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ISSN: 2056-9890

N-(2-Meth­­oxy­phen­yl)phthalamic acid

aCavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, England
*Correspondence e-mail: jmc61@cam.ac.uk

(Received 25 April 2013; accepted 15 May 2013; online 22 May 2013)

The title compound, C14H13NO3, adopts a twisted conformation in the crystal, with an inter­planar angle between the two benzene rings of 87.30 (5)°. Mol­ecules within the structure are linked via O—H⋯O inter­actions, forming a hydrogen-bonded chain motif with graph set C(7) along the glide plane in the [001] direction.

Related literature

For related phthalamic acid structures, see: Smith et al. (1983[Smith, G., Kennard, C. H. L. & Katekar, G. F. (1983). Aust. J. Chem. 36, 2455-2463.]) and Bocelli et al. (1989[Bocelli, G., Rizzoli, C. & Ori, O. (1989). Z. Kristallogr. 189, 301-316.]). For the structure of a diaryl amide containing the 2-meth­oxy­phenyl moeity, see: Parra et al. (2001[Parra, R. D., Zeng, H., Zhu, J., Zheng, C., Zeng, X. C. & Gong, B. (2001). Chem. Eur. J. 7, 4352-4357.]). A description of hydrogen bonding in terms of graph sets is given by Etter (1990[Etter, M. C. (1990). Acc. Chem. Res. 23, 121-126.]) and Bernstein et al. (1995)[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]. For standard bond lengths as calculated using crystal structure data, see Allen et al. (2006[Allen, F. H., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (2006). International Tables for Crystallography, Vol. C, ch. 9.5, pp. 790-811. International Union of Crystallography.]).

[Scheme 1]

Experimental

Crystal data
  • C15H13NO4

  • Mr = 271.26

  • Monoclinic, P 21 /c

  • a = 9.038 (4) Å

  • b = 14.237 (5) Å

  • c = 10.405 (4) Å

  • β = 107.456 (5)°

  • V = 1277.2 (9) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 120 K

  • 0.53 × 0.18 × 0.09 mm

Data collection
  • Rigaku Saturn724+ diffractometer

  • Absorption correction: multi-scan (ABSCOR; Higashi, 1995[Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.978, Tmax = 0.991

  • 9056 measured reflections

  • 2904 independent reflections

  • 2687 reflections with I > 2σ(I)

  • Rint = 0.034

Refinement
  • R[F2 > 2σ(F2)] = 0.044

  • wR(F2) = 0.111

  • S = 1.09

  • 2904 reflections

  • 233 parameters

  • All H-atom parameters refined

  • Δρmax = 0.30 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1O⋯O3i 0.97 (3) 1.72 (3) 2.6837 (16) 175 (2)
Symmetry code: (i) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: CrystalClear-SM Expert (Rigaku, 2009[Rigaku (2009). CrystalClear-SM Expert. Rigaku Corporation, The Woodlands, Texas, USA.]); cell refinement: CrystalClear-SM Expert; data reduction: CrystalClear-SM Expert; 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.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information


Comment top

Molecules of the title compound (Fig. 1.) exhibit a conformation wherein the interplanar angle between the two phenyl rings is observed to be 87.30 (5)°. The 2-methoxy-substituted ring is in almost perfect alignment with the amide moiety, the interplanar angle between the two being 3.23 (15)°. However, the twisted conformation is due to the almost 90° interplanar angle between the amide and the carboxy-substituted phenyl ring (89.81 (8)°). This conformation is similar to that observed in the structure of N-(2-phenyl)phthalamic acid (Smith et al. 1983; Bocelli et al. 1989). It should also be noted that a more planar conformation is observed where an intramolecular hydrogen bond can be formed between the hydrogen of the amide moiety and a hydrogen bond acceptor at the 2-position of the ring adjacent to the amide carbonyl, as is observed in N-(2-methoxyphenyl)-2-methoxybenzamide (Parra et al. 2001).

