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ISSN: 2056-9890

A monoclinic polymorph of N-(3-chloro­phen­yl)benzamide

aDepartment of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan, bChemistry Division, Directorate of Science, PINSTECH, Nilore, Islamabad, Pakistan, and cDepartment of Chemistry, University of Otago, PO Box 56, Dunedin, New Zealand
*Correspondence e-mail: aamersaeed@yahoo.com

(Received 3 October 2010; accepted 8 October 2010; online 13 October 2010)

The title compound, C13H10ClNO, (I), is a polymorph of the structure, (II), first reported by Gowda et al. [Acta Cryst. (2008), E64, o462]. In the original report, the compound crystallized in the ortho­rhom­bic space group Pbca (Z = 8), whereas the structure reported here is monoclinic P21/c (Z = 4). The principal difference between the two forms lies in the relative orientations of the phenyl and benzene rings [dihedral angle = 8.90 (13)° for (I) and 61.0 (1)° for (II)]. The inclination of the amide –CONH– units to the benzoyl ring is more similar [15.8 (7)° for (I) and 18.2 (2)° for (II)]. In both forms, the N—H bonds are anti to the 3-chloro substituents of the aniline rings. In the crystal, inter­molecular N—H⋯O hydrogen bonds form C(4) chains along c. These chains are bolstered by weak C—H⋯O inter­actions that generate R21(6) and R21(7) ring motifs.

Related literature

For background to the biological activity of N-substituted benzamides and their use in synthesis, see: Saeed et al. (2010[Saeed, A., Khera, R. A. & Simpson, J. (2010). Acta Cryst. E66, o911-o912.]). For the ortho­rhom­bic polymorph of (I)[link], see: Gowda, Tokarčík et al. (2008[Gowda, B. T., Tokarčík, M., Kožíšek, J., Sowmya, B. P. & Fuess, H. (2008). Acta Cryst. E64, o462.]). For the structures of related chloro­phenyl­benzamides, see: Gowda et al. (2007a[Gowda, B. T., Sowmya, B. P., Kožíšek, J., Tokarčík, M. & Fuess, H. (2007a). Acta Cryst. E63, o2906.],b[Gowda, B. T., Sowmya, B. P., Tokarčík, M., Kožíšek, J. & Fuess, H. (2007b). Acta Cryst. E63, o3326.],c[Gowda, B. T., Sowmya, B. P., Tokarčík, M., Kožíšek, J. & Fuess, H. (2007c). Acta Cryst. E63, o3365.]); Gowda, Foro et al. (2008[Gowda, B. T., Foro, S., Sowmya, B. P. & Fuess, H. (2008). Acta Cryst. E64, o1243.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C13H10ClNO

  • Mr = 231.67

  • Monoclinic, P 21 /c

  • a = 12.5598 (17) Å

  • b = 10.2782 (14) Å

  • c = 9.0788 (13) Å

  • β = 109.421 (5)°

  • V = 1105.3 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.32 mm−1

  • T = 90 K

  • 0.57 × 0.22 × 0.03 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2006[Bruker (2006). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.743, Tmax = 1.000

  • 6385 measured reflections

  • 2045 independent reflections

  • 1475 reflections with I > 2σ(I)

  • Rint = 0.047

Refinement
  • R[F2 > 2σ(F2)] = 0.041

  • wR(F2) = 0.104

  • S = 1.04

  • 2045 reflections

  • 148 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.26 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O1i 0.88 (2) 1.99 (2) 2.841 (2) 163 (2)
C7—H7⋯O1i 0.95 2.45 3.228 (3) 139
C13—H13⋯O1i 0.95 2.71 3.301 (3) 121
Symmetry code: (i) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker 2006[Bruker (2006). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2 and SAINT (Bruker 2006[Bruker (2006). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and TITAN2000 (Hunter & Simpson, 1999[Hunter, K. A. & Simpson, J. (1999). TITAN2000. University of Otago, New Zealand.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: SHELXL97, enCIFer (Allen et al., 2004[Allen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst. 37, 335-338.]), PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

N-substituted benzamides have numerous pharmaceutical and synthetic applications (Saeed et al., 2010). The title compound, (I), is a monoclinic polymorph of the structure of this benzamide derivative which crystallizes in the space group P21/c. An alternative structure, (II), in the orthorhombic space group Pbca was reported previously by Gowda, Tokarčík et al., (2008).

