organic compounds
N-(2,4,6-Trimethylphenyl)maleamic acid
aDepartment of Chemistry, Mangalore University, Mangalagangotri 574 199, Mangalore, India, bFaculty of Chemical and Food Technology, Slovak Technical University, Radlinského 9, SK-812 37 Bratislava, Slovak Republic, and cInstitute of Materials Science, Darmstadt University of Technology, Petersenstrasse 23, D-64287 Darmstadt, Germany
*Correspondence e-mail: gowdabt@yahoo.com
The molecular structure of the title compound, C13H15NO3, is stabilized by a short intramolecular O—H⋯O hydrogen bond within the maleamic unit. In the crystal, intermolecular N—H⋯O hydrogen bonds link molecules into zigzag chains propagating in [010].
Related literature
For our sudies on the effect of ring- and side-chain substitutions on the crystal structures of et al. (2009); Gowda, Tokarčík et al. (2009a,b); Lo & Ng (2009). For hydrogen bonds in see: Leiserowitz (1976).
see: Gowda, ForoExperimental
Crystal data
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Refinement
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Data collection: CrysAlis Pro (Oxford Diffraction, 2009); 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: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2002); software used to prepare material for publication: SHELXL97, PLATON (Spek, 2009) and WinGX (Farrugia, 1999).
Supporting information
https://doi.org/10.1107/S1600536809044754/bt5119sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536809044754/bt5119Isup2.hkl
The solution of maleic anhydride (0.025 mol) in toluene (25 ml) was treated dropwise with the solution of 2,4,6-trimethylaniline (0.025 mol) also in toluene (20 ml) with constant stirring. The resulting mixture was stirred for about 30 min and set aside for additional 30 min at room temperature for the completion of reaction. The mixture was then treated with dilute hydrochloric acid to remove the unreacted 2,4,6-trimethylaniline. The resultant solid N-(2,4,6-trimethylphenyl)maleamic acid was filtered under suction and washed thoroughly with water to remove the unreacted maleic anhydride and maleic acid. It was recrystallized to constant melting point from ethanol. The purity of the compound was checked by elemental analysis and characterized by its infrared spectra. The single crystals used in X-ray diffraction studies were grown in an ethanol solution by slow evaporation at room temperature.
All H atoms were placed in calculated positions (C–H = 0.93 or 0.96 Å, N–H = 0.86 Å, O–H = 0.90 Å) and refined using a riding model. The Uiso(H) values were set at 1.2Ueq(Caromatic, N, O) or 1.5Ueq(Cmethyl). The C12 methyl group exhibits orientational disorder of the hydrogen atoms. Two sets of H atoms were refined with occupancies of 0.56 (3) and 0.44 (3).
As a part of studying the effect of ring and side chain substitutions on the crystal structures of amide derivatives (Gowda, Foro et al., 2009; Gowda, Tokarčík et al., 2009a,b), the