An intermolecular hydrogen bond is observed in the interaction between O1, in the carboxylic acid moiety of one molecule (acting as the hydrogen bond donor), and O3, the amide carbonyl of an adjacent molecule (which acts as the acceptor). This O1—H1O···O3 hydrogen bond (1.72 (3) Å) links the molecules along the crystallographic <001> direction (Fig. 2.) and, as a result, the molecules in the chain are related by the glide plane symmetry element along the c axis. It is worth noting that despite the presence of four oxygen atoms, all of which have the potential to act as hydrogen bond acceptors, the amide proton, H1N, does not form a hydrogen bond in this structure; a rare exception to Etter's first rule (Etter, 1990). In this case, a number of weak C—H···O hydrogen bonds form in preference, with the carbon atoms of the aromatic rings and their associated protons acting as the hydrogen bond donors.

Within the molecule itself, there are four distinct oxygen atom environments. The carboxylic acid oxygen atoms, O1 and O2, exhibit bond lengths to the carbon atom of the acid group within two standard deviations of the International Tables for Crystallography value (Allen et al. 2006) demonstrating distinct single and double bond character respectively. This suggests very little resonance-related charge seperation across the carboxylic acid group in this molecule. The same cannot be said of the amide moeity, however, as the carbonyl bond is longer in this case due to resonance between O3 and N1. This is a far from unexpected development as the C8—O3 bond length is close to the average for bonds of this type. There is no resonance form for this molecule associated with a change in the bond lengths to O4 and hence these bond lengths are also in agreement with the International Tables for Crystallography values.

Related literature top

For related phthalamic acid structures, see: Smith et al. (1983) and Bocelli et al. (1989). For the structure of a diaryl amide containing the 2-methoxyphenyl moeity, see: Parra et al. (2001). A description of hydrogen bonding in terms of graph sets is given by Etter (1990) and Bernstein et al. (1995). For standard bond lengths as calculated using crystal structure data, see Allen et al. (2006).

Experimental top

N-(2-methoxyphenyl)phthalamic acid was obtained from Sigma-Aldrich. Crystals suitable for single-crystal X-ray crystallography were grown via evaporation of the solvent from a solution of the product in methanol.

Refinement top

H atoms were located from the Fourier difference map of electron density and refined freely. The most disagreeable reflections were omitted; three reflections exhibiting a Δ(F2) value greater than 5 su were removed.

