organic compounds
(+)-(S)-N-[(1-Benzothiophen-2-yl)methylidene]-1-(naphthalen-1-yl)ethylamine
aLab. Síntesis de Complejos, Facultad de Ciencias Químicas, Benemérita, Universidad Autónoma de Puebla, PO Box 1067, 72001 Puebla, Pue., Mexico, and bCentro de Química, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, 72570 Puebla, Pue., Mexico
*Correspondence e-mail: angel.mendoza@correo.buap.mx
In the title compound, C21H17NS, the C=N double bond shows an E conformation. The dihedral angle between the mean planes of the naphthyl residue and the benzothiophene residue is 89.14 (6)°. The crystal packing is stabilized by intermolecular C—H⋯π interactions, building a ribbon structure along the a axis.
Related literature
For et al. (2011); Bernès et al. (2010); Jeon et al. (2005); Noyori (2005); Tanaka & Toda (2000).
see: GarcíaExperimental
Crystal data
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Data collection: CrysAlis PRO (Oxford Diffraction, 2006); cell CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: SHELXL2013; software used to prepare material for publication: SHELXL2013.
Supporting information
10.1107/S1600536813023611/bt6929sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536813023611/bt6929Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536813023611/bt6929Isup3.cml
Under solvent-free conditions, (S)-(-)-(1-naphthyl)ethylamine (0.21 g, 1.2 mmol) and benzo[b]thiophene-2-carboxaldehyde (0.20 g, 1.2 mmol) were mixed at room temperature obtaining a white solid. The crude was recrystallized from CH2Cl2 affording colorless crystals of the title compound. Yield 94%; mp 125–127 °C. Analysis: [α]D25 = +318 (cL, CHCl3). FT—IR (KBr): 1621 cm-1 (C=N). 1H NMR (400 MHz, CDCl3/TMS) δ = 1.76, 1.78 (d, 3H, CHCH3,), 5.40, 5.42, 5.44, 5.45(q, 1H, CH), 7.32–7.89 (m, 12 H Ar), 8.20, 8.23 (d, 1H cyclo S), 8.54 (s, 1 H, HC=N). 13C NMR (100 MHz, CDCl3/TMS) δ = 24.20 (CCH3), 64.87 (CHCH3), 122.66 (Ar), 123.58 (Ar), 124.14 (Ar), 124.43(Ar), 125.36 (Ar), 125.66 (Ar), 125.90 (Ar), 127.47 (Ar), 127.62 (Ar), 128.91 (Ar), 130.58(Ar), 133.93 (Ar), 139.31 (Ar),140.57 (Ar), 143.16 (Ar), 153.61 (HC=N). MS—EI: m/z= 315 (M+).
H atoms linked to C atoms were placed in geometrical idealized positions and refined as riding on their parent atoms, with C—H = 0.93–0.96 Å and with Uiso(H) = 1.2 Ueq(C) or 1.5 Ueq(methyl C).
