organic compounds
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
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 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). 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
Crystal data
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Refinement
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Data collection: APEX2 (Bruker 2006); cell APEX2 and SAINT (Bruker 2006); data reduction: SAINT; 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, enCIFer (Allen et al., 2004), PLATON (Spek, 2009) and publCIF (Westrip, 2010).
Supporting information
https://doi.org/10.1107/S1600536810040262/lh5145sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810040262/lh5145Isup2.hkl
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%.
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).
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
P21/c. An alternative structure, (II), in the orthorhombic 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
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).
Data collection: APEX2 (Bruker 2006); cell
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).C13H10ClNO | F(000) = 480 |
Mr = 231.67 | Dx = 1.392 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 1106 reflections |
a = 12.5598 (17) Å | θ = 2.6–25.3° |
b = 10.2782 (14) Å | µ = 0.32 mm−1 |
c = 9.0788 (13) Å | T = 90 K |
β = 109.421 (5)° | Rectangular plate, colourless |
V = 1105.3 (3) Å3 | 0.57 × 0.22 × 0.03 mm |
Z = 4 |
Bruker APEXII CCD diffractometer | 2045 independent reflections |
Radiation source: fine-focus sealed tube | 1475 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.047 |
ω scans | θmax = 25.5°, θmin = 3.1° |
Absorption correction: multi-scan (SADABS; Bruker, 2006) | h = −15→15 |
Tmin = 0.743, Tmax = 1.000 | k = −12→12 |
6385 measured reflections | l = −9→10 |
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)] = 0.041 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.104 | H 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 parameters | Δρmax = 0.29 e Å−3 |
0 restraints | Δρmin = −0.26 e Å−3 |
C13H10ClNO | V = 1105.3 (3) Å3 |
Mr = 231.67 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 12.5598 (17) Å | µ = 0.32 mm−1 |
b = 10.2782 (14) Å | T = 90 K |
c = 9.0788 (13) Å | 0.57 × 0.22 × 0.03 mm |
β = 109.421 (5)° |
Bruker APEXII CCD diffractometer | 2045 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2006) | 1475 reflections with I > 2σ(I) |
Tmin = 0.743, Tmax = 1.000 | Rint = 0.047 |
6385 measured reflections |
R[F2 > 2σ(F2)] = 0.041 | 0 restraints |
wR(F2) = 0.104 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.04 | Δρmax = 0.29 e Å−3 |
2045 reflections | Δρmin = −0.26 e Å−3 |
148 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 | ||