Computing details top

Data collection: CrystalClear-SM Expert (Rigaku, 2009); cell refinement: CrystalClear-SM Expert (Rigaku, 2009); data reduction: CrystalClear-SM Expert (Rigaku, 2009); 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: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the title compound with displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. View of the C(7) hydrogen bond (dashed lines) motif in the [001] direction in the structure of the title compound. Carbon-bonded hydrogen atoms are omitted for clarity.
2-[(2-Methoxyphenyl)carbamoyl]benzoic acid top
Crystal data top
C15H13NO4F(000) = 568
Mr = 271.26Dx = 1.411 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3461 reflections
a = 9.038 (4) Åθ = 2.5–33.2°
b = 14.237 (5) ŵ = 0.10 mm1
c = 10.405 (4) ÅT = 120 K
β = 107.456 (5)°Prism, colorless
V = 1277.2 (9) Å30.53 × 0.18 × 0.09 mm
Z = 4
Data collection top
Rigaku Saturn724+
diffractometer
2904 independent reflections
Radiation source: Sealed Tube2687 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
Detector resolution: 28.5714 pixels mm-1θmax = 27.5°, θmin = 3.8°
profile data from ω–scansh = 1111
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
k = 1818
Tmin = 0.978, Tmax = 0.991l = 813
9056 measured reflections
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)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.111All H-atom parameters refined
S = 1.09 w = 1/[σ2(Fo2) + (0.0518P)2 + 0.4728P]
where P = (Fo2 + 2Fc2)/3
2904 reflections(Δ/σ)max < 0.001
233 parametersΔρmax = 0.30 e Å3
0 restraintsΔρmin = 0.20 e Å3
Crystal data top
C15H13NO4V = 1277.2 (9) Å3
Mr = 271.26Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.038 (4) ŵ = 0.10 mm1
b = 14.237 (5) ÅT = 120 K
c = 10.405 (4) Å0.53 × 0.18 × 0.09 mm
β = 107.456 (5)°
Data collection top
Rigaku Saturn724+
diffractometer
2904 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
2687 reflections with I > 2σ(I)
Tmin = 0.978, Tmax = 0.991Rint = 0.034
9056 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0440 restraints
wR(F2) = 0.111All H-atom parameters refined
S = 1.09Δρmax = 0.30 e Å3
2904 reflectionsΔρmin = 0.20 e Å3
233 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
C10.38628 (15)0.07876 (9)0.59059 (13)0.0212 (3)
C20.45227 (14)0.03553 (9)0.71557 (13)0.0204 (3)
C30.42309 (16)0.05935 (9)0.73260 (14)0.0230 (3)
C40.32498 (17)0.10968 (9)0.62659 (14)0.0258 (3)
C50.25493 (17)0.06637 (10)0.50393 (14)0.0261 (3)
C60.28625 (16)0.02755 (10)0.48532 (13)0.0239 (3)
C70.42837 (15)0.17822 (9)0.57121 (13)0.0221 (3)
C80.55286 (15)0.08745 (9)0.83745 (13)0.0209 (3)
C90.83209 (15)0.12208 (9)0.95264 (13)0.0228 (3)
C100.97791 (16)0.11002 (9)0.93125 (14)0.0243 (3)
C111.11088 (17)0.14262 (10)1.02478 (15)0.0299 (3)
C121.09965 (19)0.18763 (11)1.14052 (16)0.0356 (4)
C130.95702 (19)0.20079 (10)1.16090 (15)0.0325 (3)
C140.82184 (17)0.16842 (10)1.06717 (14)0.0264 (3)
C151.11647 (18)0.05563 (12)0.78206 (18)0.0324 (3)
N10.70557 (13)0.08237 (8)0.85182 (12)0.0237 (2)
O10.37604 (13)0.20728 (7)0.44416 (10)0.0297 (2)
O20.50580 (14)0.22662 (7)0.66190 (11)0.0353 (3)
O30.49670 (11)0.12378 (7)0.91995 (9)0.0251 (2)
O40.97329 (11)0.06458 (7)0.81392 (10)0.0278 (2)
H1N0.731 (2)0.0563 (13)0.7835 (19)0.034 (5)*
H1O0.425 (3)0.2672 (18)0.440 (2)0.062 (7)*
H30.481 (2)0.0877 (12)0.8217 (19)0.032 (4)*
H40.304 (2)0.1725 (13)0.6414 (17)0.028 (4)*
H50.185 (2)0.1009 (13)0.4320 (18)0.032 (4)*
H60.2416 (18)0.0616 (11)0.4002 (16)0.019 (4)*
H111.209 (2)0.1333 (13)1.0088 (18)0.037 (5)*
H121.194 (3)0.2081 (15)1.203 (2)0.048 (6)*
H130.944 (2)0.2302 (13)1.2380 (19)0.035 (5)*
H140.728 (2)0.1778 (12)1.0829 (17)0.026 (4)*
H15A1.088 (2)0.0212 (14)0.694 (2)0.044 (5)*
H15B1.158 (2)0.1163 (14)0.7720 (19)0.039 (5)*
H15C1.192 (2)0.0199 (13)0.8516 (18)0.033 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0216 (6)0.0207 (6)0.0216 (6)0.0001 (5)0.0070 (5)0.0006 (5)
