4-Bromo-methyl-7-methyl-6,8-dinitro-coumarin.

The crystal structure of the title compound, C(11)H(7)BrN(2)O(6), establishes the substitution positions of the nitro groups from the nitration reaction of 7-methyl-4-bromo-methyl coumarin. The mean planes of the nitro groups form dihedral angles of 43.9 (8) and 52.7 (10)° with the essentially planar [maximum deviation 0.031 (6) Å] benzopyran ring system.

Related literature

For background information on the nitration of coumarin compounds, see: Kulkarni et al. (1983 ▶); Clayton et al. (1910 ▶). For a related structure, see: Vasudevan et al. (1990 ▶). For ab initio calculations on 6-methyl-4-bromo­methyl­coumarins, see: Sortur et al. (2006 ▶).

Experimental

Crystal data

C11H7BrN2O6

M = 343.09

Orthorhombic,

a = 8.122 (2) Å

b = 11.091 (4) Å

c = 27.723 (6) Å

V = 2497.3 (12) Å3

Z = 8

Mo Kα radiation

μ = 3.32 mm−1

T = 294 K

0.2 × 0.2 × 0.1 mm

Data collection

Enraf–Nonius CAD-4 diffractometer

Absorption correction: ψ scan (North et al., 1968 ▶) T min = 0.520, T max = 0.72

2196 measured reflections

2196 independent reflections

1148 reflections with I > 2σ(I)

2 standard reflections frequency: 60 min intensity decay: none

Refinement

R[F 2 > 2σ(F 2)] = 0.060

wR(F 2) = 0.171

S = 1.05

2196 reflections

182 parameters

H-atom parameters constrained

Δρmax = 0.63 e Å−3

Δρmin = −0.82 e Å−3

Data collection: CAD-4 Software (Enraf–Nonius, 1989 ▶); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995 ▶); program(s) used to solve structure: SIR92 (Altomare et al., 1994 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶); software used to prepare material for publication: SHELXL97.

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053680903596X/lh2864sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053680903596X/lh2864Isup2.hkl

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

C11H7BrN2O6	F(000) = 1360
Mr = 343.09	Dx = 1.825 Mg m−3
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 25 reflections
a = 8.122 (2) Å	θ = 10–15°
b = 11.091 (4) Å	µ = 3.32 mm−1
c = 27.723 (6) Å	T = 294 K
V = 2497.3 (12) Å3	Plate, colourless
Z = 8	0.2 × 0.2 × 0.1 mm

Enraf–Nonius CAD-4 diffractometer	1148 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.0000
graphite	θmax = 25.0°, θmin = 2.9°
ω–2θ scans	h = 0→9
Absorption correction: ψ scan (North et al., 1968)	k = 0→13
Tmin = 0.520, Tmax = 0.72	l = 0→32
2196 measured reflections	2 standard reflections every 60 min
2196 independent reflections	intensity decay: none

Refinement on F2	0 restraints
Least-squares matrix: full	H-atom parameters constrained
R[F2 > 2σ(F2)] = 0.060	w = 1/[σ2(Fo2) + (0.0687P)2 + 11.8667P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.171	(Δ/σ)max = 0.001
S = 1.05	Δρmax = 0.63 e Å−3
2196 reflections	Δρmin = −0.82 e Å−3
182 parameters