N1 | 0.58959 (16) | 0.22008 (18) | 0.5519 (2) | 0.0208 (4) | |
H1 | 0.5656 (19) | 0.202 (2) | 0.451 (3) | 0.025* | |
C1 | 0.52721 (18) | 0.3046 (2) | 0.6039 (3) | 0.0187 (5) | |
O1 | 0.55935 (12) | 0.34896 (15) | 0.73758 (17) | 0.0223 (4) | |
C2 | 0.41446 (18) | 0.3409 (2) | 0.4894 (2) | 0.0180 (5) | |
C3 | 0.35873 (19) | 0.4469 (2) | 0.5262 (3) | 0.0217 (5) | |
H3 | 0.3924 | 0.4929 | 0.6211 | 0.026* | |
C4 | 0.25445 (19) | 0.4852 (2) | 0.4248 (3) | 0.0233 (5) | |
H4 | 0.2167 | 0.5572 | 0.4509 | 0.028* | |
C5 | 0.20480 (19) | 0.4194 (2) | 0.2856 (3) | 0.0251 (6) | |
H5 | 0.1341 | 0.4473 | 0.2151 | 0.030* | |
C7 | 0.36288 (18) | 0.2734 (2) | 0.3510 (3) | 0.0215 (5) | |
H7 | 0.3992 | 0.1998 | 0.3257 | 0.026* | |
C8 | 0.69653 (18) | 0.1670 (2) | 0.6371 (2) | 0.0188 (5) | |
C9 | 0.77139 (19) | 0.2275 (2) | 0.7677 (3) | 0.0204 (5) | |
H9 | 0.7516 | 0.3062 | 0.8071 | 0.025* | |
C10 | 0.87564 (19) | 0.1698 (2) | 0.8386 (3) | 0.0220 (5) | |
C11 | 0.9070 (2) | 0.0546 (2) | 0.7871 (3) | 0.0242 (5) | |
H11 | 0.9786 | 0.0165 | 0.8393 | 0.029* | |
C12 | 0.8316 (2) | −0.0039 (2) | 0.6576 (3) | 0.0256 (6) | |
H12 | 0.8516 | −0.0832 | 0.6200 | 0.031* | |
C13 | 0.72744 (19) | 0.0511 (2) | 0.5819 (3) | 0.0232 (5) | |
H13 | 0.6767 | 0.0101 | 0.4921 | 0.028* | |
Cl1 | 0.96981 (5) | 0.24773 (6) | 1.00047 (7) | 0.0317 (2) | |
C6 | 0.25863 (19) | 0.3132 (2) | 0.2499 (3) | 0.0259 (6) | |
H6 | 0.2241 | 0.2669 | 0.1554 | 0.031* |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0224 (10) | 0.0271 (10) | 0.0112 (10) | 0.0031 (8) | 0.0033 (9) | −0.0010 (9) |
C1 | 0.0210 (12) | 0.0203 (11) | 0.0161 (12) | −0.0029 (9) | 0.0079 (10) | 0.0025 (10) |
O1 | 0.0246 (9) | 0.0287 (8) | 0.0135 (9) | 0.0002 (7) | 0.0063 (7) | −0.0022 (7) |
C2 | 0.0179 (11) | 0.0220 (11) | 0.0152 (12) | −0.0020 (9) | 0.0067 (9) | 0.0035 (9) |
C3 | 0.0295 (13) | 0.0221 (11) | 0.0153 (12) | −0.0033 (10) | 0.0100 (10) | 0.0011 (10) |
C4 | 0.0261 (13) | 0.0247 (12) | 0.0228 (13) | 0.0053 (10) | 0.0131 (11) | 0.0038 (10) |
C5 | 0.0184 (12) | 0.0322 (13) | 0.0237 (14) | 0.0022 (10) | 0.0056 (10) | 0.0041 (11) |
C7 | 0.0193 (12) | 0.0248 (12) | 0.0199 (12) | 0.0003 (9) | 0.0057 (10) | −0.0008 (10) |
C8 | 0.0195 (12) | 0.0229 (12) | 0.0134 (12) | 0.0015 (9) | 0.0048 (10) | 0.0052 (9) |
C9 | 0.0252 (13) | 0.0213 (12) | 0.0161 (12) | 0.0014 (9) | 0.0085 (10) | 0.0027 (10) |
C10 | 0.0226 (12) | 0.0285 (12) | 0.0138 (12) | −0.0027 (10) | 0.0043 (10) | 0.0043 (10) |
C11 | 0.0217 (12) | 0.0309 (13) | 0.0207 (13) | 0.0052 (10) | 0.0081 (10) | 0.0081 (11) |
C12 | 0.0329 (14) | 0.0221 (12) | 0.0244 (14) | 0.0059 (10) | 0.0129 (12) | 0.0040 (10) |
C13 | 0.0272 (13) | 0.0240 (12) | 0.0179 (12) | −0.0010 (10) | 0.0068 (10) | 0.0019 (10) |
Cl1 | 0.0246 (3) | 0.0376 (4) | 0.0256 (4) | 0.0006 (3) | −0.0013 (3) | −0.0033 (3) |