C20.0187 (6)0.0220 (6)0.0215 (6)0.0009 (5)0.0074 (5)0.0014 (5)
C30.0226 (6)0.0225 (6)0.0230 (6)0.0005 (5)0.0051 (5)0.0006 (5)
C40.0277 (7)0.0205 (6)0.0294 (7)0.0033 (5)0.0090 (6)0.0023 (5)
C50.0264 (7)0.0257 (6)0.0243 (7)0.0045 (5)0.0050 (5)0.0058 (5)
C60.0245 (7)0.0259 (6)0.0202 (6)0.0001 (5)0.0051 (5)0.0014 (5)
C70.0229 (6)0.0211 (6)0.0217 (6)0.0006 (5)0.0056 (5)0.0003 (5)
C80.0227 (6)0.0185 (5)0.0202 (6)0.0010 (5)0.0047 (5)0.0006 (5)
C90.0242 (7)0.0199 (6)0.0211 (6)0.0019 (5)0.0020 (5)0.0019 (5)
C100.0263 (7)0.0210 (6)0.0240 (6)0.0002 (5)0.0051 (5)0.0038 (5)
C110.0236 (7)0.0285 (7)0.0333 (8)0.0028 (5)0.0020 (6)0.0045 (6)
C120.0324 (8)0.0316 (7)0.0329 (8)0.0074 (6)0.0052 (6)0.0002 (6)
C130.0429 (9)0.0263 (7)0.0241 (7)0.0045 (6)0.0034 (6)0.0052 (6)
C140.0294 (7)0.0239 (6)0.0246 (7)0.0011 (5)0.0059 (6)0.0009 (5)
C150.0252 (7)0.0351 (8)0.0393 (9)0.0056 (6)0.0134 (6)0.0062 (7)
N10.0217 (6)0.0283 (6)0.0207 (6)0.0011 (4)0.0058 (4)0.0063 (4)
O10.0356 (6)0.0259 (5)0.0240 (5)0.0053 (4)0.0036 (4)0.0033 (4)
O20.0497 (7)0.0240 (5)0.0263 (5)0.0099 (4)0.0026 (5)0.0002 (4)
O30.0253 (5)0.0269 (5)0.0238 (5)0.0014 (4)0.0083 (4)0.0054 (4)
O40.0225 (5)0.0342 (5)0.0277 (5)0.0002 (4)0.0091 (4)0.0024 (4)
Geometric parameters (Å, º) top
C1—C61.3980 (19)C9—C101.411 (2)
C1—C21.4001 (18)C9—N11.4171 (17)
C1—C71.4955 (18)C10—O41.3711 (17)
C2—C31.3977 (19)C10—C111.380 (2)
C2—C81.5131 (18)C11—C121.394 (2)
C3—C41.3891 (19)C11—H110.961 (19)
C3—H31.002 (18)C12—C131.381 (2)
C4—C51.387 (2)C12—H120.95 (2)
C4—H40.937 (18)C13—C141.393 (2)
C5—C61.392 (2)C13—H130.942 (19)
C5—H50.956 (19)C14—H140.920 (17)
C6—H60.984 (16)C15—O41.4346 (18)
C7—O21.2079 (17)C15—H15A1.00 (2)
C7—O11.3293 (17)C15—H15B0.96 (2)
C8—O31.2343 (16)C15—H15C0.975 (19)
C8—N11.3449 (19)N1—H1N0.889 (19)
C9—C141.389 (2)O1—H1O0.97 (3)
C6—C1—C2119.58 (12)O4—C10—C11125.02 (13)
C6—C1—C7121.26 (12)O4—C10—C9114.67 (12)
C2—C1—C7119.13 (12)C11—C10—C9120.31 (13)
C3—C2—C1119.91 (12)C10—C11—C12119.33 (14)
C3—C2—C8117.04 (11)C10—C11—H11119.1 (11)
C1—C2—C8123.03 (12)C12—C11—H11121.6 (12)
C4—C3—C2119.84 (12)C13—C12—C11120.55 (14)
C4—C3—H3123.9 (10)C13—C12—H12122.4 (13)
C2—C3—H3116.2 (10)C11—C12—H12117.1 (13)
C5—C4—C3120.51 (13)C12—C13—C14120.71 (15)
C5—C4—H4121.1 (11)C12—C13—H13123.3 (11)
C3—C4—H4118.3 (11)C14—C13—H13115.9 (11)
C4—C5—C6119.94 (13)C9—C14—C13119.17 (14)
C4—C5—H5120.2 (11)C9—C14—H14121.5 (11)
C6—C5—H5119.9 (11)C13—C14—H14119.3 (11)
C5—C6—C1120.17 (13)O4—C15—H15A104.6 (12)
C5—C6—H6123.6 (9)O4—C15—H15B110.8 (11)
C1—C6—H6116.2 (9)H15A—C15—H15B110.0 (16)
O2—C7—O1123.32 (12)O4—C15—H15C110.7 (11)
O2—C7—C1123.10 (12)H15A—C15—H15C110.7 (16)
O1—C7—C1113.56 (11)H15B—C15—H15C110.0 (16)
O3—C8—N1124.58 (12)C8—N1—C9129.36 (12)
O3—C8—C2121.24 (12)C8—N1—H1N115.7 (12)
N1—C8—C2113.92 (11)C9—N1—H1N114.5 (12)
C14—C9—C10119.92 (13)C7—O1—H1O106.7 (14)
C14—C9—N1125.29 (13)C10—O4—C15117.33 (12)
C10—C9—N1114.78 (12)
C6—C1—C2—C32.71 (19)C1—C2—C8—N193.21 (15)
C7—C1—C2—C3175.39 (12)C14—C9—C10—O4179.05 (12)
C6—C1—C2—C8175.73 (12)N1—C9—C10—O42.14 (16)
C7—C1—C2—C86.17 (18)C14—C9—C10—C111.1 (2)
C1—C2—C3—C41.92 (19)N1—C9—C10—C11177.70 (12)
C8—C2—C3—C4176.61 (12)O4—C10—C11—C12179.85 (13)
C2—C3—C4—C50.3 (2)C9—C10—C11—C120.0 (2)
C3—C4—C5—C61.8 (2)C10—C11—C12—C130.9 (2)
C4—C5—C6—C11.0 (2)C11—C12—C13—C140.8 (2)
C2—C1—C6—C51.3 (2)C10—C9—C14—C131.2 (2)
C7—C1—C6—C5176.80 (12)N1—C9—C14—C13177.44 (13)
C6—C1—C7—O2174.83 (14)C12—C13—C14—C90.3 (2)
C2—C1—C7—O27.1 (2)O3—C8—N1—C95.9 (2)
C6—C1—C7—O16.92 (18)C2—C8—N1—C9179.87 (12)
C2—C1—C7—O1171.15 (11)C14—C9—N1—C86.6 (2)
C3—C2—C8—O386.11 (16)C10—C9—N1—C8174.66 (13)
C1—C2—C8—O392.37 (16)C11—C10—O4—C154.18 (19)
C3—C2—C8—N188.31 (14)C9—C10—O4—C15176.00 (12)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1O···O3i0.97 (3)1.72 (3)2.6837 (16)175 (2)
Symmetry code: (i) x, y+1/2, z1/2.