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
C1	0.7703 (11)	0.2886 (7)	0.6819 (3)	0.047 (2)
C2	0.9438 (10)	0.2873 (7)	0.6922 (3)	0.045 (2)
H3	0.9856	0.3447	0.7134	0.054*
C3	1.0484 (9)	0.2073 (6)	0.6727 (3)	0.0380 (18)
C4	1.0779 (9)	0.0341 (6)	0.6146 (3)	0.0364 (18)
H5	1.1898	0.0281	0.6213	0.044*
C5	1.0085 (9)	−0.0431 (6)	0.5812 (2)	0.0348 (17)
C6	0.8400 (9)	−0.0445 (6)	0.5709 (3)	0.0395 (19)
C7	0.7498 (9)	0.0406 (6)	0.5954 (2)	0.0358 (16)
C8	0.9860 (8)	0.1194 (6)	0.6381 (3)	0.0326 (17)
C9	0.8194 (9)	0.1222 (6)	0.6280 (3)	0.0339 (17)
C10	1.2259 (10)	0.2058 (7)	0.6867 (3)	0.049 (2)
H11A	1.2542	0.2804	0.7030	0.059*
H11B	1.2942	0.1987	0.6581	0.059*
C11	0.7574 (12)	−0.1318 (7)	0.5373 (3)	0.057 (2)
H12A	0.8385	−0.1842	0.5234	0.085*
H12B	0.7020	−0.0882	0.5122	0.085*
H12C	0.6787	−0.1790	0.5550	0.085*
N1	1.1229 (9)	−0.1278 (6)	0.5564 (3)	0.0483 (17)
N2	0.5699 (8)	0.0459 (6)	0.5897 (3)	0.0477 (17)
O1	0.7146 (6)	0.2044 (4)	0.64815 (18)	0.0406 (13)
O2	0.6689 (8)	0.3553 (6)	0.6980 (2)	0.0649 (18)
O3	1.2252 (9)	−0.1757 (6)	0.5791 (3)	0.085 (2)
O4	1.1032 (9)	−0.1384 (6)	0.5134 (3)	0.079 (2)
O5	0.5137 (9)	0.0940 (7)	0.5564 (3)	0.099 (3)
O6	0.4882 (8)	0.0020 (9)	0.6212 (3)	0.113 (3)
Br	1.26518 (11)	0.06847 (7)	0.72976 (3)	0.0597 (4)

	U11	U22	U33	U12	U13	U23
C1	0.061 (6)	0.043 (4)	0.037 (4)	0.004 (5)	−0.002 (5)	−0.002 (4)
C2	0.060 (6)	0.036 (4)	0.040 (4)	−0.001 (4)	−0.002 (4)	−0.006 (4)
C3	0.040 (4)	0.039 (4)	0.034 (4)	−0.008 (4)	−0.002 (3)	0.004 (3)
C4	0.034 (4)	0.038 (4)	0.038 (4)	0.000 (3)	−0.004 (3)	−0.001 (3)
C5	0.039 (4)	0.036 (4)	0.029 (4)	0.007 (3)	0.003 (3)	−0.002 (3)
C6	0.045 (5)	0.040 (4)	0.034 (4)	−0.003 (4)	−0.009 (4)	0.001 (3)
C7	0.030 (4)	0.039 (4)	0.039 (4)	−0.002 (4)	−0.002 (4)	0.006 (3)
C8	0.028 (4)	0.034 (4)	0.036 (4)	−0.004 (3)	0.000 (3)	−0.003 (3)
C9	0.033 (4)	0.037 (4)	0.032 (4)	0.007 (3)	0.004 (3)	0.005 (3)
C10	0.056 (6)	0.048 (4)	0.044 (4)	−0.013 (4)	−0.004 (4)	−0.001 (4)
C11	0.072 (6)	0.040 (4)	0.058 (5)	−0.001 (5)	−0.024 (5)	−0.011 (4)
N1	0.049 (5)	0.049 (4)	0.045 (5)	0.001 (4)	0.001 (4)	−0.001 (4)
N2	0.037 (4)	0.046 (4)	0.058 (5)	0.001 (3)	−0.012 (4)	0.001 (4)
O1	0.031 (3)	0.049 (3)	0.042 (3)	0.010 (2)	−0.003 (2)	−0.002 (3)
O2	0.071 (4)	0.063 (4)	0.061 (4)	0.026 (4)	0.003 (3)	−0.013 (3)
O3	0.074 (5)	0.092 (5)	0.088 (5)	0.039 (4)	−0.010 (4)	−0.023 (4)
O4	0.102 (6)	0.076 (4)	0.059 (5)	0.023 (4)	0.012 (4)	−0.014 (4)
O5	0.060 (5)	0.130 (7)	0.108 (6)	0.004 (4)	−0.033 (5)	0.048 (5)
O6	0.038 (4)	0.160 (8)	0.141 (8)	−0.011 (5)	−0.002 (5)	0.073 (7)
Br	0.0621 (6)	0.0560 (5)	0.0611 (6)	0.0056 (5)	−0.0181 (5)	−0.0042 (4)