Data collection: CrysAlis PRO (Oxford Diffraction, 2006); cell
CrysAlis PRO (Oxford Diffraction, 2006); data reduction: CrysAlis PRO (Oxford Diffraction, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: SHELXL2013 (Sheldrick, 2008); software used to prepare material for publication: SHELXL2013 (Sheldrick, 2008).Fig. 1. The molecular structure of title compound, with atom labels and 30% probability displacement ellipsoids for non-H atoms. |
C21H17NS | F(000) = 664 |
Mr = 315.42 | Dx = 1.263 Mg m−3 |
Orthorhombic, P212121 | Cu Kα radiation, λ = 1.54184 Å |
Hall symbol: P 2ac 2ab | Cell parameters from 2302 reflections |
a = 5.6423 (3) Å | θ = 4.8–73.7° |
b = 8.0808 (4) Å | µ = 1.70 mm−1 |
c = 36.3864 (19) Å | T = 298 K |
V = 1659.01 (15) Å3 | Plate, translucent colourless |
Z = 4 | 0.93 × 0.17 × 0.06 mm |
Oxford Diffraction Xcalibur (Atlas, Gemini) diffractometer | 2844 independent reflections |
Graphite monochromator | 2417 reflections with I > 2σ(I) |
Detector resolution: 10.5564 pixels mm-1 | Rint = 0.053 |
ω scans | θmax = 66.1°, θmin = 4.9° |
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2006) | h = −6→6 |
Tmin = 0.665, Tmax = 1 | k = −9→9 |
8690 measured reflections | l = −43→43 |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.040 | w = 1/[σ2(Fo2) + (0.0363P)2] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.092 | (Δ/σ)max < 0.001 |
S = 1.01 | Δρmax = 0.25 e Å−3 |
2844 reflections | Δρmin = −0.18 e Å−3 |
208 parameters | Absolute structure: Flack parameter determined using 839 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons & Flack (2004) |
0 restraints | Absolute structure parameter: 0.021 (17) |
C21H17NS | V = 1659.01 (15) Å3 |
Mr = 315.42 | Z = 4 |
Orthorhombic, P212121 | Cu Kα radiation |
a = 5.6423 (3) Å | µ = 1.70 mm−1 |
b = 8.0808 (4) Å | T = 298 K |
c = 36.3864 (19) Å | 0.93 × 0.17 × 0.06 mm |
Oxford Diffraction Xcalibur (Atlas, Gemini) diffractometer | 2844 independent reflections |
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2006) | 2417 reflections with I > 2σ(I) |
Tmin = 0.665, Tmax = 1 | Rint = 0.053 |
8690 measured reflections |
R[F2 > 2σ(F2)] = 0.040 | H-atom parameters constrained |
wR(F2) = 0.092 | Δρmax = 0.25 e Å−3 |
S = 1.01 | Δρmin = −0.18 e Å−3 |
2844 reflections | Absolute structure: Flack parameter determined using 839 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons & Flack (2004) |
208 parameters | Absolute structure parameter: 0.021 (17) |
0 restraints |
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. |
x | y | z | Uiso*/Ueq | ||
S1 | 0.66160 (15) | 0.33795 (10) | 0.20762 (2) | 0.0504 (2) | |
