organic compounds
2-Methoxy-4-[(4-methylpiperazin-1-yl)iminomethyl]phenol
aCollege of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, Ninxia, People's Republic of China, and bKey Laboratory of Energy Resource and Chemical Engineering, Yinchuan 750021, Ninxia, People's Republic of China
*Correspondence e-mail: huqilin@nxu.edu.cn
The title compound, C13H19N3O2, was obtained by the direct solvent-free reaction of 4-hydroxy-3-methoxybenzaldehyde with 1-amino-4-methylpiperazine. The piperazine ring adopts a chair conformation. In the crystal, strong intermolecular O—H⋯N and weak intermolecular C—H⋯O and C—H⋯N hydrogen bonds help to establish the packing.
Related literature
For the biological properties of piperazine compounds, see: Obniska et al. (2005); Smid et al. (2005). For background and related structures, see: Guo (2004, 2007).
Experimental
Crystal data
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Refinement
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Data collection: SMART (Bruker, 2007); cell SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXL97.
Supporting information
https://doi.org/10.1107/S1600536810051135/im2254sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810051135/im2254Isup2.hkl
The title compound was prepared by the direct solvent-free reaction of 4-hydroxy-3-methoxy-benzaldehyde (1.52 g) with 1-amino-4-methylpiperazine (1.15 g) with stirring at 351 K for 30 min. The resulting product was dissolved in ethanol (10 ml) with heating. The homogeneous solution was allowed to stand at room temperature for 12 h, after which the crystalline product was separated by filtration (yield 2.0 g, 80%). The pure product (0.5 g) was dissolved in hot ethanol (20 ml). Single crystals were obtained from this solution by slow evaporation over a period of 7 d at room temperature.
In the absence of significant
effects Friedel pairs have been merged. All H atoms were positioned geometrically and refined using the riding-model approximation, with C—H = 0.93 or 0.96 Å, O—H = 0.82 Å, N—H = 0.86 Å and Uiso(H) = 1.2Ueq(C, N) or Uiso(H) = 1.5Ueq(methyl C and O).Piperazine and it's derivatives are important targets for drug discovery. For the biological properties of piperazine compounds, see: Obniska et al. (2005); Smid et al. (2005). For background of this study and related structures, see: Guo (2004); Guo (2007).
The title compound, (I), is a hydrazone in which 4-hydroxy-3-methoxy-benzaldehyde has reacted directly with 1-amino-4-methylpiperazine to form a product containing the C=N double bond. The structure of the compound is shown in Fig. 1. The C=N double bond shows an E configuration and is effectively coplanar with the benzene ring [N3–C8–C6–C7=1.6 (5)°]. The piperazine ring exhibits a chair conformation. The bond distances and angles are normal. In the
strong intermolecular N—H···O and weak intermolecular C—H···O and C—H···N hydrogen bonds (see Table 1 for symmetry code) and are responsible for the observed packing motif. A packing diagram for (I) is shown in Fig. 2.For the biological properties of piperazine compounds, see: Obniska et al. (2005); Smid et al. (2005). For background and related structures, see: Guo (2004, 2007).