C6 | 0.0227 (13) | 0.0319 (13) | 0.0204 (13) | −0.0038 (11) | 0.0034 (10) | −0.0022 (11) |
N1—C1 | 1.356 (3) | C7—H7 | 0.9500 |
N1—C8 | 1.418 (3) | C8—C9 | 1.392 (3) |
N1—H1 | 0.88 (2) | C8—C13 | 1.396 (3) |
C1—O1 | 1.232 (2) | C9—C10 | 1.386 (3) |
C1—C2 | 1.499 (3) | C9—H9 | 0.9500 |
C2—C7 | 1.392 (3) | C10—C11 | 1.378 (3) |
C2—C3 | 1.394 (3) | C10—Cl1 | 1.745 (2) |
C3—C4 | 1.384 (3) | C11—C12 | 1.378 (3) |
C3—H3 | 0.9500 | C11—H11 | 0.9500 |
C4—C5 | 1.386 (3) | C12—C13 | 1.381 (3) |
C4—H4 | 0.9500 | C12—H12 | 0.9500 |
C5—C6 | 1.378 (3) | C13—H13 | 0.9500 |
C5—H5 | 0.9500 | C6—H6 | 0.9500 |
C7—C6 | 1.387 (3) | ||
C1—N1—C8 | 127.52 (19) | C9—C8—C13 | 119.9 (2) |
C1—N1—H1 | 117.3 (16) | C9—C8—N1 | 122.8 (2) |
C8—N1—H1 | 114.8 (16) | C13—C8—N1 | 117.3 (2) |
O1—C1—N1 | 122.8 (2) | C10—C9—C8 | 118.1 (2) |
O1—C1—C2 | 121.1 (2) | C10—C9—H9 | 121.0 |
N1—C1—C2 | 116.09 (19) | C8—C9—H9 | 121.0 |
C7—C2—C3 | 119.1 (2) | C11—C10—C9 | 122.9 (2) |
C7—C2—C1 | 123.4 (2) | C11—C10—Cl1 | 119.38 (18) |
C3—C2—C1 | 117.5 (2) | C9—C10—Cl1 | 117.77 (18) |
C4—C3—C2 | 120.1 (2) | C12—C11—C10 | 118.1 (2) |
C4—C3—H3 | 119.9 | C12—C11—H11 | 120.9 |
C2—C3—H3 | 119.9 | C10—C11—H11 | 120.9 |
C3—C4—C5 | 120.5 (2) | C11—C12—C13 | 121.0 (2) |
C3—C4—H4 | 119.8 | C11—C12—H12 | 119.5 |
C5—C4—H4 | 119.8 | C13—C12—H12 | 119.5 |
C6—C5—C4 | 119.6 (2) | C12—C13—C8 | 120.1 (2) |
C6—C5—H5 | 120.2 | C12—C13—H13 | 120.0 |
C4—C5—H5 | 120.2 | C8—C13—H13 | 120.0 |
C6—C7—C2 | 120.2 (2) | C5—C6—C7 | 120.4 (2) |
C6—C7—H7 | 119.9 | C5—C6—H6 | 119.8 |
C2—C7—H7 | 119.9 | C7—C6—H6 | 119.8 |
D—H···A | D—H | H···A | D···A | 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+1/2, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C13H10ClNO |
Mr | 231.67 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 90 |
a, b, c (Å) | 12.5598 (17), 10.2782 (14), 9.0788 (13) |
β (°) | 109.421 (5) |
V (Å3) | 1105.3 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.32 |
Crystal size (mm) | 0.57 × 0.22 × 0.03 |
Data collection | |
Diffractometer | Bruker APEXII CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2006) |
Tmin, Tmax | 0.743, 1.000 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6385, 2045, 1475 |
Rint | 0.047 |
(sin θ/λ)max (Å−1) | 0.606 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.041, 0.104, 1.04 |
No. of reflections | 2045 |
No. of parameters | 148 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 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).
D—H···A | D—H | H···A | D···A | 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) | 138.9 |
C13—H13···O1i | 0.95 | 2.71 | 3.301 (3) | 120.9 |
Symmetry code: (i) x, −y+1/2, z−1/2. |
Acknowledgements
We thank the University of Otago for purchase of the diffractometer.
References
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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.