of N-(2,4,6-trimethylphenyl)-maleamic acid (I) has been determined. The conformations of the N–H and C=O bonds in the amide segment of the structure are anti to each other. Further, the conformation of the amide O atom is anti to the H atom attached to the adjacent C atom, while the carboxyl O atom is syn to the H atom attached to its adjacent C atom (Fig.1). The rare anti conformation of the C=O and O–H bonds of the acid group has been observed, similar to that obsrved in N-(2,6-dimethylphenyl)-maleamic acid (Gowda, Tokarčík et al., 2009a) and N-phenylmaleamic acid (Lo & Ng, 2009), but contrary to the more general syn conformation observed for C=O and O–H bonds of the acid group in N-(2,4,6-trimethylphenyl)succinamic acid (Gowda, Foro et al., 2009). The various modes of interlinking by hydrogen bonds is described elsewhere (Leiserowitz, 1976).The maleamic moiety includes a short intramolecular hydrogen O–H···O bond (Table 1). The C2–C3 bond length of 1.325 (2) Å clearly indicates the double bond character. The dihedral angle between the phenyl ring and the amido group –NHCO– is 58.3 (2)°. The mean plane through all the atoms of the maleamic moiety (N1, C1, C2, C3, C4, O1, O2 and O3) has a r.m.s. value of 0.06 Å, with the most deviating atom N1. In the
the intermolecular N–H···O hydrogen bonds link the molecules into zigzag ribbons propagated in the [0 1 0] direction (Fig. 2).For our sudies on the effect of ring- and side-chain substitutions on the crystal structures of
see: Gowda, Foro et al. (2009); Gowda, Tokarčík et al. (2009a,b); Lo & Ng (2009). For hydrogen bonds in see: Leiserowitz (1976).Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell
CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2002); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and WinGX (Farrugia, 1999).C13H15NO3 | F(000) = 992 |
Mr = 233.26 | Dx = 1.221 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 17006 reflections |
a = 10.8789 (3) Å | θ = 1.9–29.4° |
b = 11.9095 (2) Å | µ = 0.09 mm−1 |
c = 20.1004 (5) Å | T = 295 K |
β = 103.014 (2)° | Block, colourless |
V = 2537.36 (10) Å3 | 0.56 × 0.48 × 0.35 mm |
Z = 8 |
Oxford Diffraction Xcalibur Ruby Gemini diffractometer | 2386 independent reflections |
Graphite monochromator | 2029 reflections with I > 2σ(I) |
Detector resolution: 10.434 pixels mm-1 | Rint = 0.023 |
ω scans | θmax = 25.6°, θmin = 2.1° |
Absorption correction: analytical (CrysAlis PRO; Oxford Diffraction, 2009) | h = −13→13 |
Tmin = 0.933, Tmax = 0.965 | k = −14→14 |
26868 measured reflections | l = −24→24 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.037 | H-atom parameters constrained |
wR(F2) = 0.102 | w = 1/[σ2(Fo2) + (0.0469P)2 + 1.3266P] where P = (Fo2 + 2Fc2)/3 |
S = 1.04 | (Δ/σ)max = 0.001 |
2386 reflections | Δρmax = 0.17 e Å−3 |
159 parameters | Δρmin = −0.12 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0142 (9) |
C13H15NO3 | V = 2537.36 (10) Å3 |
Mr = 233.26 | Z = 8 |
Monoclinic, C2/c | Mo Kα radiation |
a = 10.8789 (3) Å | µ = 0.09 mm−1 |
b = 11.9095 (2) Å | T = 295 K |
c = 20.1004 (5) Å | 0.56 × 0.48 × 0.35 mm |
β = 103.014 (2)° |
Oxford Diffraction Xcalibur Ruby Gemini diffractometer | 2386 independent reflections |
Absorption correction: analytical (CrysAlis PRO; Oxford Diffraction, 2009) | 2029 reflections with I > 2σ(I) |
Tmin = 0.933, Tmax = 0.965 | Rint = 0.023 |
26868 measured reflections |
