3,6-Dibromo-7-ethyl­amino-4-methyl-2H-chromen-2-one

Zhang, T.; Xing, H.; Miao, C.; Sun, X.; Xi, H.

doi:10.1107/S160053681201077X

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 68| Part 4| April 2012| Page o1108

doi:10.1107/S160053681201077X

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3,6-Dibromo-7-ethylamino-4-methyl-2H-chromen-2-one

Ting Zhang,^a Huai-jie Xing,^a Chun-bao Miao,^a Xiao-qiang Sun ^a and Hai-tao Xi ^a ^*

^aKey Laboratory of Fine Chemical Engineering, Changzhou University, Changzhou 213164, Jiangsu, People's Republic of China
^*Correspondence e-mail: xht@cczu.edu.cn

(Received 2 March 2012; accepted 12 March 2012; online 17 March 2012)

In title compound, C₁₂H₁₁Br₂NO₂, the coumarin ring system is almost planar, the two rings being inclined to one another by 1.40 (15)°. There are two short intramolecular interactions (N—H⋯Br and C—H⋯Br) involving the Br atoms. In the crystal, molecules stack along the a-axis direction via π–π interactions; the centroid–centroid distances vary from 3.6484 (19) to 3.7942 (19) Å.

Related literature

For the synthesis of the title compound, see: Belluti et al. (2010 ). For geometrical details of a coumarin compound, see: Kruszynski et al. (2005 ).

Experimental

Crystal data

C₁₂H₁₁Br₂NO₂
M_r = 361.04
Triclinic, $[P \overline 1]$
a = 7.5795 (9) Å
b = 7.6839 (9) Å
c = 11.2610 (14) Å
α = 93.628 (2)°
β = 98.288 (3)°
γ = 102.626 (3)°
V = 630.24 (13) Å³
Z = 2
Mo Kα radiation
μ = 6.42 mm⁻¹
T = 293 K
0.20 × 0.18 × 0.15 mm

Data collection

Enraf–Nonius CAD-4 diffractometer
Absorption correction: ψ scan (North et al., 1968 ) T_min = 0.360, T_max = 0.446
3658 measured reflections
2314 independent reflections
1928 reflections with I > 2σ(I)
R_int = 0.023
3 standard reflections every 200 reflections intensity decay 1%

Refinement

R[F² > 2σ(F²)] = 0.031
wR(F²) = 0.097
S = 1.00
2314 reflections
160 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.51 e Å⁻³
Δρ_min = −0.42 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯Br1	0.86 (3)	2.67 (3)	3.055 (3)	109 (2)
C10—H10A⋯Br2	0.96	2.68	3.221 (4)	116

Data collection: CAD-4 Software (Enraf–Nonius, 1985 ); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995 ); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053681201077X/su2385sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681201077X/su2385Isup2.hkl

Supporting information file. DOI: 10.1107/S160053681201077X/su2385Isup3.cml

checkCIF report

Comment top

The title compound is used as an important intermediate to synthesis fluorescent tracers, for example, it has been recognized as an effective protein tracer (Belluti et al., 2010). Herein we report on the crystal structure of the title compound, which is illustrated in Fig. 1.

The coumarin ring system is almost planar with a dihedral angle involving rings (O2,C1-C5) and (C4-C9) of only 1.40 (2) °. This is normal for such coumarin compounds (Kruszynski et al., 2005). The bromine atoms are involved in short Br···H interactions (Table 1).

In the crystal, the molecules stack along the a axis direction (Fig. 2). There are a number of π–π interactions present: Cg1···Cg1ⁱ 3.7580 (19) Å; Cg2···Cg1ⁱ 3.6484(19 Å; Cg2···Cg2ⁱⁱ 3.7942 (19) Å [where Cg1 is the centroid of ring (O2,C1-C5); Cg2 is the centroid of ring (C4-C9); symmetry codes: (i) -x+1, -y+1, -z+1; (ii) -x+2, -y+1, -z+1].

Related literature top

For the synthesis of the title compound, see: Belluti et al. (2010). For geometrical details of a coumarin compound, see: Kruszynski et al. (2005).

Experimental top

The title compound was prepared by the method reported by (Belluti et al., 2010). To a suspension of 4-methyl-7-N,N-diethylamino coumarin (5 mmol, 1.61 g) and bromosuccinimide (6 mmol, 1.06 g) in carbon tetrachloride (50 ml), a catalytic amount of benzoyl peroxide was added. The reaction mixture was refluxed for 8 h, then the succinimide produced during the reaction was filtered off. The resulting mixture was washed with water, dried and the solvent was removed under reduced pressure. The pale yellow product obtained was recrystallized from ethanol, yielding colourless block-like crystals of the title compound on evaporating the solvent slowly at room temperature for about 5 days.

