 (5)
O1A—C1A—C2A—C3A	179.9 (3)	O1—C1—C2—C3	179.8 (3)
O2A—C2A—C3A—C4A	0.0 (6)	O2—C2—C3—C4	−1.7 (6)
O2A—C2A—C3A—C8A	−178.1 (3)	O2—C2—C3—C8	178.7 (3)
N1A—C1A—C2A—O2A	178.5 (3)	N1—C1—C2—O2	−179.1 (3)
N1A—C1A—C2A—C3A	−0.8 (3)	N1—C1—C2—C3	0.3 (3)
C1A—N1A—C8A—C3A	0.5 (3)	C1—N1—C8—C3	−0.7 (3)
C1A—N1A—C8A—C7A	−178.6 (3)	C1—N1—C8—C7	179.8 (3)
C1A—C2A—C3A—C4A	179.2 (3)	C1—C2—C3—C4	179.0 (3)
C1A—C2A—C3A—C8A	1.0 (3)	C1—C2—C3—C8	−0.7 (3)
C2A—C3A—C4A—C5A	−178.0 (3)	C2—C3—C4—C5	179.8 (3)
C2A—C3A—C8A—N1A	−1.0 (3)	C2—C3—C8—N1	0.9 (3)
C2A—C3A—C8A—C7A	178.1 (3)	C2—C3—C8—C7	−179.6 (3)
C3A—C4A—C5A—Br1A	−180.0 (2)	C3—C4—C5—Br1	−179.6 (2)
C3A—C4A—C5A—C6A	0.3 (4)	C3—C4—C5—C6	0.0 (4)
C4A—C3A—C8A—N1A	−179.4 (3)	C4—C3—C8—N1	−178.8 (3)
C4A—C3A—C8A—C7A	−0.3 (4)	C4—C3—C8—C7	0.7 (4)
C4A—C5A—C6A—Br2A	−179.4 (2)	C4—C5—C6—Br2	−179.4 (2)
C4A—C5A—C6A—C7A	−0.2 (4)	C4—C5—C6—C7	0.5 (5)
C5A—C6A—C7A—C8A	−0.2 (4)	C5—C6—C7—C8	−0.4 (4)
C6A—C7A—C8A—N1A	179.3 (3)	C6—C7—C8—N1	179.2 (3)
C6A—C7A—C8A—C3A	0.4 (4)	C6—C7—C8—C3	−0.2 (4)
C8A—N1A—C1A—O1A	179.5 (3)	C8—N1—C1—O1	−179.2 (3)
C8A—N1A—C1A—C2A	0.2 (3)	C8—N1—C1—C2	0.2 (3)
C8A—C3A—C4A—C5A	−0.1 (4)	C8—C3—C4—C5	−0.6 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1Aⁱ	0.86 (2)	2.34 (3)	2.979 (3)	132 (3)
N1—H1···O2Aⁱ	0.86 (2)	2.40 (2)	3.191 (3)	153 (3)
N1A—H1A···O1Aⁱ	0.86 (2)	2.40 (2)	3.109 (3)	140 (3)
N1A—H1A···O1	0.86 (2)	2.13 (2)	2.835 (3)	140 (3)
C7A—H7A···O1	0.95	2.31	3.039 (3)	133
C4—H4···Br2Aⁱⁱ	0.95	3.03	3.845 (3)	145
C4A—H4A···Br1ⁱⁱⁱ	0.95	2.94	3.777 (3)	147

Symmetry codes: (i) −x+2, −y+1, −z+1; (ii) −x, −y, −z+1; (iii) x+1, y−1, z−1.

Funding information

Funding for this research was provided by: National Science Foundation (award No. CHE-1429086).

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