organic compounds
N-[(9-Ethyl-9H-carbazol-3-yl)methylidene]-3,4-dimethylisoxazol-5-amine
aChemistry Department, Faculty of Science, King Abdul Aziz University, PO Box 80203, Jeddah 21589, Saudi Arabia, and bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: seikweng@um.edu.my
The azomethine double bond in the title Schiff base, C20H19N3O, has an E configuration. The 13-membered carbazolyl fused ring system [r.m.s. deviation = 0.023 (9) Å] is nearly coplanar with the five-membered pyrazole ring [r.m.s. deviation = 0.003 (4) Å]; the dihedral angle between the two systems is 10.8 (2)°. The crystal studied was a non-merohedral twin having a 35% minor component.
Related literature
For the synthesis and spectroscopic characterization of the title compound, see: Asiri et al. (2010). For the treatment of non-merohedral twins, see: Spek (2009).
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2010).
Supporting information
https://doi.org/10.1107/S1600536810027686/rk2213sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810027686/rk2213Isup2.hkl
Carbon-bound H-atoms were placed in calculated positions [C—H 0.95 to 0.98Å with Uiso(H) 1.2 to 1.5Ueq(C)] and were included in the
in the riding model approximation.The crystal studied is a non-merohedral twin; PLATON (Spek, 2009) gave the
as (-1 0 0, 0 -1 0, 0.260 0 -1). The de-twinning option lowered the R index from 17% to a more acceptable level. However, the affected the so that the thermal ellipsoids, particularly those of the heterocyclic ring, were somewhat large.We have recently reported the synthesis and characterization of this Schiff base (Asiri et al., 2010). The azomethine double-bond of the Schiff base (Scheme, Fig. 1) has an E-configuration. The 13-membered carbazolyl fused-ring (r.m.s. deviation 0.023 (9)Å) is nearly coplanar with 5-membered pyrazolyl ring (r.m.s. deviation 0.003 (4)Å) (dihedral angle between the two systems 10.8 (2)°).
For the synthesis and spectroscopic characterization of this Schiff base, see: Asiri et al. (2010). For the treatment of non-merohedral twins, see: Spek (2009).
Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2010).C20H19N3O | F(000) = 672 |
Mr = 317.38 | Dx = 1.313 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 3958 reflections |
a = 8.0575 (9) Å | θ = 2.5–27.4° |
b = 13.4483 (15) Å | µ = 0.08 mm−1 |
c = 14.8488 (16) Å | T = 100 K |
β = 94.049 (2)° | Prism, yellow |
V = 1605.0 (3) Å3 | 0.20 × 0.15 × 0.05 mm |
Z = 4 |
Bruker SMART APEX diffractometer | 2286 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.057 |
Graphite monochromator | θmax = 25.0°, θmin = 2.1° |
ω scans | h = −9→8 |
11993 measured reflections | k = −15→15 |
2811 independent reflections | l = −17→17 |