Data collection: SMART (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).C13H19N3O2 | Dx = 1.213 Mg m−3 |
Mr = 249.31 | Melting point: not measured K |
Orthorhombic, Pna21 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2c -2n | Cell parameters from 1708 reflections |
a = 12.179 (2) Å | θ = 2.0–25.1° |
b = 18.624 (3) Å | µ = 0.08 mm−1 |
c = 6.0187 (10) Å | T = 296 K |
V = 1365.1 (4) Å3 | Club-shaped, colorless |
Z = 4 | 0.25 × 0.25 × 0.10 mm |
F(000) = 536 |
Siemens SMART CCD diffractometer | 1582 independent reflections |
Radiation source: fine-focus sealed tube | 1126 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.043 |
Detector resolution: 9.00 cm pixels mm-1 | θmax = 26.7°, θmin = 2.0° |
ω scans | h = −15→14 |
Absorption correction: multi-scan (SADABS; Bruker, 2002) | k = −23→21 |
Tmin = 0.642, Tmax = 0.745 | l = −7→6 |
7503 measured reflections |
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)] = 0.040 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.077 | w = 1/[σ2(Fo2) + (0.010P)2 + 0.480P] where P = (Fo2 + 2Fc2)/3 |
S = 1.01 | (Δ/σ)max < 0.001 |
1582 reflections | Δρmax = 0.13 e Å−3 |
169 parameters | Δρmin = −0.13 e Å−3 |
1 restraint | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0157 (12) |
C13H19N3O2 | V = 1365.1 (4) Å3 |
Mr = 249.31 | Z = 4 |
Orthorhombic, Pna21 | Mo Kα radiation |
a = 12.179 (2) Å | µ = 0.08 mm−1 |
b = 18.624 (3) Å | T = 296 K |
c = 6.0187 (10) Å | 0.25 × 0.25 × 0.10 mm |
Siemens SMART CCD diffractometer | 1582 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2002) | 1126 reflections with I > 2σ(I) |
Tmin = 0.642, Tmax = 0.745 | Rint = 0.043 |
7503 measured reflections |
R[F2 > 2σ(F2)] = 0.040 | 1 restraint |
wR(F2) = 0.077 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.01 | Δρmax = 0.13 e Å−3 |
1582 reflections | Δρmin = −0.13 e Å−3 |
169 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 | ||
O1 | 0.38591 (18) | 0.68018 (10) | 0.1639 (4) | 0.0597 (7) | |
H1 | 0.440 (3) | 0.6712 (18) | 0.271 (7) | 0.090* | |
O2 | 0.39131 (16) | 0.56755 (10) | 0.4468 (4) | 0.0563 (6) | |
N1 | 0.02060 (18) | 0.33961 (11) | 0.1024 (4) | 0.0441 (6) | |
N2 | −0.05455 (17) | 0.20217 (11) | −0.0440 (5) | 0.0459 (6) | |
N3 | 0.09346 (17) | 0.39555 (11) | 0.1421 (5) | 0.0460 (6) | |
C1 | 0.3972 (3) | 0.50737 (15) | 0.5919 (6) | 0.0621 (9) | |
H1A | 0.3291 | 0.5025 | 0.6707 | 0.093* | |
H1B | 0.4560 | 0.5143 | 0.6961 | 0.093* | |
H1C | 0.4107 | 0.4647 | 0.5068 | 0.093* | |
C2 | 0.3147 (2) | 0.56473 (14) | 0.2784 (5) | 0.0406 (7) | |
C3 | 0.3161 (2) | 0.62428 (13) | 0.1367 (5) | 0.0433 (7) | |
C4 | 0.2429 (2) | 0.62631 (14) | −0.0381 (6) | 0.0500 (7) | |
H4 | 0.2428 | 0.6656 | −0.1336 | 0.060* | |
C5 | 0.1695 (2) | 0.57068 (14) | −0.0731 (6) | 0.0491 (8) | |
H5 | 0.1202 | 0.5733 | −0.1908 | 0.059* | |