Experimental details

Crystal data
Chemical formulaC15H13NO4
Mr271.26
Crystal system, space groupMonoclinic, P21/c
Temperature (K)120
a, b, c (Å)9.038 (4), 14.237 (5), 10.405 (4)
β (°) 107.456 (5)
V3)1277.2 (9)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.53 × 0.18 × 0.09
Data collection
DiffractometerRigaku Saturn724+
diffractometer
Absorption correctionMulti-scan
(ABSCOR; Higashi, 1995)
Tmin, Tmax0.978, 0.991
No. of measured, independent and
observed [I > 2σ(I)] reflections
9056, 2904, 2687
Rint0.034
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.044, 0.111, 1.09
No. of reflections2904
No. of parameters233
H-atom treatmentAll H-atom parameters refined
Δρmax, Δρmin (e Å3)0.30, 0.20

Computer programs: CrystalClear-SM Expert (Rigaku, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), WinGX (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1O···O3i0.97 (3)1.72 (3)2.6837 (16)175 (2)
Symmetry code: (i) x, y+1/2, z1/2.
 

Footnotes

Other affiliation: Department of Chemistry, University of New Brunswick, Fredericton, NB, Canada E3B 5A3.

Acknowledgements

JMC thanks the Royal Society for a University Research Fellowship, the University of New Brunswick for the UNB Vice-Chancellor's Research Chair, and NSERC for the Discovery Grant 355708 (for PGW).

References

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