organic compounds
A second monoclinic polymorph of 1-benzyl-N-methyl-1H-pyrrole-2-carboxamide
aDepartment of Chemistry, Jinan University, Guangzhou, Guangdong 510632, People's Republic of China
*Correspondence e-mail: xczeng@126.com, txush@jnu.edu.cn
In the title compound, C13H14N2O, the Npyrrole—C(H2)—C—C torsion angle is −7.7 (3)° and the dihedral angle between the pyrrole and benzene rings is 83.6 (2)°. In the crystal, intermolecular N—H⋯O hydrogen bonds link the molecules into chains extending along the c axis. We have previously reported another polymorphic form of this title compound, which has the same with different cell parameters: a = 9.8285 (18) Å, b = 23.588 (4) Å, c = 9.9230 (17) Å, β = 90.107 (3)°, Z = 8 and V = 2300.5 (7) Å3 [Zeng et al. (2010). Acta Cryst. E66, o2051].
Related literature
For details of the synthesis, see: Zeng et al. (2010); For the previously reported polymorph, see: Zeng et al. (2010) and for a related structure, see: Zeng et al. (2007).
Experimental
Crystal data
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Refinement
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Data collection: CrysAlis PRO (Oxford Diffraction, 2010); cell CrysAlis PRO; data reduction: CrysAlis PRO; 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
10.1107/S1600536811030364/zk2014sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536811030364/zk2014Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536811030364/zk2014Isup3.cml
The title compound was synthesized according to the literature procedure (Zeng et al., 2010). The product was dissolved in the mixture of ethanol / water (2:1 v/v), colorless crystals suitable for X-ray analysis were obtained over a period of five days by slow evaporation at room temperature of the solution.
All non-H atoms were refined with anisotropic displacement parameters. The H atoms were positioned geometrically [C—H = 0.97Å for CH2, 0.96Å for CH3, 0.93Å for CH(aromatic) and N—H = 0.86 Å] and refined using a riding model, with Uiso = 1.2Ueq (1.5Ueq for the methyl group) of the parent atom.
Data collection: CrysAlis PRO (Oxford Diffraction, 2010); cell
CrysAlis PRO (Oxford Diffraction, 2010); data reduction: CrysAlis PRO (Oxford Diffraction, 2010); 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).C13H14N2O | Dx = 1.220 Mg m−3 |
Mr = 214.26 | Melting point: 360 K |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 5.4326 (4) Å | Cell parameters from 1936 reflections |
b = 22.5218 (16) Å | θ = 3.5–29.2° |
c = 9.7358 (5) Å | µ = 0.08 mm−1 |
β = 101.676 (6)° | T = 293 K |
V = 1166.55 (13) Å3 | Prism, colorless |
Z = 4 | 0.50 × 0.28 × 0.19 mm |
F(000) = 456 |
Oxford Gemini S Ultra area-detector diffractometer | 2504 independent reflections |
Radiation source: fine-focus sealed tube | 1597 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.025 |
ϕ and ω scans | θmax = 27.0°, θmin = 3.5° |
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010) | h = −6→6 |
Tmin = 0.962, Tmax = 0.985 | k = −28→22 |
5327 measured reflections | l = −12→11 |
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)] = 0.063 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.169 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | w = 1/[σ2(Fo2) + (0.0629P)2 + 0.3194P] where P = (Fo2 + 2Fc2)/3 |
2504 reflections | (Δ/σ)max = 0.004 |
