N-(3-Bromo­phen­yl)-3,4,5-trimethoxy­benzamide

Saeed, A.; Hussain, S.; Ibrar, A.; Bolte, M.

doi:10.1107/S1600536809020509

organic compounds

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ISSN: 2056-9890

Volume 65| Part 7| July 2009| Page o1470

doi:10.1107/S1600536809020509

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N-(3-Bromophenyl)-3,4,5-trimethoxybenzamide

Aamer Saeed,^a ^* Shahid Hussain,^a Aliya Ibrar ^a and Michael Bolte ^b

^aDepartment of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan, and ^bInstitut für Anorganische Chemie, J. W. Goethe-Universität Frankfurt, Max-von-Laue-Str.7, 60438 Frankfurt/Main, Germany
^*Correspondence e-mail: aamersaeed@yahoo.com

(Received 21 May 2009; accepted 29 May 2009; online 6 June 2009)

In the title compound, C₁₆H₁₆BrNO₄, the dihedral between the planes of the aromatic rings is 7.74 (18)°. The amide group is tilted with respect to the bromo- and methoxy-substituted aromatic rings by 36.3 (8) and 35.2 (8)°, respectively. The meta-methoxy groups are essentially in-plane with the aromatic ring [dihedral angles CH₃—O—C—C = −4.6 (4) and −2.5 (4)°]. The para-methoxy group is markedly displaced from the ring plane [dihedral angle CH₃—O—C—C = −72.5 (4)°]. The crystal packing is stabilized by N—H⋯O hydrogen bonds linking the molecules into chains running along the b axis.

Related literature

For related structures and general background, see: Saeed et al. (2009 ). For conformations of aromatic methoxy groups, see: Vande Velde et al. (2006 ).

Experimental

Crystal data

C₁₆H₁₆BrNO₄
M_r = 366.21
Orthorhombic, P n a 2₁
a = 13.3085 (8) Å
b = 4.9953 (3) Å
c = 23.4061 (12) Å
V = 1556.04 (15) Å³
Z = 4
Mo Kα radiation
μ = 2.66 mm⁻¹
T = 173 K
0.37 × 0.34 × 0.19 mm

Data collection

Stoe IPDS II two-circle diffractometer
Absorption correction: multi-scan [MULABS (Spek, 2009 ; Blessing, 1995 )] T_min = 0.418, T_max = 0.600
11994 measured reflections
3028 independent reflections
2748 reflections with I > 2σ(I)
R_int = 0.056

Refinement

R[F² > 2σ(F²)] = 0.033
wR(F²) = 0.076
S = 0.99
3028 reflections
207 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.46 e Å⁻³
Δρ_min = −0.39 e Å⁻³
Absolute structure: Flack (1983 ), with 1405 Friedel pairs
Flack parameter: 0.001 (8)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O1ⁱ	0.85 (4)	2.06 (4)	2.821 (3)	149 (3)
Symmetry code: (i) x, y-1, z.

Data collection: X-AREA (Stoe & Cie, 2001 ); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809020509/zl2213sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809020509/zl2213Isup2.hkl

checkCIF report

Comment top

The background to this study has been described in an earlier paper on N-(2-chlorophenyl)-4-chlorobenzamide (Saeed et al., 2009). As part of our work on the structure of benzanilides and related compounds, we report here the structure of the title compound, Fig. 1.

In the title compound, C₁₆H₁₆BrNO₄, the dihedral angle between the aromatic rings is 7.74 (18)°. The amide moiety is tilted against the bromo and methoxy substituted aromatic rings by 36.3 (8)° and 35.2 (8)°, respectively. The meta methoxy groups are essentially in plane with the aromatic ring [dihedral angles CH₃—O—C—C = -4.6 (4)° and -2.5 (4)°], the methoxy group in para position is markedly displaced from the ring plane [dihedral angle CH₃—O—C—C = -72.5 (4)°]. This can be attributed to a combination of resonance effects, which lead for aromatic methoxy groups to being coplanar with an aromatic ring, and steric interactions, which prohibit a coplanar arrangement when more than two methoxy groups are present per benzene moiety (Vande Velde et al., 2006). The crystal packing is stabilized by N—H···O hydrogen bonds linking the molecules to chains running along the b axis (Fig. 2).

Related literature top

For related structures and general background, see: Saeed et al. (2009). For conformations of aromatic methoxy groups, see: Vande Velde et al. (2006).