R[F2 > 2σ(F2)] = 0.037 | 0 restraints |
wR(F2) = 0.102 | H-atom parameters constrained |
S = 1.04 | Δρmax = 0.17 e Å−3 |
2386 reflections | Δρmin = −0.12 e Å−3 |
159 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 | Occ. (<1) | |
C1 | 0.35967 (13) | 0.14861 (11) | 0.17051 (7) | 0.0419 (3) | |
C2 | 0.28501 (17) | 0.17469 (12) | 0.22158 (8) | 0.0576 (4) | |
H2 | 0.2547 | 0.2478 | 0.2206 | 0.069* | |
C3 | 0.25517 (19) | 0.10848 (13) | 0.26854 (8) | 0.0634 (5) | |
H3 | 0.2108 | 0.1445 | 0.2968 | 0.076* | |
C4 | 0.27916 (15) | −0.01212 (12) | 0.28450 (7) | 0.0486 (4) | |
C5 | 0.42558 (11) | 0.23129 (11) | 0.07158 (6) | 0.0379 (3) | |
C6 | 0.51419 (13) | 0.31543 (12) | 0.06931 (7) | 0.0456 (3) | |
C7 | 0.56646 (14) | 0.31987 (13) | 0.01267 (8) | 0.0542 (4) | |
H7 | 0.6248 | 0.376 | 0.0104 | 0.065* | |
C8 | 0.53555 (14) | 0.24425 (13) | −0.04058 (8) | 0.0523 (4) | |
C9 | 0.44899 (14) | 0.16118 (12) | −0.03596 (7) | 0.0490 (4) | |
H9 | 0.4288 | 0.1084 | −0.0708 | 0.059* | |
C10 | 0.39115 (12) | 0.15365 (11) | 0.01878 (7) | 0.0402 (3) | |
C11 | 0.55135 (18) | 0.39999 (15) | 0.12605 (9) | 0.0693 (5) | |
H11A | 0.6218 | 0.4432 | 0.119 | 0.104* | |
H11B | 0.5744 | 0.3615 | 0.169 | 0.104* | |
H11C | 0.4815 | 0.4491 | 0.1263 | 0.104* | |
C12 | 0.5918 (2) | 0.25320 (19) | −0.10259 (10) | 0.0801 (6) | |
H12A | 0.5606 | 0.1931 | −0.1336 | 0.12* | 0.56 (3) |
H12B | 0.6821 | 0.2483 | −0.0887 | 0.12* | 0.56 (3) |
H12C | 0.5686 | 0.3239 | −0.1248 | 0.12* | 0.56 (3) |
H12D | 0.6469 | 0.3171 | −0.0978 | 0.12* | 0.44 (3) |
H12E | 0.5255 | 0.2619 | −0.1428 | 0.12* | 0.44 (3) |
H12F | 0.6389 | 0.1863 | −0.1066 | 0.12* | 0.44 (3) |
C13 | 0.29160 (14) | 0.06565 (12) | 0.01791 (8) | 0.0519 (4) | |
H13A | 0.2615 | 0.0387 | −0.0279 | 0.078* | |
H13B | 0.2227 | 0.0977 | 0.034 | 0.078* | |
H13C | 0.327 | 0.0044 | 0.047 | 0.078* | |
N1 | 0.36385 (11) | 0.23264 (9) | 0.12731 (6) | 0.0424 (3) | |
H1N | 0.3257 | 0.2937 | 0.1335 | 0.051* | |
O1 | 0.41359 (10) | 0.05741 (8) | 0.16796 (5) | 0.0508 (3) | |
O2 | 0.34725 (10) | −0.07126 (8) | 0.25195 (5) | 0.0521 (3) | |
H2A | 0.3763 | −0.0267 | 0.2227 | 0.062* | |
O3 | 0.23146 (13) | −0.05442 (9) | 0.32755 (6) | 0.0693 (4) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0520 (8) | 0.0339 (7) | 0.0424 (7) | 0.0010 (6) | 0.0165 (6) | 0.0039 (5) |
C2 | 0.0900 (12) | 0.0343 (7) | 0.0601 (9) | 0.0118 (7) | 0.0415 (9) | 0.0074 (6) |
C3 | 0.1035 (13) | 0.0422 (8) | 0.0594 (10) | 0.0066 (8) | 0.0497 (10) | 0.0029 (7) |
C4 | 0.0692 (9) | 0.0397 (7) | 0.0379 (7) | −0.0098 (7) | 0.0143 (7) | 0.0026 (6) |
C5 | 0.0387 (7) | 0.0361 (7) | 0.0401 (7) | −0.0004 (5) | 0.0114 (5) | 0.0075 (5) |
C6 | 0.0452 (8) | 0.0414 (7) | 0.0498 (8) | −0.0081 (6) | 0.0098 (6) | 0.0039 (6) |
C7 | 0.0474 (8) | 0.0531 (9) | 0.0658 (10) | −0.0150 (7) | 0.0209 (7) | 0.0091 (7) |
C8 | 0.0515 (8) | 0.0575 (9) | 0.0531 (9) | −0.0009 (7) | 0.0225 (7) | 0.0095 (7) |
C9 | 0.0556 (9) | 0.0491 (8) | 0.0440 (8) | −0.0036 (7) | 0.0149 (6) | −0.0009 (6) |
C10 | 0.0402 (7) | 0.0364 (7) | 0.0441 (7) | −0.0030 (5) | 0.0099 (6) | 0.0052 (5) |
C11 | 0.0781 (12) | 0.0590 (10) | 0.0706 (11) | −0.0267 (9) | 0.0163 (9) | −0.0111 (8) |