150 parameters | Δρmax = 0.17 e Å−3 |
0 restraints | Δρmin = −0.16 e Å−3 |
C13H14N2O | V = 1166.55 (13) Å3 |
Mr = 214.26 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 5.4326 (4) Å | µ = 0.08 mm−1 |
b = 22.5218 (16) Å | T = 293 K |
c = 9.7358 (5) Å | 0.50 × 0.28 × 0.19 mm |
β = 101.676 (6)° |
Oxford Gemini S Ultra area-detector diffractometer | 2504 independent reflections |
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010) | 1597 reflections with I > 2σ(I) |
Tmin = 0.962, Tmax = 0.985 | Rint = 0.025 |
5327 measured reflections |
R[F2 > 2σ(F2)] = 0.063 | 0 restraints |
wR(F2) = 0.169 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | Δρmax = 0.17 e Å−3 |
2504 reflections | Δρmin = −0.16 e Å−3 |
150 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 | ||
C5 | 0.0889 (4) | 0.28312 (9) | 0.60936 (19) | 0.0517 (5) | |
C4 | 0.2716 (4) | 0.32716 (10) | 0.6779 (2) | 0.0543 (5) | |
N1 | 0.4311 (3) | 0.35726 (9) | 0.6084 (2) | 0.0652 (5) | |
O1 | 0.0465 (4) | 0.27429 (8) | 0.48276 (15) | 0.0877 (6) | |
N2 | −0.0360 (4) | 0.25434 (9) | 0.6916 (2) | 0.0688 (6) | |
C8 | 0.2613 (4) | 0.39425 (10) | 0.3667 (2) | 0.0590 (6) | |
C7 | 0.4436 (5) | 0.35414 (12) | 0.4599 (2) | 0.0729 (7) | |
H7A | 0.4117 | 0.3135 | 0.4281 | 0.088* | |
H7B | 0.6127 | 0.3643 | 0.4501 | 0.088* | |
C9 | 0.0783 (4) | 0.42544 (11) | 0.4135 (3) | 0.0681 (6) | |
H9 | 0.0665 | 0.4229 | 0.5073 | 0.082* | |
C3 | 0.3192 (5) | 0.34701 (11) | 0.8140 (2) | 0.0719 (7) | |
H3 | 0.2398 | 0.3342 | 0.8848 | 0.086* | |
C1 | 0.5712 (5) | 0.39542 (13) | 0.6999 (3) | 0.0870 (8) | |
H1 | 0.6916 | 0.4213 | 0.6787 | 0.104* | |
C11 | −0.0747 (6) | 0.46500 (12) | 0.1851 (3) | 0.0847 (8) | |
H11 | −0.1872 | 0.4888 | 0.1244 | 0.102* | |
C6 | −0.2303 (5) | 0.21166 (12) | 0.6402 (3) | 0.0819 (8) | |
H6A | −0.3890 | 0.2266 | 0.6541 | 0.123* | |
H6B | −0.1930 | 0.1750 | 0.6903 | 0.123* | |
H6C | −0.2385 | 0.2050 | 0.5420 | 0.123* | |
C12 | 0.1055 (6) | 0.43425 (15) | 0.1372 (3) | 0.0962 (9) | |
H12 | 0.1160 | 0.4368 | 0.0432 | 0.115* | |
C10 | −0.0895 (5) | 0.46073 (12) | 0.3229 (3) | 0.0799 (7) | |
H10 | −0.2130 | 0.4816 | 0.3561 | 0.096* | |
C13 | 0.2726 (5) | 0.39933 (13) | 0.2273 (3) | 0.0830 (8) | |
H13 | 0.3960 | 0.3787 | 0.1933 | 0.100* | |
C2 | 0.5084 (5) | 0.38987 (14) | 0.8271 (3) | 0.0911 (9) | |
H2 | 0.5783 | 0.4107 | 0.9080 | 0.109* | |
H2A | 0.002 (5) | 0.2599 (12) | 0.781 (3) | 0.092 (9)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C5 | 0.0605 (12) | 0.0601 (13) | 0.0343 (9) | 0.0096 (10) | 0.0092 (8) | 0.0024 (9) |
C4 | 0.0544 (12) | 0.0661 (13) | 0.0408 (10) | 0.0075 (10) | 0.0060 (8) | 0.0031 (9) |
N1 | 0.0503 (10) | 0.0815 (14) | 0.0631 (11) | 0.0025 (10) | 0.0095 (9) | 0.0076 (10) |
O1 | 0.1194 (15) | 0.1092 (14) | 0.0364 (8) | −0.0265 (12) | 0.0205 (8) | −0.0120 (8) |
N2 | 0.0875 (15) | 0.0786 (14) | 0.0402 (10) | −0.0144 (11) | 0.0126 (10) | 0.0021 (10) |
C8 | 0.0509 (12) | 0.0652 (14) | 0.0648 (13) | −0.0049 (10) | 0.0206 (10) | 0.0075 (11) |
C7 | 0.0605 (14) | 0.0972 (19) | 0.0682 (14) | 0.0108 (13) | 0.0297 (11) | 0.0171 (13) |
C9 | 0.0659 (14) | 0.0742 (15) | 0.0658 (14) | 0.0021 (12) | 0.0176 (11) | 0.0046 (12) |
C3 | 0.0807 (17) | 0.0841 (17) | 0.0457 (12) | 0.0007 (14) | 0.0000 (11) | −0.0033 (11) |
C1 | 0.0592 (15) | 0.097 (2) | 0.096 (2) | −0.0110 (14) | −0.0053 (14) | 0.0067 (17) |