Bond distances in the molecule are normal (Allen et al., 1987) and very similar to those in the orthorhombic polymorph and in closely related chlorophenylbenzamide derivatives (Gowda et al., 2007a,b,c); Gowda, Foro et al., 2008). However, the two polymorphs differ markedly in the relative orientations of the C2···C6 phenyl and C8···C13 benzene rings [dihedral angles 8.90 (13) for (I) and 61.0 (1) for (II)]. The inclination of the amide –C1O1N1H1- units to the C2···C6 ring is more similar [15.8 (7) for (I) and 18.2 (2) for (II). The N1–H1 bonds in both forms are anti to the Cl1 substituents of the C8···C13 aniline rings. This behaviour parallels that observed with N-(2-chlorophenyl)benzamide (Gowda et al., 2007a) and N-(3,4-dichlorophenyl)benzamide (Gowda et al., 2007c), whereas the a syn conformation is favoured in N-(2,3-dichlorophenyl)benzamide (Gowda et al., 2007b)

In the crystal structure, Fig. 2, intermolecular N1–H1···O1 hydrogen bonds form C4 chains along the c axis (Bernstein et al. 1995). These chains are further stabilized by weak C7–H5···O1 and C13–H13···O1 interactions that generate an R21(7) motif involving the an ortho-H atom from the phenyl ring and an R21(6) motif incorporating an ortho-H atom from the chlorobenzene ring respectively.

Related literature top

For background to the biological activity of N-substituted benzamides and their use in synthesis, see: Saeed et al. (2010). For the orthorhombic polymorph of (I), see: Gowda, Tokarčík et al. (2008). For the structures of related chlorophenylbenzamides, see: Gowda et al. (2007a,b,c); Gowda, Foro et al. (2008). For hydrogen-bond motifs, see: Bernstein et al. (1995). For bond-length data, see: Allen et al. (1987).

Experimental top

Freshly distilled benzoyl chloride (1 mmol) in CHCl3 was treated with 3-chloroaniline (3.5 mmol) under a nitrogen atmosphere at reflux for 2.5 h. Upon cooling, the reaction mixture was diluted with CHCl3 and washed consecutively with 1 M aq HCl and saturated aq NaHCO3. The organic layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure. Crystallization of the residue from ethanol afforded the title compound (83%) as colourless crystals: Anal. calcd. for C13H10ClNO: C, 67.39; H, 4.35; N, 6.05; found: C, 67.21; H, 4.42; N, 6.10%.

Refinement top

The H atom bound to N1 was located in a difference map and refined isotropically. All other H-atoms were positioned geometrically and refined using a riding model with d(C—H) = 0.95 Å, Uiso = 1.2Ueq (C).

Structure description top

N-substituted benzamides have numerous pharmaceutical and synthetic applications (Saeed et al., 2010). The title compound, (I), is a monoclinic polymorph of the structure of this benzamide derivative which crystallizes in the space group P21/c. An alternative structure, (II), in the orthorhombic space group Pbca was reported previously by Gowda, Tokarčík et al., (2008).

Bond distances in the molecule are normal (Allen et al., 1987) and very similar to those in the orthorhombic polymorph and in closely related chlorophenylbenzamide derivatives (Gowda et al., 2007a,b,c); Gowda, Foro et al., 2008). However, the two polymorphs differ markedly in the relative orientations of the C2···C6 phenyl and C8···C13 benzene rings [dihedral angles 8.90 (13) for (I) and 61.0 (1) for (II)]. The inclination of the amide –C1O1N1H1- units to the C2···C6 ring is more similar [15.8 (7) for (I) and 18.2 (2) for (II). The N1–H1 bonds in both forms are anti to the Cl1 substituents of the C8···C13 aniline rings. This behaviour parallels that observed with N-(2-chlorophenyl)benzamide (Gowda et al., 2007a) and N-(3,4-dichlorophenyl)benzamide (Gowda et al., 2007c), whereas the a syn conformation is favoured in N-(2,3-dichlorophenyl)benzamide (Gowda et al., 2007b)

In the crystal structure, Fig. 2, intermolecular N1–H1···O1 hydrogen bonds form C4 chains along the c axis (Bernstein et al. 1995). These chains are further stabilized by weak C7–H5···O1 and C13–H13···O1 interactions that generate an R21(7) motif involving the an ortho-H atom from the phenyl ring and an R21(6) motif incorporating an ortho-H atom from the chlorobenzene ring respectively.

For background to the biological activity of N-substituted benzamides and their use in synthesis, see: Saeed et al. (2010). For the orthorhombic polymorph of (I), see: Gowda, Tokarčík et al. (2008). For the structures of related chlorophenylbenzamides, see: Gowda et al. (2007a,b,c); Gowda, Foro et al. (2008). For hydrogen-bond motifs, see: Bernstein et al. (1995). For bond-length data, see: Allen et al. (1987).