C12 | 0.0877 (13) | 0.0929 (15) | 0.0740 (12) | −0.0034 (11) | 0.0480 (11) | 0.0131 (10) |
C13 | 0.0547 (9) | 0.0453 (8) | 0.0546 (9) | −0.0148 (7) | 0.0101 (7) | 0.0023 (6) |
N1 | 0.0534 (7) | 0.0323 (6) | 0.0459 (6) | 0.0032 (5) | 0.0204 (5) | 0.0065 (5) |
O1 | 0.0653 (6) | 0.0409 (5) | 0.0518 (6) | 0.0141 (5) | 0.0252 (5) | 0.0110 (4) |
O2 | 0.0692 (7) | 0.0352 (5) | 0.0546 (6) | −0.0021 (5) | 0.0197 (5) | 0.0072 (4) |
O3 | 0.1074 (10) | 0.0511 (7) | 0.0589 (7) | −0.0122 (6) | 0.0390 (7) | 0.0112 (5) |
C1—O1 | 1.2409 (16) | C9—C10 | 1.3880 (19) |
C1—N1 | 1.3325 (16) | C9—H9 | 0.93 |
C1—C2 | 1.4784 (19) | C10—C13 | 1.5044 (18) |
C2—C3 | 1.325 (2) | C11—H11A | 0.96 |
C2—H2 | 0.93 | C11—H11B | 0.96 |
C3—C4 | 1.482 (2) | C11—H11C | 0.96 |
C3—H3 | 0.93 | C12—H12A | 0.96 |
C4—O3 | 1.2140 (17) | C12—H12B | 0.96 |
C4—O2 | 1.3004 (18) | C12—H12C | 0.96 |
C5—C10 | 1.3937 (19) | C12—H12D | 0.96 |
C5—C6 | 1.3983 (18) | C12—H12E | 0.96 |
C5—N1 | 1.4300 (16) | C12—H12F | 0.96 |
C6—C7 | 1.383 (2) | C13—H13A | 0.96 |
C6—C11 | 1.507 (2) | C13—H13B | 0.96 |
C7—C8 | 1.381 (2) | C13—H13C | 0.96 |
C7—H7 | 0.93 | N1—H1N | 0.86 |
C8—C9 | 1.383 (2) | O2—H2A | 0.9 |
C8—C12 | 1.511 (2) | ||
O1—C1—N1 | 123.00 (12) | C9—C10—C13 | 119.30 (13) |
O1—C1—C2 | 123.46 (12) | C5—C10—C13 | 122.71 (12) |
N1—C1—C2 | 113.55 (12) | C6—C11—H11A | 109.5 |
C3—C2—C1 | 129.10 (14) | C6—C11—H11B | 109.5 |
C3—C2—H2 | 115.5 | H11A—C11—H11B | 109.5 |
C1—C2—H2 | 115.5 | C6—C11—H11C | 109.5 |
C2—C3—C4 | 132.18 (14) | H11A—C11—H11C | 109.5 |
C2—C3—H3 | 113.9 | H11B—C11—H11C | 109.5 |
C4—C3—H3 | 113.9 | C8—C12—H12A | 109.5 |
O3—C4—O2 | 121.14 (14) | C8—C12—H12B | 109.5 |
O3—C4—C3 | 118.28 (14) | C8—C12—H12C | 109.5 |
O2—C4—C3 | 120.56 (12) | C8—C12—H12D | 109.5 |
C10—C5—C6 | 121.31 (12) | C8—C12—H12E | 109.5 |
C10—C5—N1 | 120.72 (11) | H12D—C12—H12E | 109.5 |
C6—C5—N1 | 117.79 (12) | C8—C12—H12F | 109.5 |
C7—C6—C5 | 117.93 (13) | H12D—C12—H12F | 109.5 |
C7—C6—C11 | 120.49 (13) | H12E—C12—H12F | 109.5 |
C5—C6—C11 | 121.58 (13) | C10—C13—H13A | 109.5 |
C8—C7—C6 | 122.64 (13) | C10—C13—H13B | 109.5 |
C8—C7—H7 | 118.7 | H13A—C13—H13B | 109.5 |
C6—C7—H7 | 118.7 | C10—C13—H13C | 109.5 |
C7—C8—C9 | 117.71 (13) | H13A—C13—H13C | 109.5 |
C7—C8—C12 | 121.33 (15) | H13B—C13—H13C | 109.5 |
C9—C8—C12 | 120.95 (15) | C1—N1—C5 | 126.37 (11) |
C8—C9—C10 | 122.43 (14) | C1—N1—H1N | 116.8 |
C8—C9—H9 | 118.8 | C5—N1—H1N | 116.8 |
C10—C9—H9 | 118.8 | C4—O2—H2A | 109.5 |
C9—C10—C5 | 117.95 (12) | ||
O1—C1—C2—C3 | −4.9 (3) | C7—C8—C9—C10 | 1.6 (2) |
N1—C1—C2—C3 | 175.19 (19) | C12—C8—C9—C10 | −176.99 (15) |
C1—C2—C3—C4 | −3.2 (4) | C8—C9—C10—C5 | −2.0 (2) |
C2—C3—C4—O3 | −174.0 (2) | C8—C9—C10—C13 | 175.94 (14) |
C2—C3—C4—O2 | 4.5 (3) | C6—C5—C10—C9 | 0.9 (2) |
C10—C5—C6—C7 | 0.4 (2) | N1—C5—C10—C9 | 176.00 (12) |
N1—C5—C6—C7 | −174.81 (12) | C6—C5—C10—C13 | −176.92 (13) |
C10—C5—C6—C11 | 179.69 (14) | N1—C5—C10—C13 | −1.86 (19) |
N1—C5—C6—C11 | 4.5 (2) | O1—C1—N1—C5 | 1.9 (2) |
C5—C6—C7—C8 | −0.8 (2) | C2—C1—N1—C5 | −178.23 (13) |
C11—C6—C7—C8 | 179.93 (16) | C10—C5—N1—C1 | 59.84 (18) |
C6—C7—C8—C9 | −0.2 (2) | C6—C5—N1—C1 | −124.94 (15) |