Experimental top

3,4,5-Trimethoxybenzoyl chloride (5.4 mmol) in CHCl₃ was treated with 3-bromoaniline (21.6 mmol) under a nitrogen atmosphere at reflux for 3 h. Upon cooling, the reaction mixture was diluted with CHCl₃ and washed consecutively with aq 1 M HCl and saturated aq NaHCO₃. The organic layer was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. Crystallization of the residue in CHCl₃ afforded the title compound (81%) as colourless needles. Anal. calcd. for C₁₆H₁₆BrNO₄: C, 52.48; H, 4.40; N, 3.82%; found: C, 52.51; H, 4.36; N, 3.87

Computing details top

Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA (Stoe & Cie, 2001); data reduction: X-AREA (Stoe & Cie, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The title compound with the atom numbering scheme; displacement ellipsoids are at the 50% probability level; H atoms are drawn as small spheres of arbitrary radii.
	Fig. 2. Partial packing diagram of the title compound. Hydrogen bonds are drawn as dashed lines.

N-(3-Bromophenyl)-3,4,5-trimethoxybenzamide top

Crystal data top

C₁₆H₁₆BrNO₄	F(000) = 744
M_r = 366.21	D_x = 1.563 Mg m⁻³
Orthorhombic, Pna2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2n	Cell parameters from 11796 reflections
a = 13.3085 (8) Å	θ = 3.5–26.7°
b = 4.9953 (3) Å	µ = 2.66 mm⁻¹
c = 23.4061 (12) Å	T = 173 K
V = 1556.04 (15) Å³	Plate, colourless
Z = 4	0.37 × 0.34 × 0.19 mm

Data collection top

Stoe IPDS II two-circle diffractometer	3028 independent reflections
Radiation source: fine-focus sealed tube	2748 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.056
ω scans	θ_max = 26.3°, θ_min = 3.5°
Absorption correction: multi-scan [MULABS (Spek, 2009; Blessing, 1995)]	h = −16→16
T_min = 0.418, T_max = 0.600	k = −6→6
11994 measured reflections	l = −29→26

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F² > 2σ(F²)] = 0.033	w = 1/[σ²(F_o²) + (0.0493P)²] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.076	(Δ/σ)_max < 0.001
S = 0.99	Δρ_max = 0.46 e Å⁻³
3028 reflections	Δρ_min = −0.39 e Å⁻³
207 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
1 restraint	Extinction coefficient: 0.0168 (10)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), with 1405 Friedel pairs
Secondary atom site location: difference Fourier map	Absolute structure parameter: 0.001 (8)

Crystal data top

C₁₆H₁₆BrNO₄	V = 1556.04 (15) Å³
M_r = 366.21	Z = 4
Orthorhombic, Pna2₁	Mo Kα radiation
a = 13.3085 (8) Å	µ = 2.66 mm⁻¹
b = 4.9953 (3) Å	T = 173 K
c = 23.4061 (12) Å	0.37 × 0.34 × 0.19 mm

Data collection top

Stoe IPDS II two-circle diffractometer	3028 independent reflections
Absorption correction: multi-scan [MULABS (Spek, 2009; Blessing, 1995)]	2748 reflections with I > 2σ(I)
T_min = 0.418, T_max = 0.600	R_int = 0.056
11994 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.033	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.076	Δρ_max = 0.46 e Å⁻³
S = 0.99	Δρ_min = −0.39 e Å⁻³
3028 reflections	Absolute structure: Flack (1983), with 1405 Friedel pairs
207 parameters	Absolute structure parameter: 0.001 (8)
1 restraint