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)] = 0.089 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.262 | H-atom parameters constrained |
S = 1.11 | w = 1/[σ2(Fo2) + (0.1086P)2 + 4.6936P] where P = (Fo2 + 2Fc2)/3 |
2811 reflections | (Δ/σ)max = 0.001 |
221 parameters | Δρmax = 0.55 e Å−3 |
0 restraints | Δρmin = −0.54 e Å−3 |
C20H19N3O | V = 1605.0 (3) Å3 |
Mr = 317.38 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 8.0575 (9) Å | µ = 0.08 mm−1 |
b = 13.4483 (15) Å | T = 100 K |
c = 14.8488 (16) Å | 0.20 × 0.15 × 0.05 mm |
β = 94.049 (2)° |
Bruker SMART APEX diffractometer | 2286 reflections with I > 2σ(I) |
11993 measured reflections | Rint = 0.057 |
2811 independent reflections |
R[F2 > 2σ(F2)] = 0.089 | 0 restraints |
wR(F2) = 0.262 | H-atom parameters constrained |
S = 1.11 | Δρmax = 0.55 e Å−3 |
2811 reflections | Δρmin = −0.54 e Å−3 |
221 parameters |
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 > 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 | 0.2910 (4) | 0.3151 (2) | 0.1571 (2) | 0.0238 (8) | |
N1 | 1.1980 (5) | 0.1389 (3) | 0.4076 (3) | 0.0219 (9) | |
N2 | 0.4716 (5) | 0.1815 (3) | 0.2053 (3) | 0.0216 (9) | |
N3 | 0.1279 (5) | 0.3252 (3) | 0.1158 (3) | 0.0253 (9) | |
C1 | 1.1728 (6) | 0.3018 (3) | 0.3684 (3) | 0.0187 (10) | |
C2 | 1.2291 (6) | 0.3999 (3) | 0.3616 (3) | 0.0215 (10) | |
H2 | 1.1602 | 0.4489 | 0.3320 | 0.026* | |
C3 | 1.3860 (6) | 0.4244 (3) | 0.3984 (3) | 0.0257 (11) | |
H3 | 1.4247 | 0.4909 | 0.3947 | 0.031* | |
C4 | 1.4879 (6) | 0.3522 (4) | 0.4411 (3) | 0.0257 (11) | |
H4 | 1.5947 | 0.3708 | 0.4667 | 0.031* | |
C5 | 1.4375 (6) | 0.2540 (4) | 0.4472 (3) | 0.0248 (11) | |
H5 | 1.5084 | 0.2049 | 0.4753 | 0.030* | |
C6 | 1.2794 (6) | 0.2302 (3) | 0.4105 (3) | 0.0185 (10) | |
C7 | 1.2634 (6) | 0.0460 (3) | 0.4467 (3) | 0.0239 (11) | |
H7A | 1.1712 | 0.0081 | 0.4710 | 0.029* | |
H7B | 1.3453 | 0.0614 | 0.4976 | 0.029* | |
C8 | 1.3456 (7) | −0.0178 (4) | 0.3792 (4) | 0.0336 (13) | |
H8A | 1.3818 | −0.0805 | 0.4078 | 0.050* | |
H8B | 1.4423 | 0.0174 | 0.3583 | 0.050* | |
H8C | 1.2662 | −0.0315 | 0.3277 | 0.050* | |
C9 | 1.0436 (6) | 0.1505 (3) | 0.3641 (3) | 0.0175 (10) | |
C10 | 1.0204 (6) | 0.2514 (3) | 0.3393 (3) | 0.0180 (10) | |
C11 | 0.8678 (6) | 0.2813 (3) | 0.2978 (3) | 0.0193 (10) | |
H11 | 0.8495 | 0.3491 | 0.2821 | 0.023* | |
C12 | 0.7420 (6) | 0.2112 (3) | 0.2796 (3) | 0.0212 (10) | |
C13 | 0.7718 (6) | 0.1102 (3) | 0.3024 (3) | 0.0212 (10) | |
H13 | 0.6869 | 0.0627 | 0.2875 | 0.025* | |
C14 | 0.9185 (6) | 0.0784 (3) | 0.3453 (3) | 0.0228 (11) | |
H14 | 0.9354 | 0.0107 | 0.3616 | 0.027* | |
C15 | 0.5842 (6) | 0.2432 (3) | 0.2365 (3) | 0.0205 (10) | |