C6—C7—C8—C12 | 178.41 (16) |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2A···O1 | 0.90 | 1.61 | 2.5037 (13) | 174 |
N1—H1N···O3i | 0.86 | 2.12 | 2.9587 (15) | 165 |
Symmetry code: (i) −x+1/2, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C13H15NO3 |
Mr | 233.26 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 295 |
a, b, c (Å) | 10.8789 (3), 11.9095 (2), 20.1004 (5) |
β (°) | 103.014 (2) |
V (Å3) | 2537.36 (10) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.56 × 0.48 × 0.35 |
Data collection | |
Diffractometer | Oxford Diffraction Xcalibur Ruby Gemini |
Absorption correction | Analytical (CrysAlis PRO; Oxford Diffraction, 2009) |
Tmin, Tmax | 0.933, 0.965 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 26868, 2386, 2029 |
Rint | 0.023 |
(sin θ/λ)max (Å−1) | 0.608 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.037, 0.102, 1.04 |
No. of reflections | 2386 |
No. of parameters | 159 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.17, −0.12 |
Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2002), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and WinGX (Farrugia, 1999).
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2A···O1 | 0.90 | 1.61 | 2.5037 (13) | 174 |
N1—H1N···O3i | 0.86 | 2.12 | 2.9587 (15) | 165 |
Symmetry code: (i) −x+1/2, y+1/2, −z+1/2. |
Acknowledgements
MT and JK thank the Grant Agency of the Slovak Republic (VEGA 1/0817/08) and Structural Funds, Interreg IIIA, for financial support in purchasing the diffractometer.
References
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As a part of studying the effect of ring and side chain substitutions on the crystal structures of amide derivatives (Gowda, Foro et al., 2009; Gowda, Tokarčík et al., 2009a,b), the crystal structure of N-(2,4,6-trimethylphenyl)-maleamic acid (I) has been determined. The conformations of the N–H and C=O bonds in the amide segment of the structure are anti to each other. Further, the conformation of the amide O atom is anti to the H atom attached to the adjacent C atom, while the carboxyl O atom is syn to the H atom attached to its adjacent C atom (Fig.1). The rare anti conformation of the C=O and O–H bonds of the acid group has been observed, similar to that obsrved in N-(2,6-dimethylphenyl)-maleamic acid (Gowda, Tokarčík et al., 2009a) and N-phenylmaleamic acid (Lo & Ng, 2009), but contrary to the more general syn conformation observed for C=O and O–H bonds of the acid group in N-(2,4,6-trimethylphenyl)succinamic acid (Gowda, Foro et al., 2009). The various modes of interlinking carboxylic acids by hydrogen bonds is described elsewhere (Leiserowitz, 1976).
The maleamic moiety includes a short intramolecular hydrogen O–H···O bond (Table 1). The C2–C3 bond length of 1.325 (2) Å clearly indicates the double bond character. The dihedral angle between the phenyl ring and the amido group –NHCO– is 58.3 (2)°. The mean plane through all the atoms of the maleamic moiety (N1, C1, C2, C3, C4, O1, O2 and O3) has a r.m.s. value of 0.06 Å, with the most deviating atom N1. In the crystal structure, the intermolecular N–H···O hydrogen bonds link the molecules into zigzag ribbons propagated in the [0 1 0] direction (Fig. 2).