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	0.19897 (2)	0.79946 (7)	0.12371 (2)	0.04356 (13)
N1	0.52764 (18)	0.5080 (5)	0.23414 (11)	0.0203 (5)
H1	0.546 (3)	0.351 (8)	0.2441 (17)	0.023 (9)*
O1	0.51118 (18)	0.9515 (4)	0.25246 (10)	0.0285 (5)
O2	0.62891 (16)	0.9862 (4)	0.46087 (9)	0.0276 (4)
O3	0.78413 (15)	0.6364 (4)	0.46308 (10)	0.0259 (4)
O4	0.82971 (16)	0.3369 (4)	0.37342 (10)	0.0276 (5)
C1	0.5457 (2)	0.7303 (5)	0.26493 (13)	0.0204 (6)
C11	0.4666 (2)	0.4924 (5)	0.18432 (13)	0.0220 (6)
C12	0.3799 (2)	0.6447 (6)	0.17818 (13)	0.0246 (6)
H12	0.3613	0.7724	0.2063	0.030*
C13	0.3216 (2)	0.6057 (6)	0.13014 (16)	0.0279 (6)
C14	0.3467 (3)	0.4244 (7)	0.08727 (14)	0.0334 (7)
H14	0.3060	0.4043	0.0542	0.040*
C15	0.4334 (3)	0.2740 (7)	0.09471 (15)	0.0332 (7)
H15	0.4520	0.1466	0.0665	0.040*
C16	0.4931 (3)	0.3066 (6)	0.14241 (13)	0.0270 (6)
H16	0.5523	0.2022	0.1467	0.032*
C21	0.6099 (2)	0.6961 (5)	0.31655 (12)	0.0201 (5)
C22	0.5883 (2)	0.8619 (5)	0.36327 (13)	0.0220 (6)
H22	0.5343	0.9859	0.3614	0.026*
C23	0.6460 (2)	0.8435 (5)	0.41199 (12)	0.0206 (6)
C24	0.7280 (2)	0.6655 (5)	0.41433 (13)	0.0210 (6)
C25	0.7487 (2)	0.5016 (5)	0.36721 (13)	0.0201 (5)
C26	0.6890 (2)	0.5141 (5)	0.31853 (13)	0.0213 (6)
H26	0.7021	0.3997	0.2870	0.026*
C27	0.5500 (2)	1.1804 (6)	0.45934 (14)	0.0279 (6)
H27A	0.5610	1.3033	0.4273	0.042*
H27B	0.5495	1.2817	0.4952	0.042*
H27C	0.4853	1.0895	0.4545	0.042*
C28	0.8483 (3)	0.8582 (7)	0.47549 (15)	0.0337 (7)
H28A	0.9001	0.8727	0.4459	0.051*
H28B	0.8805	0.8308	0.5127	0.051*
H28C	0.8086	1.0232	0.4764	0.051*
C29	0.8502 (2)	0.1607 (6)	0.32691 (15)	0.0287 (7)
H29A	0.7910	0.0496	0.3194	0.043*
H29B	0.9074	0.0456	0.3366	0.043*
H29C	0.8664	0.2659	0.2928	0.043*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.02770 (15)	0.0536 (2)	0.0494 (2)	0.00300 (13)	−0.0092 (2)	0.0107 (3)
N1	0.0287 (12)	0.0138 (10)	0.0184 (12)	−0.0002 (9)	−0.0028 (10)	−0.0013 (9)
O1	0.0429 (12)	0.0152 (9)	0.0273 (11)	0.0026 (8)	−0.0104 (10)	−0.0011 (8)
O2	0.0303 (11)	0.0332 (10)	0.0192 (10)	0.0084 (8)	−0.0025 (9)	−0.0069 (9)
O3	0.0274 (10)	0.0289 (10)	0.0214 (11)	−0.0008 (8)	−0.0053 (8)	0.0023 (8)
O4	0.0232 (10)	0.0286 (11)	0.0311 (12)	0.0097 (8)	−0.0021 (9)	−0.0039 (9)
C1	0.0237 (13)	0.0175 (12)	0.0199 (14)	−0.0026 (9)	0.0012 (11)	0.0009 (10)
C11	0.0280 (14)	0.0206 (11)	0.0176 (14)	−0.0031 (11)	0.0002 (11)	0.0026 (11)
C12	0.0277 (15)	0.0248 (13)	0.0212 (14)	−0.0013 (11)	−0.0001 (12)	0.0019 (11)
C13	0.0250 (12)	0.0337 (13)	0.0251 (18)	−0.0052 (10)	0.0008 (13)	0.0053 (14)
C14	0.0352 (17)	0.0428 (17)	0.0223 (16)	−0.0146 (14)	−0.0052 (13)	0.0034 (14)
C15	0.0402 (19)	0.0357 (17)	0.0235 (17)	−0.0072 (14)	0.0011 (14)	−0.0058 (13)
C16	0.0326 (16)	0.0253 (14)	0.0232 (16)	−0.0008 (12)	0.0003 (12)	−0.0039 (11)
C21	0.0225 (14)	0.0169 (11)	0.0208 (14)	−0.0018 (10)	−0.0025 (10)	0.0014 (11)
C22	0.0244 (14)	0.0184 (12)	0.0232 (15)	0.0018 (10)	0.0007 (12)	−0.0005 (10)
C23	0.0242 (14)	0.0197 (13)	0.0178 (14)	−0.0015 (10)	0.0040 (11)	−0.0035 (11)
C24	0.0215 (13)	0.0229 (13)	0.0186 (14)	−0.0018 (10)	−0.0016 (11)	0.0009 (11)
C25	0.0181 (12)	0.0185 (13)	0.0238 (15)	−0.0001 (10)	0.0005 (11)	0.0021 (10)
C26	0.0243 (14)	0.0191 (12)	0.0205 (14)	−0.0010 (10)	0.0029 (11)	−0.0019 (10)
C27	0.0324 (16)	0.0244 (14)	0.0269 (16)	0.0064 (12)	0.0015 (13)	−0.0055 (12)
C28	0.0318 (17)	0.0352 (17)	0.0341 (19)	−0.0032 (14)	−0.0116 (14)	−0.0036 (14)
C29	0.0296 (16)	0.0257 (15)	0.0308 (17)	0.0070 (12)	0.0062 (13)	−0.0021 (13)