H15 | 0.5625 | 0.3124 | 0.2311 | 0.025* | |
C16 | 0.3229 (6) | 0.2162 (3) | 0.1664 (3) | 0.0186 (10) | |
C17 | 0.1911 (6) | 0.1619 (3) | 0.1324 (3) | 0.0207 (10) | |
C18 | 0.0728 (6) | 0.2352 (3) | 0.1022 (3) | 0.0197 (10) | |
C19 | 0.1746 (6) | 0.0520 (3) | 0.1276 (3) | 0.0253 (11) | |
H19A | 0.2802 | 0.0211 | 0.1493 | 0.038* | |
H19B | 0.1463 | 0.0320 | 0.0650 | 0.038* | |
H19C | 0.0866 | 0.0304 | 0.1655 | 0.038* | |
C20 | −0.0982 (6) | 0.2179 (4) | 0.0589 (3) | 0.0280 (11) | |
H20A | −0.1665 | 0.1847 | 0.1020 | 0.042* | |
H20B | −0.0911 | 0.1758 | 0.0054 | 0.042* | |
H20C | −0.1488 | 0.2818 | 0.0410 | 0.042* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0252 (18) | 0.0164 (16) | 0.0296 (18) | −0.0002 (14) | 0.0004 (14) | 0.0000 (13) |
N1 | 0.026 (2) | 0.0186 (19) | 0.021 (2) | 0.0010 (17) | 0.0022 (17) | 0.0028 (15) |
N2 | 0.023 (2) | 0.0176 (19) | 0.024 (2) | −0.0013 (17) | 0.0046 (17) | 0.0003 (15) |
N3 | 0.024 (2) | 0.024 (2) | 0.028 (2) | 0.0035 (18) | 0.0010 (18) | 0.0026 (17) |
C1 | 0.022 (2) | 0.019 (2) | 0.015 (2) | −0.0006 (19) | 0.0041 (18) | −0.0030 (17) |
C2 | 0.021 (2) | 0.016 (2) | 0.027 (2) | 0.0013 (19) | 0.002 (2) | −0.0006 (18) |
C3 | 0.024 (3) | 0.019 (2) | 0.034 (3) | −0.003 (2) | 0.004 (2) | −0.003 (2) |
C4 | 0.021 (2) | 0.031 (3) | 0.024 (2) | −0.001 (2) | 0.001 (2) | −0.004 (2) |
C5 | 0.029 (3) | 0.027 (2) | 0.019 (2) | 0.009 (2) | 0.001 (2) | 0.0007 (19) |
C6 | 0.021 (2) | 0.018 (2) | 0.017 (2) | 0.0017 (19) | 0.0020 (18) | −0.0010 (17) |
C7 | 0.031 (3) | 0.016 (2) | 0.025 (2) | 0.003 (2) | −0.002 (2) | 0.0036 (18) |
C8 | 0.037 (3) | 0.027 (3) | 0.037 (3) | 0.009 (2) | 0.000 (2) | 0.002 (2) |
C9 | 0.021 (2) | 0.016 (2) | 0.015 (2) | 0.0030 (18) | 0.0046 (19) | 0.0001 (17) |
C10 | 0.024 (3) | 0.014 (2) | 0.016 (2) | −0.0009 (18) | 0.0040 (19) | −0.0010 (16) |
C11 | 0.023 (3) | 0.017 (2) | 0.018 (2) | 0.0014 (19) | 0.0032 (19) | −0.0007 (17) |
C12 | 0.024 (3) | 0.021 (2) | 0.019 (2) | −0.003 (2) | 0.0043 (19) | −0.0026 (18) |
C13 | 0.025 (3) | 0.017 (2) | 0.022 (2) | −0.0061 (19) | 0.005 (2) | −0.0020 (18) |
C14 | 0.030 (3) | 0.013 (2) | 0.025 (2) | −0.001 (2) | 0.005 (2) | 0.0007 (18) |
C15 | 0.021 (2) | 0.017 (2) | 0.024 (2) | −0.0023 (19) | 0.005 (2) | −0.0019 (18) |
C16 | 0.023 (2) | 0.014 (2) | 0.019 (2) | 0.0001 (18) | 0.0054 (19) | 0.0019 (17) |
C17 | 0.021 (2) | 0.019 (2) | 0.022 (2) | −0.0016 (19) | 0.0039 (19) | −0.0006 (18) |
C18 | 0.021 (2) | 0.020 (2) | 0.018 (2) | −0.0012 (19) | 0.0040 (19) | 0.0003 (18) |
C19 | 0.024 (3) | 0.016 (2) | 0.036 (3) | −0.002 (2) | −0.003 (2) | 0.0011 (19) |
C20 | 0.025 (3) | 0.033 (3) | 0.026 (3) | 0.000 (2) | 0.000 (2) | 0.001 (2) |
O1—C16 | 1.360 (5) | C8—H8B | 0.9800 |
O1—N3 | 1.417 (5) | C8—H8C | 0.9800 |