Structure description top

For the synthesis of the title compound, see: Belluti et al. (2010). For geometrical details of a coumarin compound, see: Kruszynski et al. (2005).

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1985); cell refinement: CAD-4 Software (Enraf–Nonius, 1985); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. The short Br···H interactions are shown as dashed lines.
	Fig. 2. A view along the a axis of the crystal packing of the title compound. The short Br···H interactions are shown as dashed lines.

3,6-Dibromo-7-ethylamino-4-methyl-2H-chromen-2-one top

Crystal data top

C₁₂H₁₁Br₂NO₂	Z = 2
M_r = 361.04	F(000) = 352
Triclinic, P1	D_x = 1.903 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.5795 (9) Å	Cell parameters from 1771 reflections
b = 7.6839 (9) Å	θ = 2.7–26.5°
c = 11.2610 (14) Å	µ = 6.42 mm⁻¹
α = 93.628 (2)°	T = 293 K
β = 98.288 (3)°	Block, colourless
γ = 102.626 (3)°	0.20 × 0.18 × 0.15 mm
V = 630.24 (13) Å³

Data collection top

Enraf–Nonius CAD-4 diffractometer	1928 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.023
Graphite monochromator	θ_max = 25.5°, θ_min = 1.8°
ω/2θ scans	h = −9→8
Absorption correction: ψ scan (North et al., 1968)	k = −8→9
T_min = 0.360, T_max = 0.446	l = −11→13
3658 measured reflections	3 standard reflections every 200 reflections
2314 independent reflections	intensity decay: 1%

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)] = 0.031	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.097	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	w = 1/[σ²(F_o²) + (0.0633P)² + 0.0665P] where P = (F_o² + 2F_c²)/3
2314 reflections	(Δ/σ)_max = 0.001
160 parameters	Δρ_max = 0.51 e Å⁻³
1 restraint	Δρ_min = −0.42 e Å⁻³

Crystal data top

C₁₂H₁₁Br₂NO₂	γ = 102.626 (3)°
M_r = 361.04	V = 630.24 (13) Å³
Triclinic, P1	Z = 2
a = 7.5795 (9) Å	Mo Kα radiation
b = 7.6839 (9) Å	µ = 6.42 mm⁻¹
c = 11.2610 (14) Å	T = 293 K
α = 93.628 (2)°	0.20 × 0.18 × 0.15 mm
β = 98.288 (3)°