Geometric parameters (Å, º) top

Br1—C13	1.903 (3)	C15—H15	0.9500
N1—C1	1.346 (4)	C16—H16	0.9500
N1—C11	1.423 (4)	C21—C26	1.392 (4)
N1—H1	0.85 (4)	C21—C22	1.401 (4)
O1—C1	1.232 (3)	C22—C23	1.378 (4)
O2—C23	1.367 (3)	C22—H22	0.9500
O2—C27	1.431 (3)	C23—C24	1.409 (4)
O3—C24	1.371 (4)	C24—C25	1.401 (4)
O3—C28	1.429 (4)	C25—C26	1.391 (4)
O4—C25	1.363 (3)	C26—H26	0.9500
O4—C29	1.426 (4)	C27—H27A	0.9800
C1—C21	1.490 (4)	C27—H27B	0.9800
C11—C12	1.389 (4)	C27—H27C	0.9800
C11—C16	1.396 (4)	C28—H28A	0.9800
C12—C13	1.380 (5)	C28—H28B	0.9800
C12—H12	0.9500	C28—H28C	0.9800
C13—C14	1.393 (5)	C29—H29A	0.9800
C14—C15	1.388 (5)	C29—H29B	0.9800
C14—H14	0.9500	C29—H29C	0.9800
C15—C16	1.379 (4)

C1—N1—C11	125.9 (2)	C21—C22—H22	120.3
C1—N1—H1	124 (2)	O2—C23—C22	124.4 (3)
C11—N1—H1	110 (2)	O2—C23—C24	115.2 (2)
C23—O2—C27	117.1 (2)	C22—C23—C24	120.4 (3)
C24—O3—C28	114.4 (2)	O3—C24—C25	119.1 (3)
C25—O4—C29	116.3 (2)	O3—C24—C23	121.4 (2)
O1—C1—N1	123.2 (3)	C25—C24—C23	119.4 (3)
O1—C1—C21	120.6 (2)	O4—C25—C26	124.5 (3)
N1—C1—C21	116.2 (2)	O4—C25—C24	115.1 (3)
C12—C11—C16	120.1 (3)	C26—C25—C24	120.4 (2)
C12—C11—N1	121.9 (3)	C25—C26—C21	119.3 (3)
C16—C11—N1	117.9 (3)	C25—C26—H26	120.4
C13—C12—C11	118.3 (3)	C21—C26—H26	120.4
C13—C12—H12	120.8	O2—C27—H27A	109.5
C11—C12—H12	120.8	O2—C27—H27B	109.5
C12—C13—C14	122.9 (3)	H27A—C27—H27B	109.5
C12—C13—Br1	118.4 (3)	O2—C27—H27C	109.5
C14—C13—Br1	118.7 (2)	H27A—C27—H27C	109.5
C15—C14—C13	117.5 (3)	H27B—C27—H27C	109.5
C15—C14—H14	121.3	O3—C28—H28A	109.5
C13—C14—H14	121.3	O3—C28—H28B	109.5
C16—C15—C14	121.1 (3)	H28A—C28—H28B	109.5
C16—C15—H15	119.5	O3—C28—H28C	109.5
C14—C15—H15	119.5	H28A—C28—H28C	109.5
C15—C16—C11	120.1 (3)	H28B—C28—H28C	109.5
C15—C16—H16	119.9	O4—C29—H29A	109.5
C11—C16—H16	119.9	O4—C29—H29B	109.5
C26—C21—C22	121.0 (3)	H29A—C29—H29B	109.5
C26—C21—C1	122.4 (2)	O4—C29—H29C	109.5
C22—C21—C1	116.6 (2)	H29A—C29—H29C	109.5
C23—C22—C21	119.5 (3)	H29B—C29—H29C	109.5
C23—C22—H22	120.3