C11 | 0.091 (2) | 0.0721 (17) | 0.0839 (19) | 0.0001 (15) | 0.0011 (15) | 0.0179 (14) |
C6 | 0.0880 (19) | 0.0753 (17) | 0.0811 (17) | −0.0126 (14) | 0.0140 (14) | 0.0068 (13) |
C12 | 0.107 (2) | 0.114 (2) | 0.0689 (17) | 0.005 (2) | 0.0211 (16) | 0.0241 (17) |
C10 | 0.0772 (17) | 0.0731 (16) | 0.0878 (18) | 0.0086 (14) | 0.0127 (14) | −0.0016 (15) |
C13 | 0.0811 (18) | 0.103 (2) | 0.0721 (16) | 0.0089 (16) | 0.0330 (14) | 0.0104 (15) |
C2 | 0.0860 (19) | 0.097 (2) | 0.0756 (18) | −0.0090 (17) | −0.0194 (15) | −0.0136 (16) |
C5—O1 | 1.223 (2) | C3—C2 | 1.397 (4) |
C5—N2 | 1.320 (3) | C3—H3 | 0.9300 |
C5—C4 | 1.465 (3) | C1—C2 | 1.355 (4) |
C4—C3 | 1.372 (3) | C1—H1 | 0.9300 |
C4—N1 | 1.381 (3) | C11—C12 | 1.356 (4) |
N1—C1 | 1.356 (3) | C11—C10 | 1.363 (4) |
N1—C7 | 1.462 (3) | C11—H11 | 0.9300 |
N2—C6 | 1.440 (3) | C6—H6A | 0.9600 |
N2—H2A | 0.86 (3) | C6—H6B | 0.9600 |
C8—C9 | 1.369 (3) | C6—H6C | 0.9600 |
C8—C13 | 1.376 (3) | C12—C13 | 1.374 (4) |
C8—C7 | 1.502 (3) | C12—H12 | 0.9300 |
C7—H7A | 0.9700 | C10—H10 | 0.9300 |
C7—H7B | 0.9700 | C13—H13 | 0.9300 |
C9—C10 | 1.384 (3) | C2—H2 | 0.9300 |
C9—H9 | 0.9300 | ||
O1—C5—N2 | 121.1 (2) | C2—C3—H3 | 126.1 |
O1—C5—C4 | 122.79 (19) | C2—C1—N1 | 109.3 (2) |
N2—C5—C4 | 116.09 (18) | C2—C1—H1 | 125.4 |
C3—C4—N1 | 107.4 (2) | N1—C1—H1 | 125.4 |
C3—C4—C5 | 129.7 (2) | C12—C11—C10 | 119.5 (3) |
N1—C4—C5 | 122.89 (17) | C12—C11—H11 | 120.3 |
C1—N1—C4 | 108.3 (2) | C10—C11—H11 | 120.3 |
C1—N1—C7 | 123.2 (2) | N2—C6—H6A | 109.5 |
C4—N1—C7 | 128.4 (2) | N2—C6—H6B | 109.5 |
C5—N2—C6 | 123.2 (2) | H6A—C6—H6B | 109.5 |
C5—N2—H2A | 119.7 (19) | N2—C6—H6C | 109.5 |
C6—N2—H2A | 117.1 (18) | H6A—C6—H6C | 109.5 |
C9—C8—C13 | 117.8 (2) | H6B—C6—H6C | 109.5 |
C9—C8—C7 | 122.8 (2) | C11—C12—C13 | 120.2 (3) |
C13—C8—C7 | 119.4 (2) | C11—C12—H12 | 119.9 |
N1—C7—C8 | 114.28 (19) | C13—C12—H12 | 119.9 |
N1—C7—H7A | 108.7 | C11—C10—C9 | 120.4 (3) |
C8—C7—H7A | 108.7 | C11—C10—H10 | 119.8 |
N1—C7—H7B | 108.7 | C9—C10—H10 | 119.8 |
C8—C7—H7B | 108.7 | C12—C13—C8 | 121.4 (3) |
H7A—C7—H7B | 107.6 | C12—C13—H13 | 119.3 |
C8—C9—C10 | 120.8 (2) | C8—C13—H13 | 119.3 |
C8—C9—H9 | 119.6 | C1—C2—C3 | 107.3 (2) |
C10—C9—H9 | 119.6 | C1—C2—H2 | 126.3 |
C4—C3—C2 | 107.7 (2) | C3—C2—H2 | 126.3 |
C4—C3—H3 | 126.1 | ||
O1—C5—C4—C3 | 171.6 (2) | C13—C8—C9—C10 | 0.1 (4) |
N2—C5—C4—C3 | −6.1 (3) | C7—C8—C9—C10 | −178.4 (2) |
O1—C5—C4—N1 | −7.8 (3) | N1—C4—C3—C2 | 0.4 (3) |
N2—C5—C4—N1 | 174.51 (19) | C5—C4—C3—C2 | −179.1 (2) |
C3—C4—N1—C1 | −0.8 (3) | C4—N1—C1—C2 | 1.0 (3) |
C5—C4—N1—C1 | 178.7 (2) | C7—N1—C1—C2 | 176.9 (2) |
C3—C4—N1—C7 | −176.4 (2) | C10—C11—C12—C13 | −0.4 (5) |
C5—C4—N1—C7 | 3.0 (3) | C12—C11—C10—C9 | 0.2 (4) |
O1—C5—N2—C6 | −0.7 (4) | C8—C9—C10—C11 | −0.1 (4) |
C4—C5—N2—C6 | 177.0 (2) | C11—C12—C13—C8 | 0.5 (5) |
C1—N1—C7—C8 | −90.4 (3) | C9—C8—C13—C12 | −0.3 (4) |
C4—N1—C7—C8 | 84.7 (3) | C7—C8—C13—C12 | 178.3 (3) |
C9—C8—C7—N1 | −7.7 (3) | N1—C1—C2—C3 | −0.7 (3) |
C13—C8—C7—N1 | 173.8 (2) | C4—C3—C2—C1 | 0.2 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2A···O1i | 0.86 (3) | 2.08 (3) | 2.852 (2) | 149 (2) |
Symmetry code: (i) x, −y+1/2, z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C13H14N2O |
Mr | 214.26 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 293 |
a, b, c (Å) | 5.4326 (4), 22.5218 (16), 9.7358 (5) |