Data collection top

Enraf–Nonius CAD-4 diffractometer	1928 reflections with I > 2σ(I)
Absorption correction: ψ scan (North et al., 1968)	R_int = 0.023
T_min = 0.360, T_max = 0.446	3 standard reflections every 200 reflections
3658 measured reflections	intensity decay: 1%
2314 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.031	1 restraint
wR(F²) = 0.097	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	Δρ_max = 0.51 e Å⁻³
2314 reflections	Δρ_min = −0.42 e Å⁻³
160 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
Br1	0.93608 (5)	0.72412 (5)	0.21480 (3)	0.05088 (16)
Br2	0.64459 (6)	0.54212 (6)	0.87739 (3)	0.05501 (16)
O1	0.5330 (4)	0.1746 (4)	0.7375 (2)	0.0561 (7)
O2	0.6172 (3)	0.2336 (3)	0.5627 (2)	0.0410 (6)
N1	0.7998 (4)	0.3167 (4)	0.1806 (3)	0.0403 (7)
C1	0.6005 (5)	0.2886 (5)	0.6787 (3)	0.0414 (8)
C2	0.6637 (5)	0.4800 (5)	0.7146 (3)	0.0388 (7)
C3	0.7310 (4)	0.6008 (4)	0.6420 (3)	0.0358 (7)
C4	0.7489 (4)	0.5355 (4)	0.5224 (3)	0.0335 (7)
C5	0.6917 (4)	0.3514 (4)	0.4864 (3)	0.0334 (7)
C6	0.7056 (4)	0.2766 (4)	0.3743 (3)	0.0352 (7)
H6	0.6655	0.1534	0.3547	0.042*
C7	0.7792 (4)	0.3845 (4)	0.2908 (3)	0.0331 (7)
C8	0.8355 (4)	0.5712 (4)	0.3261 (3)	0.0355 (7)
C9	0.8197 (4)	0.6442 (4)	0.4371 (3)	0.0358 (7)
H9	0.8565	0.7677	0.4561	0.043*
C10	0.7902 (5)	0.7994 (5)	0.6800 (3)	0.0480 (9)
H10A	0.7510	0.8247	0.7552	0.072*
H10B	0.7361	0.8632	0.6195	0.072*
H10C	0.9213	0.8366	0.6894	0.072*
C11	0.7252 (5)	0.1281 (5)	0.1345 (3)	0.0442 (8)
H11A	0.5925	0.1010	0.1252	0.053*
H11B	0.7695	0.0515	0.1913	0.053*
C12	0.7831 (6)	0.0925 (6)	0.0148 (4)	0.0589 (10)
H12A	0.9142	0.1137	0.0251	0.088*
H12B	0.7420	0.1709	−0.0405	0.088*
H12C	0.7300	−0.0298	−0.0166	0.088*
H1	0.848 (4)	0.380 (4)	0.128 (2)	0.036 (9)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0641 (3)	0.0348 (2)	0.0574 (3)	0.00657 (16)	0.02514 (19)	0.01385 (16)
Br2	0.0732 (3)	0.0580 (3)	0.0363 (2)	0.0195 (2)	0.01301 (18)	−0.00175 (17)
O1	0.0735 (18)	0.0491 (16)	0.0446 (15)	0.0014 (13)	0.0231 (13)	0.0100 (12)
O2	0.0551 (14)	0.0292 (11)	0.0361 (13)	0.0006 (10)	0.0133 (11)	0.0011 (9)
N1	0.0510 (17)	0.0316 (14)	0.0416 (16)	0.0079 (12)	0.0197 (14)	0.0049 (12)
C1	0.0445 (18)	0.0410 (19)	0.0381 (19)	0.0082 (15)	0.0064 (15)	0.0061 (15)
C2	0.0437 (18)	0.0423 (18)	0.0297 (17)	0.0106 (14)	0.0041 (14)	−0.0011 (14)
C3	0.0338 (16)	0.0327 (16)	0.0396 (18)	0.0092 (13)	0.0017 (14)	−0.0031 (13)
C4	0.0334 (15)	0.0308 (16)	0.0348 (17)	0.0063 (12)	0.0039 (13)	0.0004 (13)
C5	0.0351 (16)	0.0281 (15)	0.0368 (17)	0.0067 (12)	0.0048 (13)	0.0057 (13)
C6	0.0406 (17)	0.0258 (15)	0.0386 (18)	0.0070 (12)	0.0067 (14)	0.0013 (13)
C7	0.0320 (15)	0.0285 (15)	0.0394 (18)	0.0078 (12)	0.0072 (13)	0.0014 (13)
C8	0.0366 (16)	0.0303 (16)	0.0389 (18)	0.0045 (12)	0.0067 (14)	0.0089 (13)
C9	0.0365 (16)	0.0230 (14)	0.0457 (19)	0.0050 (12)	0.0028 (14)	0.0016 (13)
C10	0.056 (2)	0.0335 (18)	0.050 (2)	0.0035 (16)	0.0098 (17)	−0.0084 (16)
C11	0.051 (2)	0.0350 (18)	0.045 (2)	0.0058 (15)	0.0098 (16)	−0.0020 (15)
C12	0.077 (3)	0.052 (2)	0.047 (2)	0.013 (2)	0.015 (2)	−0.0055 (18)

Geometric parameters (Å, º) top

Br1—C8	1.899 (3)	C6—C7	1.390 (5)
Br2—C2	1.899 (3)	C6—H6	0.9300
O1—C1	1.200 (4)	C7—C8	1.418 (4)
O2—C5	1.375 (4)	C8—C9	1.369 (5)
O2—C1	1.379 (4)	C9—H9	0.9300
N1—C7	1.358 (4)	C10—H10A	0.9600
N1—C11	1.467 (4)	C10—H10B	0.9600
N1—H1	0.857 (5)	C10—H10C	0.9600
C1—C2	1.455 (5)	C11—C12	1.503 (5)
C2—C3	1.342 (5)	C11—H11A	0.9700
C3—C4	1.443 (5)	C11—H11B	0.9700
C3—C10	1.508 (4)	C12—H12A	0.9600
C4—C9	1.401 (5)	C12—H12B	0.9600
C4—C5	1.401 (4)	C12—H12C	0.9600
C5—C6	1.381 (5)