C6 | 0.1687 (2) | 0.51122 (14) | 0.0650 (5) | 0.0429 (7) | |
C7 | 0.2418 (2) | 0.50933 (14) | 0.2442 (5) | 0.0439 (7) | |
H7 | 0.2412 | 0.4704 | 0.3408 | 0.053* | |
C8 | 0.0937 (2) | 0.45134 (14) | 0.0184 (6) | 0.0478 (8) | |
H8A | 0.0471 | 0.4551 | −0.1155 | 0.057* | |
C9 | 0.0658 (2) | 0.27338 (13) | 0.1924 (6) | 0.0517 (8) | |
H9A | 0.0887 | 0.2812 | 0.3449 | 0.062* | |
H9B | 0.1299 | 0.2594 | 0.1070 | 0.062* | |
C10 | −0.0186 (2) | 0.21406 (15) | 0.1845 (6) | 0.0518 (8) | |
H10A | 0.0129 | 0.1702 | 0.2435 | 0.062* | |
H10B | −0.0812 | 0.2270 | 0.2759 | 0.062* | |
C11 | −0.1364 (2) | 0.14440 (14) | −0.0515 (7) | 0.0655 (10) | |
H11A | −0.1034 | 0.1003 | −0.0032 | 0.098* | |
H11B | −0.1628 | 0.1390 | −0.2009 | 0.098* | |
H11C | −0.1967 | 0.1562 | 0.0446 | 0.098* | |
C12 | −0.1020 (2) | 0.26857 (13) | −0.1319 (6) | 0.0524 (9) | |
H12A | −0.1667 | 0.2810 | −0.0461 | 0.063* | |
H12B | −0.1247 | 0.2609 | −0.2845 | 0.063* | |
C13 | −0.0210 (2) | 0.33023 (15) | −0.1233 (6) | 0.0500 (9) | |
H13A | 0.0398 | 0.3206 | −0.2233 | 0.060* | |
H13B | −0.0567 | 0.3741 | −0.1718 | 0.060* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0704 (15) | 0.0501 (12) | 0.0588 (16) | −0.0206 (11) | −0.0153 (13) | 0.0126 (12) |
O2 | 0.0664 (13) | 0.0492 (11) | 0.0535 (14) | −0.0121 (10) | −0.0184 (14) | 0.0125 (12) |
N1 | 0.0432 (13) | 0.0371 (12) | 0.0519 (17) | −0.0026 (10) | −0.0032 (13) | −0.0023 (12) |
N2 | 0.0443 (12) | 0.0383 (12) | 0.0550 (17) | −0.0042 (10) | 0.0015 (14) | −0.0058 (14) |
N3 | 0.0453 (13) | 0.0377 (12) | 0.0549 (17) | −0.0026 (11) | 0.0025 (13) | −0.0054 (13) |
C1 | 0.075 (2) | 0.0572 (18) | 0.054 (2) | 0.0014 (16) | −0.013 (2) | 0.0147 (18) |
C2 | 0.0438 (16) | 0.0369 (15) | 0.0410 (17) | 0.0015 (12) | −0.0031 (14) | 0.0023 (14) |
C3 | 0.0462 (16) | 0.0365 (15) | 0.0473 (19) | −0.0047 (12) | −0.0008 (15) | 0.0041 (16) |
C4 | 0.0592 (18) | 0.0406 (15) | 0.0502 (19) | −0.0013 (14) | −0.0062 (18) | 0.0078 (17) |
C5 | 0.0479 (16) | 0.0477 (16) | 0.052 (2) | 0.0020 (14) | −0.0128 (17) | 0.0035 (16) |
C6 | 0.0377 (15) | 0.0378 (14) | 0.053 (2) | 0.0014 (12) | −0.0004 (14) | −0.0016 (14) |
C7 | 0.0460 (16) | 0.0352 (14) | 0.051 (2) | −0.0021 (13) | −0.0013 (16) | 0.0065 (14) |
C8 | 0.0420 (16) | 0.0428 (15) | 0.059 (2) | 0.0007 (13) | −0.0032 (15) | −0.0021 (15) |
C9 | 0.0599 (18) | 0.0465 (16) | 0.049 (2) | −0.0022 (14) | −0.0068 (16) | 0.0026 (16) |
C10 | 0.0581 (19) | 0.0421 (16) | 0.055 (2) | −0.0050 (14) | 0.0064 (17) | 0.0006 (16) |
C11 | 0.0586 (19) | 0.0456 (16) | 0.092 (3) | −0.0088 (14) | 0.001 (2) | −0.008 (2) |
C12 | 0.0487 (17) | 0.0434 (16) | 0.065 (2) | 0.0024 (14) | −0.0094 (15) | −0.0078 (16) |
C13 | 0.0531 (18) | 0.0421 (17) | 0.055 (2) | 0.0010 (14) | −0.0105 (16) | 0.0010 (15) |
O1—C3 | 1.354 (3) | C5—C6 | 1.385 (4) |