Computing details top

Data collection: APEX2 (Bruker 2006); cell refinement: APEX2 and SAINT (Bruker 2006); data reduction: SAINT (Bruker 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and TITAN2000 (Hunter & Simpson, 1999); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), enCIFer (Allen et al., 2004), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The structure of (I) with displacement ellipsoids for the non-hydrogen atoms drawn at the 50% probability level.
[Figure 2] Fig. 2. Crystal packing for (I) viewed along the b axis with hydrogen bonds drawn as dashed lines.
N-(3-chlorophenyl)benzamide top
Crystal data top
C13H10ClNOF(000) = 480
Mr = 231.67Dx = 1.392 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1106 reflections
a = 12.5598 (17) Åθ = 2.6–25.3°
b = 10.2782 (14) ŵ = 0.32 mm1
c = 9.0788 (13) ÅT = 90 K
β = 109.421 (5)°Rectangular plate, colourless
V = 1105.3 (3) Å30.57 × 0.22 × 0.03 mm
Z = 4
Data collection top
Bruker APEXII CCD
diffractometer
2045 independent reflections
Radiation source: fine-focus sealed tube1475 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.047
ω scansθmax = 25.5°, θmin = 3.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2006)
h = 1515
Tmin = 0.743, Tmax = 1.000k = 1212
6385 measured reflectionsl = 910
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.104H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.0439P)2 + 0.2503P]
where P = (Fo2 + 2Fc2)/3
2045 reflections(Δ/σ)max = 0.001
148 parametersΔρmax = 0.29 e Å3
0 restraintsΔρmin = 0.26 e Å3
Crystal data top
C13H10ClNOV = 1105.3 (3) Å3
Mr = 231.67Z = 4
Monoclinic, P21/cMo Kα radiation
a = 12.5598 (17) ŵ = 0.32 mm1
b = 10.2782 (14) ÅT = 90 K
c = 9.0788 (13) Å0.57 × 0.22 × 0.03 mm
β = 109.421 (5)°
Data collection top
Bruker APEXII CCD
diffractometer
2045 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2006)
1475 reflections with I > 2σ(I)
Tmin = 0.743, Tmax = 1.000Rint = 0.047
6385 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0410 restraints
wR(F2) = 0.104H atoms treated by a mixture of independent and constrained refinement
S = 1.04Δρmax = 0.29 e Å3
2045 reflectionsΔρmin = 0.26 e Å3
148 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
xyzUiso*/Ueq
N10.58959 (16)0.22008 (18)0.5519 (2)0.0208 (4)
H10.5656 (19)0.202 (2)0.451 (3)0.025*
C10.52721 (18)0.3046 (2)0.6039 (3)0.0187 (5)
O10.55935 (12)0.34896 (15)0.73758 (17)0.0223 (4)
C20.41446 (18)0.3409 (2)0.4894 (2)0.0180 (5)
C30.35873 (19)0.4469 (2)0.5262 (3)0.0217 (5)
H30.39240.49290.62110.026*
C40.25445 (19)0.4852 (2)0.4248 (3)0.0233 (5)
H40.21670.55720.45090.028*
C50.20480 (19)0.4194 (2)0.2856 (3)0.0251 (6)
H50.13410.44730.21510.030*
C70.36288 (18)0.2734 (2)0.3510 (3)0.0215 (5)
H70.39920.19980.32570.026*
C80.69653 (18)0.1670 (2)0.6371 (2)0.0188 (5)
C90.77139 (19)0.2275 (2)0.7677 (3)0.0204 (5)
H90.75160.30620.80710.025*
C100.87564 (19)0.1698 (2)0.8386 (3)0.0220 (5)
C110.9070 (2)0.0546 (2)0.7871 (3)0.0242 (5)
H110.97860.01650.83930.029*
C120.8316 (2)0.0039 (2)0.6576 (3)0.0256 (6)
H120.85160.08320.62000.031*
C130.72744 (19)0.0511 (2)0.5819 (3)0.0232 (5)
H130.67670.01010.49210.028*
Cl10.96981 (5)0.24773 (6)1.00047 (7)0.0317 (2)
C60.25863 (19)0.3132 (2)0.2499 (3)0.0259 (6)
H60.22410.26690.15540.031*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0224 (10)0.0271 (10)0.0112 (10)0.0031 (8)0.0033 (9)0.0010 (9)
C10.0210 (12)0.0203 (11)0.0161 (12)0.0029 (9)0.0079 (10)0.0025 (10)
O10.0246 (9)0.0287 (8)0.0135 (9)0.0002 (7)0.0063 (7)0.0022 (7)
C20.0179 (11)0.0220 (11)0.0152 (12)0.0020 (9)0.0067 (9)0.0035 (9)
C30.0295 (13)0.0221 (11)0.0153 (12)0.0033 (10)0.0100 (10)0.0011 (10)
C40.0261 (13)0.0247 (12)0.0228 (13)0.0053 (10)0.0131 (11)0.0038 (10)
C50.0184 (12)0.0322 (13)0.0237 (14)0.0022 (10)0.0056 (10)0.0041 (11)
C70.0193 (12)0.0248 (12)0.0199 (12)0.0003 (9)0.0057 (10)0.0008 (10)
C80.0195 (12)0.0229 (12)0.0134 (12)0.0015 (9)0.0048 (10)0.0052 (9)
C90.0252 (13)0.0213 (12)0.0161 (12)0.0014 (9)0.0085 (10)0.0027 (10)
C100.0226 (12)0.0285 (12)0.0138 (12)0.0027 (10)0.0043 (10)0.0043 (10)
C110.0217 (12)0.0309 (13)0.0207 (13)0.0052 (10)0.0081 (10)0.0081 (11)
C120.0329 (14)0.0221 (12)0.0244 (14)0.0059 (10)0.0129 (12)0.0040 (10)
C130.0272 (13)0.0240 (12)0.0179 (12)0.0010 (10)0.0068 (10)0.0019 (10)
Cl10.0246 (3)0.0376 (4)0.0256 (4)0.0006 (3)0.0013 (3)0.0033 (3)
C60.0227 (13)0.0319 (13)0.0204 (13)0.0038 (11)0.0034 (10)0.0022 (11)
Geometric parameters (Å, º) top
N1—C11.356 (3)C7—H70.9500
N1—C81.418 (3)C8—C91.392 (3)
N1—H10.88 (2)C8—C131.396 (3)
C1—O11.232 (2)C9—C101.386 (3)
C1—C21.499 (3)C9—H90.9500
C2—C71.392 (3)C10—C111.378 (3)
C2—C31.394 (3)C10—Cl11.745 (2)
C3—C41.384 (3)C11—C121.378 (3)
C3—H30.9500C11—H110.9500
C4—C51.386 (3)C12—C131.381 (3)
C4—H40.9500C12—H120.9500
C5—C61.378 (3)C13—H130.9500
C5—H50.9500C6—H60.9500
C7—C61.387 (3)
C1—N1—C8127.52 (19)C9—C8—C13119.9 (2)
C1—N1—H1117.3 (16)C9—C8—N1122.8 (2)
C8—N1—H1114.8 (16)C13—C8—N1117.3 (2)
O1—C1—N1122.8 (2)C10—C9—C8118.1 (2)
O1—C1—C2121.1 (2)C10—C9—H9121.0
N1—C1—C2116.09 (19)C8—C9—H9121.0
C7—C2—C3119.1 (2)C11—C10—C9122.9 (2)
C7—C2—C1123.4 (2)C11—C10—Cl1119.38 (18)
C3—C2—C1117.5 (2)C9—C10—Cl1117.77 (18)
C4—C3—C2120.1 (2)C12—C11—C10118.1 (2)
C4—C3—H3119.9C12—C11—H11120.9
C2—C3—H3119.9C10—C11—H11120.9
C3—C4—C5120.5 (2)C11—C12—C13121.0 (2)
C3—C4—H4119.8C11—C12—H12119.5
C5—C4—H4119.8C13—C12—H12119.5
C6—C5—C4119.6 (2)C12—C13—C8120.1 (2)
C6—C5—H5120.2C12—C13—H13120.0
C4—C5—H5120.2C8—C13—H13120.0
C6—C7—C2120.2 (2)C5—C6—C7120.4 (2)
C6—C7—H7119.9C5—C6—H6119.8
C2—C7—H7119.9C7—C6—H6119.8
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O1i0.88 (2)1.99 (2)2.841 (2)163 (2)
C7—H7···O1i0.952.453.228 (3)139
C13—H13···O1i0.952.713.301 (3)121
Symmetry code: (i) x, y+1/2, z1/2.