C13 | 0.8326 (7) | 0.6220 (4) | 0.07300 (9) | 0.0526 (8) | |
C5 | 0.8422 (8) | 0.4832 (4) | 0.30726 (10) | 0.0559 (8) | |
H5 | 0.9665 | 0.5439 | 0.3173 | 0.067* | |
C9 | 0.6413 (6) | 0.3627 (4) | 0.25514 (9) | 0.0453 (7) | |
C3 | 0.9946 (6) | 0.4998 (4) | 0.24067 (10) | 0.0492 (8) | |
H3 | 1.1323 | 0.5599 | 0.2451 | 0.059* | |
C4 | 0.8335 (6) | 0.4527 (4) | 0.26915 (10) | 0.0467 (7) | |
C2 | 0.9289 (5) | 0.4490 (4) | 0.20692 (11) | 0.0485 (7) | |
C1 | 1.0499 (6) | 0.4771 (4) | 0.17269 (10) | 0.0506 (8) | |
H1 | 1.182 | 0.546 | 0.1725 | 0.061* | |
C6 | 0.6675 (8) | 0.4233 (5) | 0.32929 (11) | 0.0612 (9) | |
H6 | 0.6735 | 0.4435 | 0.3544 | 0.073* | |
N1 | 0.9833 (5) | 0.4116 (4) | 0.14263 (9) | 0.0557 (7) | |
C12 | 0.9580 (6) | 0.4687 (4) | 0.07747 (10) | 0.0524 (8) | |
C8 | 0.4653 (6) | 0.3017 (4) | 0.27776 (11) | 0.0553 (9) | |
H8 | 0.3398 | 0.2412 | 0.2681 | 0.066* | |
C10 | 1.1270 (7) | 0.4460 (5) | 0.10929 (10) | 0.0563 (9) | |
H10 | 1.2155 | 0.549 | 0.113 | 0.068* | |
C19 | 0.6218 (8) | 0.5002 (6) | 0.02083 (11) | 0.0696 (11) | |
H19 | 0.51 | 0.5086 | 0.0021 | 0.083* | |
C18 | 0.6615 (8) | 0.6360 (5) | 0.04455 (10) | 0.0626 (9) | |
C11 | 1.3029 (8) | 0.3034 (6) | 0.10488 (12) | 0.0797 (13) | |
H11A | 1.4038 | 0.2983 | 0.1261 | 0.12* | |
H11B | 1.3975 | 0.3214 | 0.0833 | 0.12* | |
H11C | 1.2177 | 0.2012 | 0.1025 | 0.12* | |
C17 | 0.5403 (10) | 0.7867 (6) | 0.04014 (15) | 0.0848 (15) | |
H17 | 0.4272 | 0.7966 | 0.0217 | 0.102* | |
C7 | 0.4790 (7) | 0.3319 (5) | 0.31476 (11) | 0.0611 (10) | |
H7 | 0.362 | 0.2913 | 0.3303 | 0.073* | |
C14 | 0.8719 (9) | 0.7621 (5) | 0.09573 (12) | 0.0659 (11) | |
H14 | 0.9816 | 0.7552 | 0.1147 | 0.079* | |
C15 | 0.7523 (10) | 0.9062 (6) | 0.09026 (14) | 0.0851 (15) | |
H15 | 0.7825 | 0.997 | 0.1052 | 0.102* | |
C20 | 0.7450 (8) | 0.3587 (6) | 0.02515 (12) | 0.0700 (11) | |
H20 | 0.7182 | 0.2704 | 0.0093 | 0.084* | |
C16 | 0.5852 (10) | 0.9180 (6) | 0.06237 (15) | 0.0950 (18) | |
H16 | 0.5034 | 1.0167 | 0.0589 | 0.114* | |
C21 | 0.9123 (7) | 0.3431 (5) | 0.05316 (10) | 0.0610 (9) | |
H21 | 0.9956 | 0.2443 | 0.0554 | 0.073* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.0487 (4) | 0.0531 (4) | 0.0493 (4) | −0.0025 (4) | −0.0075 (4) | −0.0035 (4) |
C13 | 0.0587 (19) | 0.0561 (19) | 0.0431 (17) | 0.0004 (18) | 0.0125 (17) | 0.0075 (14) |
C5 | 0.059 (2) | 0.0567 (19) | 0.0522 (19) | −0.002 (2) | −0.0078 (19) | −0.0037 (16) |
C9 | 0.0447 (16) | 0.0411 (14) | 0.0501 (17) | 0.0052 (15) | −0.0051 (16) | 0.0011 (13) |
C3 | 0.0460 (19) | 0.0482 (17) | 0.054 (2) | −0.0028 (15) | −0.0055 (16) | −0.0030 (15) |