O1—H1 | 0.94 (4) | C5—H5 | 0.9300 |
O2—C2 | 1.378 (3) | C6—C7 | 1.399 (4) |
O2—C1 | 1.423 (3) | C6—C8 | 1.468 (4) |
N1—N3 | 1.389 (3) | C7—H7 | 0.9300 |
N1—C9 | 1.456 (3) | C8—H8A | 0.9884 |
N1—C13 | 1.460 (4) | C9—C10 | 1.510 (4) |
N2—C10 | 1.460 (4) | C9—H9A | 0.9700 |
N2—C12 | 1.464 (3) | C9—H9B | 0.9700 |
N2—C11 | 1.468 (3) | C10—H10A | 0.9700 |
N3—C8 | 1.278 (3) | C10—H10B | 0.9700 |
C1—H1A | 0.9600 | C11—H11A | 0.9600 |
C1—H1B | 0.9600 | C11—H11B | 0.9600 |
C1—H1C | 0.9600 | C11—H11C | 0.9600 |
C2—C7 | 1.377 (4) | C12—C13 | 1.515 (4) |
C2—C3 | 1.399 (4) | C12—H12A | 0.9700 |
C3—C4 | 1.380 (4) | C12—H12B | 0.9700 |
C4—C5 | 1.384 (3) | C13—H13A | 0.9700 |
C4—H4 | 0.9300 | C13—H13B | 0.9700 |
C3—O1—H1 | 113 (2) | N3—C8—C6 | 120.5 (3) |
C2—O2—C1 | 117.1 (2) | N3—C8—H8A | 122.1 |
N3—N1—C9 | 109.2 (2) | C6—C8—H8A | 117.3 |
N3—N1—C13 | 118.1 (2) | N1—C9—C10 | 110.5 (2) |
C9—N1—C13 | 112.1 (2) | N1—C9—H9A | 109.5 |
C10—N2—C12 | 109.3 (2) | C10—C9—H9A | 109.5 |
C10—N2—C11 | 110.1 (3) | N1—C9—H9B | 109.5 |
C12—N2—C11 | 109.9 (2) | C10—C9—H9B | 109.5 |
C8—N3—N1 | 120.7 (2) | H9A—C9—H9B | 108.1 |
O2—C1—H1A | 109.5 | N2—C10—C9 | 110.2 (3) |
O2—C1—H1B | 109.5 | N2—C10—H10A | 109.6 |
H1A—C1—H1B | 109.5 | C9—C10—H10A | 109.6 |
O2—C1—H1C | 109.5 | N2—C10—H10B | 109.6 |
H1A—C1—H1C | 109.5 | C9—C10—H10B | 109.6 |
H1B—C1—H1C | 109.5 | H10A—C10—H10B | 108.1 |
C7—C2—O2 | 125.1 (3) | N2—C11—H11A | 109.5 |
C7—C2—C3 | 120.7 (3) | N2—C11—H11B | 109.5 |
O2—C2—C3 | 114.2 (2) | H11A—C11—H11B | 109.5 |
O1—C3—C4 | 118.5 (3) | N2—C11—H11C | 109.5 |
O1—C3—C2 | 122.9 (3) | H11A—C11—H11C | 109.5 |
C4—C3—C2 | 118.6 (2) | H11B—C11—H11C | 109.5 |
C3—C4—C5 | 120.9 (3) | N2—C12—C13 | 111.8 (2) |
C3—C4—H4 | 119.6 | N2—C12—H12A | 109.3 |
C5—C4—H4 | 119.6 | C13—C12—H12A | 109.3 |
C4—C5—C6 | 120.8 (3) | N2—C12—H12B | 109.3 |
C4—C5—H5 | 119.6 | C13—C12—H12B | 109.3 |
C6—C5—H5 | 119.6 | H12A—C12—H12B | 107.9 |
C5—C6—C7 | 118.6 (3) | N1—C13—C12 | 110.4 (3) |
C5—C6—C8 | 119.9 (3) | N1—C13—H13A | 109.6 |
C7—C6—C8 | 121.6 (3) | C12—C13—H13A | 109.6 |
C2—C7—C6 | 120.5 (3) | N1—C13—H13B | 109.6 |
C2—C7—H7 | 119.8 | C12—C13—H13B | 109.6 |
C6—C7—H7 | 119.8 | H13A—C13—H13B | 108.1 |
C9—N1—N3—C8 | 155.1 (3) | C5—C6—C7—C2 | −1.6 (4) |
C13—N1—N3—C8 | 25.5 (4) | C8—C6—C7—C2 | 177.0 (3) |
C1—O2—C2—C7 | 2.0 (4) | N1—N3—C8—C6 | 178.2 (2) |
C1—O2—C2—C3 | −177.6 (3) | C5—C6—C8—N3 | 178.7 (3) |
C7—C2—C3—O1 | 179.7 (3) | C7—C6—C8—N3 | 0.1 (4) |
O2—C2—C3—O1 | −0.7 (4) | N3—N1—C9—C10 | 171.1 (3) |
C7—C2—C3—C4 | 0.0 (4) | C13—N1—C9—C10 | −56.0 (3) |
O2—C2—C3—C4 | 179.6 (3) | C12—N2—C10—C9 | −59.3 (3) |
O1—C3—C4—C5 | −179.8 (3) | C11—N2—C10—C9 | 179.9 (2) |
C2—C3—C4—C5 | −0.1 (4) | N1—C9—C10—N2 | 58.7 (3) |
C3—C4—C5—C6 | −0.7 (5) | C10—N2—C12—C13 | 58.0 (3) |
C4—C5—C6—C7 | 1.5 (4) | C11—N2—C12—C13 | 178.9 (3) |