N1—C9 | 1.369 (6) | C9—C14 | 1.412 (6) |
N1—C6 | 1.391 (6) | C9—C10 | 1.416 (6) |
N1—C7 | 1.461 (6) | C10—C11 | 1.395 (6) |
N2—C15 | 1.291 (6) | C11—C12 | 1.397 (6) |
N2—C16 | 1.375 (6) | C11—H11 | 0.9500 |
N3—C18 | 1.300 (6) | C12—C13 | 1.416 (6) |
C1—C2 | 1.400 (6) | C12—C15 | 1.448 (7) |
C1—C6 | 1.407 (6) | C13—C14 | 1.371 (7) |
C1—C10 | 1.443 (6) | C13—H13 | 0.9500 |
C2—C3 | 1.381 (7) | C14—H14 | 0.9500 |
C2—H2 | 0.9500 | C15—H15 | 0.9500 |
C3—C4 | 1.395 (7) | C16—C17 | 1.357 (6) |
C3—H3 | 0.9500 | C17—C18 | 1.422 (6) |
C4—C5 | 1.386 (7) | C17—C19 | 1.485 (6) |
C4—H4 | 0.9500 | C18—C20 | 1.496 (7) |
C5—C6 | 1.387 (7) | C19—H19A | 0.9800 |
C5—H5 | 0.9500 | C19—H19B | 0.9800 |
C7—C8 | 1.507 (7) | C19—H19C | 0.9800 |
C7—H7A | 0.9900 | C20—H20A | 0.9800 |
C7—H7B | 0.9900 | C20—H20B | 0.9800 |
C8—H8A | 0.9800 | C20—H20C | 0.9800 |
C16—O1—N3 | 107.5 (3) | C11—C10—C9 | 119.2 (4) |
C9—N1—C6 | 109.0 (4) | C11—C10—C1 | 134.6 (4) |
C9—N1—C7 | 125.1 (4) | C9—C10—C1 | 106.2 (4) |
C6—N1—C7 | 125.9 (4) | C10—C11—C12 | 119.7 (4) |
C15—N2—C16 | 120.1 (4) | C10—C11—H11 | 120.1 |
C18—N3—O1 | 105.9 (4) | C12—C11—H11 | 120.1 |
C2—C1—C6 | 119.1 (4) | C11—C12—C13 | 119.5 (4) |
C2—C1—C10 | 134.0 (4) | C11—C12—C15 | 119.2 (4) |
C6—C1—C10 | 107.0 (4) | C13—C12—C15 | 121.3 (4) |
C3—C2—C1 | 119.2 (4) | C14—C13—C12 | 122.4 (4) |
C3—C2—H2 | 120.4 | C14—C13—H13 | 118.8 |
C1—C2—H2 | 120.4 | C12—C13—H13 | 118.8 |
C2—C3—C4 | 120.4 (4) | C13—C14—C9 | 117.3 (4) |
C2—C3—H3 | 119.8 | C13—C14—H14 | 121.4 |
C4—C3—H3 | 119.8 | C9—C14—H14 | 121.4 |
C5—C4—C3 | 121.8 (5) | N2—C15—C12 | 122.7 (4) |
C5—C4—H4 | 119.1 | N2—C15—H15 | 118.6 |
C3—C4—H4 | 119.1 | C12—C15—H15 | 118.6 |
C4—C5—C6 | 117.3 (4) | C17—C16—O1 | 110.6 (4) |
C4—C5—H5 | 121.3 | C17—C16—N2 | 127.6 (4) |
C6—C5—H5 | 121.3 | O1—C16—N2 | 121.9 (4) |
C5—C6—N1 | 129.3 (4) | C16—C17—C18 | 103.5 (4) |
C5—C6—C1 | 122.1 (4) | C16—C17—C19 | 128.2 (4) |
N1—C6—C1 | 108.6 (4) | C18—C17—C19 | 128.3 (4) |
N1—C7—C8 | 112.7 (4) | N3—C18—C17 | 112.5 (4) |
N1—C7—H7A | 109.1 | N3—C18—C20 | 120.4 (4) |
C8—C7—H7A | 109.1 | C17—C18—C20 | 127.2 (4) |
N1—C7—H7B | 109.1 | C17—C19—H19A | 109.5 |
C8—C7—H7B | 109.1 | C17—C19—H19B | 109.5 |
H7A—C7—H7B | 107.8 | H19A—C19—H19B | 109.5 |
C7—C8—H8A | 109.5 | C17—C19—H19C | 109.5 |
C7—C8—H8B | 109.5 | H19A—C19—H19C | 109.5 |
H8A—C8—H8B | 109.5 | H19B—C19—H19C | 109.5 |
C7—C8—H8C | 109.5 | C18—C20—H20A | 109.5 |
H8A—C8—H8C | 109.5 | C18—C20—H20B | 109.5 |
H8B—C8—H8C | 109.5 | H20A—C20—H20B | 109.5 |
N1—C9—C14 | 128.9 (4) | C18—C20—H20C | 109.5 |
N1—C9—C10 | 109.3 (4) | H20A—C20—H20C | 109.5 |
C14—C9—C10 | 121.8 (4) | H20B—C20—H20C | 109.5 |
C16—O1—N3—C18 | −0.6 (5) | C2—C1—C10—C9 | 178.0 (5) |