Experimental details

Crystal data
Chemical formulaC13H10ClNO
Mr231.67
Crystal system, space groupMonoclinic, P21/c
Temperature (K)90
a, b, c (Å)12.5598 (17), 10.2782 (14), 9.0788 (13)
β (°) 109.421 (5)
V3)1105.3 (3)
Z4
Radiation typeMo Kα
µ (mm1)0.32
Crystal size (mm)0.57 × 0.22 × 0.03
Data collection
DiffractometerBruker APEXII CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2006)
Tmin, Tmax0.743, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
6385, 2045, 1475
Rint0.047
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.041, 0.104, 1.04
No. of reflections2045
No. of parameters148
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.29, 0.26

Computer programs: APEX2 (Bruker 2006), APEX2 and SAINT (Bruker 2006), SAINT (Bruker 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008) and TITAN2000 (Hunter & Simpson, 1999), SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2008), SHELXL97 (Sheldrick, 2008), enCIFer (Allen et al., 2004), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O1i0.88 (2)1.99 (2)2.841 (2)163 (2)
C7—H7···O1i0.952.453.228 (3)138.9
C13—H13···O1i0.952.713.301 (3)120.9
Symmetry code: (i) x, y+1/2, z1/2.
 

Acknowledgements

We thank the University of Otago for purchase of the diffractometer.

References

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