C4—C5—C6—C8 | −177.1 (3) | N3—N1—C13—C12 | −177.9 (2) |
O2—C2—C7—C6 | −178.7 (3) | C9—N1—C13—C12 | 53.7 (3) |
C3—C2—C7—C6 | 0.8 (4) | N2—C12—C13—N1 | −54.9 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N2i | 0.94 (4) | 1.88 (4) | 2.734 (3) | 151 (3) |
C11—H11A···O2ii | 0.96 | 2.67 | 3.311 (4) | 125 |
C5—H5···N1iii | 0.93 | 2.67 | 3.460 (4) | 143 |
Symmetry codes: (i) −x+1/2, y+1/2, z+1/2; (ii) −x+1/2, y−1/2, z−1/2; (iii) −x, −y+1, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C13H19N3O2 |
Mr | 249.31 |
Crystal system, space group | Orthorhombic, Pna21 |
Temperature (K) | 296 |
a, b, c (Å) | 12.179 (2), 18.624 (3), 6.0187 (10) |
V (Å3) | 1365.1 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.25 × 0.25 × 0.10 |
Data collection | |
Diffractometer | Siemens SMART CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2002) |
Tmin, Tmax | 0.642, 0.745 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7503, 1582, 1126 |
Rint | 0.043 |
(sin θ/λ)max (Å−1) | 0.632 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.040, 0.077, 1.01 |
No. of reflections | 1582 |
No. of parameters | 169 |
No. of restraints | 1 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.13, −0.13 |
Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999).
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N2i | 0.94 (4) | 1.88 (4) | 2.734 (3) | 151 (3) |
C11—H11A···O2ii | 0.96 | 2.67 | 3.311 (4) | 124.5 |
C5—H5···N1iii | 0.93 | 2.67 | 3.460 (4) | 143.3 |
Symmetry codes: (i) −x+1/2, y+1/2, z+1/2; (ii) −x+1/2, y−1/2, z−1/2; (iii) −x, −y+1, z−1/2. |
Acknowledgements
We thank the Instrumental Analysis Center of Northwest University for the data collection on the CCD facility.
References
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This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
Piperazine and it's derivatives are important targets for drug discovery. For the biological properties of piperazine compounds, see: Obniska et al. (2005); Smid et al. (2005). For background of this study and related structures, see: Guo (2004); Guo (2007).
The title compound, (I), is a hydrazone in which 4-hydroxy-3-methoxy-benzaldehyde has reacted directly with 1-amino-4-methylpiperazine to form a product containing the C=N double bond. The structure of the compound is shown in Fig. 1. The C=N double bond shows an E configuration and is effectively coplanar with the benzene ring [N3–C8–C6–C7=1.6 (5)°]. The piperazine ring exhibits a chair conformation. The bond distances and angles are normal. In the crystal structure, strong intermolecular N—H···O and weak intermolecular C—H···O and C—H···N hydrogen bonds (see Table 1 for symmetry code) and van der Waals forces are responsible for the observed packing motif. A packing diagram for (I) is shown in Fig. 2.