β (°) | 101.676 (6) |
V (Å3) | 1166.55 (13) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.50 × 0.28 × 0.19 |
Data collection | |
Diffractometer | Oxford Gemini S Ultra area-detector diffractometer |
Absorption correction | Multi-scan (CrysAlis PRO; Oxford Diffraction, 2010) |
Tmin, Tmax | 0.962, 0.985 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 5327, 2504, 1597 |
Rint | 0.025 |
(sin θ/λ)max (Å−1) | 0.639 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.063, 0.169, 1.02 |
No. of reflections | 2504 |
No. of parameters | 150 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.17, −0.16 |
Computer programs: CrysAlis PRO (Oxford Diffraction, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2A···O1i | 0.86 (3) | 2.08 (3) | 2.852 (2) | 149 (2) |
Symmetry code: (i) x, −y+1/2, z+1/2. |
Acknowledgements
We thank the Natural Science Foundation of Guangdong Province, China (No. 06300581) for generously supporting this study.
References
Oxford Diffraction (2010). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Zeng, X. C., Li, K. P., Hu, F. & Zheng, L. (2010). Acta Cryst. E66, o2051. Web of Science CSD CrossRef IUCr Journals Google Scholar
Zeng, X.-C., Zeng, J., Li, X. & Ling, X. (2007). Acta Cryst. E63, o3424. Web of Science CSD CrossRef IUCr Journals Google Scholar
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This study is related to our previous structural investigations of 1-Benzyl-N-methyl-1H-pyrrole-2-carboxamide, I, (Zeng et al., 2010) and methyl 2-(4,5-dibromo-1H-pyrrole-2-carboxamido)propionate (Zeng et al., 2007)
In I (Fig. 1), the bond lengths and angles are almost same as those observed in the previously reported polymorphic form (Zeng et al., 2010). In the crystal structure, the molecules are linked through N—H···O hydrogen bonds, forming chains extending to the c axis (shown in Fig. 2).
It is interesting to note here that the previously reported form was crystallized from an ethanol solution (Zeng et al., 2010), while the present form was crystallized from the solution of ethanol/water (2:1 v/v). Although these two polymorphs have the same space group (P21/c), their unit-cell parameters and melting point are different. For the previous one, the unit-cell parameters are a = 9.8285 (18), b = 23.588 (4), c = 9.9230 (17) Å, beta = 90.107 (3)°, with Z = 8, V = 2300.5 (7) and m.p. = 365 K. For the present one, they are 5.4326 (4), 22.5218 (16), 9.7358 (5) Å, 101.676 (6)°, Z = 4, V = 1166.55 (13) and m.p. = 360 K.
As reported, the previous polymorph structure show that the asymmetric unit of the compound contains two independent molecules, which differ in the twist of the phenyl ring: the Npyrrole—C(H2)—C—C torsion angles are -73.0 (3)° and 17.1 (3)°, respectively. And for the present one, the asymmetric unit contains just one molecule, in this molecule, the Npyrrole—C(H2)—C—C torsion angle is -7.7 (3)°, the dihedral angle between the pyrrole plane and the benzene plane is 83.60 (2)°.
The crystal packings of these two structures are differences also. In the previous polymorph structure, molecules are linked through N—H···O hydrogen bonds, generating chains extending to the a axis (shown in Fig. 3). And for the present one, N—H···O hydrogen bonds link molecules together to forming chains extending to the c axis (shown in Fig. 2).