C1—O2	1.194 (9)	C7—C9	1.397 (10)
C1—O1	1.398 (9)	C7—N2	1.471 (10)
C1—C2	1.438 (11)	C8—C9	1.382 (9)
C2—C3	1.342 (10)	C9—O1	1.368 (8)
C2—H3	0.9300	C10—H11A	0.9700
C3—C8	1.458 (10)	C10—H11B	0.9700
C3—C10	1.494 (11)	C11—H12A	0.9600
C4—C8	1.370 (10)	C11—H12B	0.9600
C4—C5	1.383 (9)	C11—H12C	0.9600
C4—H5	0.9300	N1—O3	1.169 (9)
C5—C6	1.398 (10)	N1—O4	1.210 (9)
C5—N1	1.488 (10)	N2—O5	1.160 (8)
C6—C7	1.375 (10)	N2—O6	1.201 (9)
C6—C11	1.501 (10)
O2—C1—O1	116.2 (8)	C9—C8—C3	117.3 (7)
O2—C1—C2	127.4 (8)	O1—C9—C8	122.8 (7)
O1—C1—C2	116.3 (7)	O1—C9—C7	116.4 (6)
C3—C2—C1	123.1 (7)	C8—C9—C7	120.9 (7)
C3—C2—H3	118.4	C3—C10—Br	108.9 (5)
C1—C2—H3	118.4	C3—C10—H11A	109.9
C2—C3—C8	119.2 (7)	Br—C10—H11A	109.9
C2—C3—C10	120.9 (7)	C3—C10—H11B	109.9
C8—C3—C10	120.0 (7)	Br—C10—H11B	109.9
C8—C4—C5	121.6 (7)	H11A—C10—H11B	108.3
C8—C4—H5	119.2	C6—C11—H12A	109.5
C5—C4—H5	119.2	C6—C11—H12B	109.5
C4—C5—C6	122.9 (7)	H12A—C11—H12B	109.5
C4—C5—N1	116.5 (7)	C6—C11—H12C	109.5
C6—C5—N1	120.7 (7)	H12A—C11—H12C	109.5
C7—C6—C5	114.4 (7)	H12B—C11—H12C	109.5
C7—C6—C11	120.8 (7)	O3—N1—O4	125.5 (8)
C5—C6—C11	124.8 (7)	O3—N1—C5	118.9 (7)
C6—C7—C9	123.3 (7)	O4—N1—C5	115.6 (7)
C6—C7—N2	120.2 (7)	O5—N2—O6	123.2 (8)
C9—C7—N2	116.5 (6)	O5—N2—C7	119.7 (8)
C4—C8—C9	116.9 (7)	O6—N2—C7	117.0 (7)
C4—C8—C3	125.8 (7)	C9—O1—C1	121.2 (6)
O2—C1—C2—C3	179.1 (8)	C3—C8—C9—O1	1.3 (10)
O1—C1—C2—C3	−2.9 (11)	C4—C8—C9—C7	0.4 (11)
C1—C2—C3—C8	2.1 (11)	C3—C8—C9—C7	−179.7 (6)
C1—C2—C3—C10	−176.6 (7)	C6—C7—C9—O1	177.6 (6)
C8—C4—C5—C6	−3.6 (11)	N2—C7—C9—O1	−4.9 (9)
C8—C4—C5—N1	177.2 (7)	C6—C7—C9—C8	−1.5 (11)
C4—C5—C6—C7	2.5 (11)	N2—C7—C9—C8	176.0 (7)
N1—C5—C6—C7	−178.4 (6)	C2—C3—C10—Br	104.6 (7)
C4—C5—C6—C11	−175.8 (7)	C8—C3—C10—Br	−74.1 (7)
N1—C5—C6—C11	3.3 (11)	C4—C5—N1—O3	41.9 (11)
C5—C6—C7—C9	0.0 (10)	C6—C5—N1—O3	−137.3 (8)
C11—C6—C7—C9	178.4 (7)	C4—C5—N1—O4	−136.2 (8)
C5—C6—C7—N2	−177.3 (6)	C6—C5—N1—O4	44.6 (10)
C11—C6—C7—N2	1.0 (11)	C6—C7—N2—O5	−81.1 (10)
C5—C4—C8—C9	2.0 (11)	C9—C7—N2—O5	101.4 (9)
C5—C4—C8—C3	−177.9 (7)	C6—C7—N2—O6	101.1 (10)
C2—C3—C8—C4	178.7 (7)	C9—C7—N2—O6	−76.4 (10)
C10—C3—C8—C4	−2.6 (11)	C8—C9—O1—C1	−2.2 (10)
C2—C3—C8—C9	−1.2 (10)	C7—C9—O1—C1	178.7 (6)
C10—C3—C8—C9	177.5 (7)	O2—C1—O1—C9	−178.9 (7)
C4—C8—C9—O1	−178.6 (6)	C2—C1—O1—C9	2.9 (10)