C6—C1—C2—C3 | −1.7 (6) | C6—C1—C10—C9 | −1.0 (5) |
C10—C1—C2—C3 | 179.5 (5) | C9—C10—C11—C12 | −1.5 (6) |
C1—C2—C3—C4 | 0.6 (7) | C1—C10—C11—C12 | −179.1 (5) |
C2—C3—C4—C5 | 0.9 (7) | C10—C11—C12—C13 | −0.8 (6) |
C3—C4—C5—C6 | −1.2 (7) | C10—C11—C12—C15 | 180.0 (4) |
C4—C5—C6—N1 | −179.6 (4) | C11—C12—C13—C14 | 2.5 (7) |
C4—C5—C6—C1 | 0.1 (7) | C15—C12—C13—C14 | −178.3 (4) |
C9—N1—C6—C5 | −179.6 (4) | C12—C13—C14—C9 | −1.8 (7) |
C7—N1—C6—C5 | 2.0 (7) | N1—C9—C14—C13 | 178.3 (4) |
C9—N1—C6—C1 | 0.6 (5) | C10—C9—C14—C13 | −0.6 (6) |
C7—N1—C6—C1 | −177.8 (4) | C16—N2—C15—C12 | 178.9 (4) |
C2—C1—C6—C5 | 1.3 (6) | C11—C12—C15—N2 | 169.3 (4) |
C10—C1—C6—C5 | −179.6 (4) | C13—C12—C15—N2 | −9.9 (7) |
C2—C1—C6—N1 | −178.9 (4) | N3—O1—C16—C17 | 0.9 (5) |
C10—C1—C6—N1 | 0.2 (5) | N3—O1—C16—N2 | −179.4 (4) |
C9—N1—C7—C8 | 86.7 (6) | C15—N2—C16—C17 | −178.4 (4) |
C6—N1—C7—C8 | −95.2 (5) | C15—N2—C16—O1 | 2.0 (6) |
C6—N1—C9—C14 | 179.8 (4) | O1—C16—C17—C18 | −0.9 (5) |
C7—N1—C9—C14 | −1.9 (7) | N2—C16—C17—C18 | 179.5 (4) |
C6—N1—C9—C10 | −1.2 (5) | O1—C16—C17—C19 | 178.9 (4) |
C7—N1—C9—C10 | 177.1 (4) | N2—C16—C17—C19 | −0.7 (8) |
N1—C9—C10—C11 | −176.9 (4) | O1—N3—C18—C17 | 0.1 (5) |
C14—C9—C10—C11 | 2.2 (6) | O1—N3—C18—C20 | −179.9 (4) |
N1—C9—C10—C1 | 1.4 (5) | C16—C17—C18—N3 | 0.5 (5) |
C14—C9—C10—C1 | −179.6 (4) | C19—C17—C18—N3 | −179.3 (5) |
C2—C1—C10—C11 | −4.2 (9) | C16—C17—C18—C20 | −179.5 (4) |
C6—C1—C10—C11 | 176.8 (5) | C19—C17—C18—C20 | 0.7 (8) |
Experimental details
Crystal data | |
Chemical formula | C20H19N3O |
Mr | 317.38 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 100 |
a, b, c (Å) | 8.0575 (9), 13.4483 (15), 14.8488 (16) |
β (°) | 94.049 (2) |
V (Å3) | 1605.0 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.20 × 0.15 × 0.05 |
Data collection | |
Diffractometer | Bruker SMART APEX diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 11993, 2811, 2286 |
Rint | 0.057 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.089, 0.262, 1.11 |
No. of reflections | 2811 |
No. of parameters | 221 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.55, −0.54 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2010).
Acknowledgements
We thank King Abdul Aziz University and the University of Malaya for supporting this study.
References
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We have recently reported the synthesis and characterization of this Schiff base (Asiri et al., 2010). The azomethine double-bond of the Schiff base (Scheme, Fig. 1) has an E-configuration. The 13-membered carbazolyl fused-ring (r.m.s. deviation 0.023 (9)Å) is nearly coplanar with 5-membered pyrazolyl ring (r.m.s. deviation 0.003 (4)Å) (dihedral angle between the two systems 10.8 (2)°).