C11—N1—C1—O1	−0.9 (5)	C27—O2—C23—C22	−4.6 (4)
C11—N1—C1—C21	178.3 (3)	C27—O2—C23—C24	176.5 (2)
C1—N1—C11—C12	−35.8 (4)	C21—C22—C23—O2	−176.9 (3)
C1—N1—C11—C16	147.8 (3)	C21—C22—C23—C24	1.9 (4)
C16—C11—C12—C13	0.3 (4)	C28—O3—C24—C25	111.7 (3)
N1—C11—C12—C13	−176.0 (3)	C28—O3—C24—C23	−72.5 (4)
C11—C12—C13—C14	−1.2 (4)	O2—C23—C24—O3	1.4 (4)
C11—C12—C13—Br1	176.5 (2)	C22—C23—C24—O3	−177.5 (3)
C12—C13—C14—C15	1.5 (5)	O2—C23—C24—C25	177.1 (2)
Br1—C13—C14—C15	−176.2 (2)	C22—C23—C24—C25	−1.8 (4)
C13—C14—C15—C16	−1.0 (5)	C29—O4—C25—C26	−2.5 (4)
C14—C15—C16—C11	0.2 (5)	C29—O4—C25—C24	177.7 (3)
C12—C11—C16—C15	0.2 (4)	O3—C24—C25—O4	−4.4 (4)
N1—C11—C16—C15	176.6 (3)	C23—C24—C25—O4	179.8 (2)
O1—C1—C21—C26	−146.1 (3)	O3—C24—C25—C26	175.8 (3)
N1—C1—C21—C26	34.6 (4)	C23—C24—C25—C26	0.0 (4)
O1—C1—C21—C22	32.5 (4)	O4—C25—C26—C21	−178.2 (2)
N1—C1—C21—C22	−146.8 (3)	C24—C25—C26—C21	1.6 (4)
C26—C21—C22—C23	−0.3 (4)	C22—C21—C26—C25	−1.5 (4)
C1—C21—C22—C23	−178.9 (2)	C1—C21—C26—C25	177.1 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1ⁱ	0.85 (4)	2.06 (4)	2.821 (3)	149 (3)

Symmetry code: (i) x, y−1, z.

Experimental details

Crystal data
Chemical formula	C₁₆H₁₆BrNO₄
M_r	366.21
Crystal system, space group	Orthorhombic, Pna2₁
Temperature (K)	173
a, b, c (Å)	13.3085 (8), 4.9953 (3), 23.4061 (12)
V (Å³)	1556.04 (15)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	2.66
Crystal size (mm)	0.37 × 0.34 × 0.19

Data collection
Diffractometer	Stoe IPDS II two-circle diffractometer
Absorption correction	Multi-scan [MULABS (Spek, 2009; Blessing, 1995)]
T_min, T_max	0.418, 0.600
No. of measured, independent and observed [I > 2σ(I)] reflections	11994, 3028, 2748
R_int	0.056
(sin θ/λ)_max (Å⁻¹)	0.624

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.076, 0.99
No. of reflections	3028
No. of parameters	207
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)	0.46, −0.39
Absolute structure	Flack (1983), with 1405 Friedel pairs
Absolute structure parameter	0.001 (8)

Computer programs: X-AREA (Stoe & Cie, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1ⁱ	0.85 (4)	2.06 (4)	2.821 (3)	149 (3)

Symmetry code: (i) x, y−1, z.

Acknowledgements

AI gratefully acknowledges a research scholarship from the HEC, Islamabad, Pakistan, under the HEC Indigenous PhD Scholarship 5000 Scheme.

References

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