C5—O2—C1	122.3 (3)	C9—C8—C7	122.4 (3)
C7—N1—C11	122.7 (3)	C9—C8—Br1	119.2 (2)
C7—N1—H1	124 (2)	C7—C8—Br1	118.4 (2)
C11—N1—H1	113 (2)	C8—C9—C4	120.9 (3)
O1—C1—O2	116.8 (3)	C8—C9—H9	119.5
O1—C1—C2	127.6 (3)	C4—C9—H9	119.5
O2—C1—C2	115.7 (3)	C3—C10—H10A	109.5
C3—C2—C1	124.2 (3)	C3—C10—H10B	109.5
C3—C2—Br2	123.0 (3)	H10A—C10—H10B	109.5
C1—C2—Br2	112.8 (2)	C3—C10—H10C	109.5
C2—C3—C4	117.8 (3)	H10A—C10—H10C	109.5
C2—C3—C10	123.2 (3)	H10B—C10—H10C	109.5
C4—C3—C10	119.0 (3)	N1—C11—C12	109.7 (3)
C9—C4—C5	116.4 (3)	N1—C11—H11A	109.7
C9—C4—C3	124.5 (3)	C12—C11—H11A	109.7
C5—C4—C3	119.0 (3)	N1—C11—H11B	109.7
O2—C5—C6	115.9 (3)	C12—C11—H11B	109.7
O2—C5—C4	121.0 (3)	H11A—C11—H11B	108.2
C6—C5—C4	123.1 (3)	C11—C12—H12A	109.5
C5—C6—C7	120.3 (3)	C11—C12—H12B	109.5
C5—C6—H6	119.9	H12A—C12—H12B	109.5
C7—C6—H6	119.9	C11—C12—H12C	109.5
N1—C7—C6	122.4 (3)	H12A—C12—H12C	109.5
N1—C7—C8	120.7 (3)	H12B—C12—H12C	109.5
C6—C7—C8	116.9 (3)

C5—O2—C1—O1	179.8 (3)	C9—C4—C5—C6	1.1 (5)
C5—O2—C1—C2	1.1 (4)	C3—C4—C5—C6	−179.2 (3)
O1—C1—C2—C3	−177.1 (4)	O2—C5—C6—C7	−179.9 (3)
O2—C1—C2—C3	1.5 (5)	C4—C5—C6—C7	0.1 (5)
O1—C1—C2—Br2	3.8 (5)	C11—N1—C7—C6	8.0 (5)
O2—C1—C2—Br2	−177.6 (2)	C11—N1—C7—C8	−172.8 (3)
C1—C2—C3—C4	−2.8 (5)	C5—C6—C7—N1	178.4 (3)
Br2—C2—C3—C4	176.3 (2)	C5—C6—C7—C8	−0.8 (5)
C1—C2—C3—C10	178.0 (3)	N1—C7—C8—C9	−178.9 (3)
Br2—C2—C3—C10	−3.0 (5)	C6—C7—C8—C9	0.2 (5)
C2—C3—C4—C9	−178.8 (3)	N1—C7—C8—Br1	1.1 (4)
C10—C3—C4—C9	0.5 (5)	C6—C7—C8—Br1	−179.8 (2)
C2—C3—C4—C5	1.6 (5)	C7—C8—C9—C4	1.0 (5)
C10—C3—C4—C5	−179.2 (3)	Br1—C8—C9—C4	−179.0 (2)
C1—O2—C5—C6	177.8 (3)	C5—C4—C9—C8	−1.7 (5)
C1—O2—C5—C4	−2.2 (5)	C3—C4—C9—C8	178.7 (3)
C9—C4—C5—O2	−178.8 (3)	C7—N1—C11—C12	−175.8 (3)
C3—C4—C5—O2	0.8 (5)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···Br1	0.86 (3)	2.67 (3)	3.055 (3)	109 (2)
C10—H10A···Br2	0.96	2.68	3.221 (4)	116

Experimental details

Crystal data
Chemical formula	C₁₂H₁₁Br₂NO₂
M_r	361.04
Crystal system, space group	Triclinic, P1
Temperature (K)	293
a, b, c (Å)	7.5795 (9), 7.6839 (9), 11.2610 (14)
α, β, γ (°)	93.628 (2), 98.288 (3), 102.626 (3)
V (Å³)	630.24 (13)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	6.42
Crystal size (mm)	0.20 × 0.18 × 0.15

Data collection
Diffractometer	Enraf–Nonius CAD-4
Absorption correction	ψ scan (North et al., 1968)
T_min, T_max	0.360, 0.446
No. of measured, independent and observed [I > 2σ(I)] reflections	3658, 2314, 1928
R_int	0.023
(sin θ/λ)_max (Å⁻¹)	0.606

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.031, 0.097, 1.00
No. of reflections	2314
No. of parameters	160
No. of restraints	1
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.51, −0.42

Computer programs: CAD-4 Software (Enraf–Nonius, 1985), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···Br1	0.86 (3)	2.67 (3)	3.055 (3)	109 (2)
C10—H10A···Br2	0.96	2.68	3.221 (4)	116

Acknowledgements

The authors thank the Center of Testing and Analysis, Nanjing University, for the data collection.

References

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