C4 | 0.0446 (17) | 0.0415 (14) | 0.0541 (18) | 0.0071 (16) | −0.0046 (18) | −0.0002 (14) |
C2 | 0.0472 (17) | 0.0431 (16) | 0.0552 (19) | 0.0040 (13) | −0.0013 (17) | 0.0042 (16) |
C1 | 0.0484 (18) | 0.0518 (18) | 0.051 (2) | 0.0041 (15) | −0.0027 (17) | 0.0030 (16) |
C6 | 0.070 (2) | 0.065 (2) | 0.0485 (19) | 0.005 (2) | 0.002 (2) | −0.0040 (18) |
N1 | 0.0539 (17) | 0.0614 (17) | 0.0517 (18) | 0.0019 (15) | 0.0030 (14) | 0.0063 (15) |
C12 | 0.055 (2) | 0.0558 (18) | 0.0461 (19) | 0.0009 (17) | 0.0109 (17) | 0.0041 (16) |
C8 | 0.0486 (19) | 0.0497 (19) | 0.068 (2) | −0.0031 (16) | −0.0031 (18) | −0.0008 (17) |
C10 | 0.058 (2) | 0.061 (2) | 0.0497 (19) | −0.0035 (18) | 0.0073 (18) | 0.0045 (16) |
C19 | 0.077 (3) | 0.082 (3) | 0.049 (2) | −0.005 (2) | −0.004 (2) | 0.006 (2) |
C18 | 0.067 (2) | 0.070 (2) | 0.0502 (19) | 0.007 (2) | 0.008 (2) | 0.0127 (18) |
C11 | 0.070 (3) | 0.103 (4) | 0.066 (3) | 0.022 (3) | 0.012 (2) | 0.017 (3) |
C17 | 0.093 (3) | 0.090 (3) | 0.072 (3) | 0.025 (3) | −0.001 (3) | 0.015 (3) |
C7 | 0.061 (2) | 0.060 (2) | 0.062 (2) | 0.003 (2) | 0.0126 (19) | 0.009 (2) |
C14 | 0.085 (3) | 0.059 (2) | 0.054 (2) | 0.003 (2) | 0.010 (2) | 0.0002 (17) |
C15 | 0.127 (4) | 0.060 (2) | 0.069 (3) | 0.007 (3) | 0.022 (3) | 0.000 (2) |
C20 | 0.087 (3) | 0.070 (3) | 0.053 (2) | −0.009 (2) | 0.003 (2) | −0.009 (2) |
C16 | 0.128 (5) | 0.073 (3) | 0.084 (4) | 0.039 (3) | 0.020 (3) | 0.016 (3) |
C21 | 0.073 (2) | 0.0584 (19) | 0.052 (2) | 0.0054 (18) | 0.0099 (18) | −0.0017 (19) |
S1—C9 | 1.744 (3) | C8—H8 | 0.93 |
S1—C2 | 1.755 (3) | C10—C11 | 1.529 (6) |
C13—C14 | 1.419 (5) | C10—H10 | 0.98 |
C13—C18 | 1.420 (6) | C19—C20 | 1.347 (6) |
C13—C12 | 1.436 (5) | C19—C18 | 1.414 (6) |
C5—C6 | 1.359 (6) | C19—H19 | 0.93 |
C5—C4 | 1.409 (5) | C18—C17 | 1.406 (6) |
C5—H5 | 0.93 | C11—H11A | 0.96 |
C9—C8 | 1.380 (5) | C11—H11B | 0.96 |
C9—C4 | 1.402 (5) | C11—H11C | 0.96 |
C3—C2 | 1.347 (5) | C17—C16 | 1.358 (7) |
C3—C4 | 1.430 (5) | C17—H17 | 0.93 |
C3—H3 | 0.93 | C7—H7 | 0.93 |
C2—C1 | 1.438 (5) | C14—C15 | 1.361 (6) |
C1—N1 | 1.272 (5) | C14—H14 | 0.93 |
C1—H1 | 0.93 | C15—C16 | 1.388 (7) |
C6—C7 | 1.399 (6) | C15—H15 | 0.93 |
C6—H6 | 0.93 | C20—C21 | 1.395 (6) |
N1—C10 | 1.485 (5) | C20—H20 | 0.93 |
C12—C21 | 1.371 (6) | C16—H16 | 0.93 |
C12—C10 | 1.511 (6) | C21—H21 | 0.93 |
C8—C7 | 1.371 (6) | ||
C9—S1—C2 | 90.70 (18) | C12—C10—H10 | 108.9 |
C14—C13—C18 | 117.9 (4) | C11—C10—H10 | 108.9 |
C14—C13—C12 | 123.0 (4) | C20—C19—C18 | 120.4 (4) |
C18—C13—C12 | 119.1 (3) | C20—C19—H19 | 119.8 |
C6—C5—C4 | 119.5 (4) | C18—C19—H19 | 119.8 |
C6—C5—H5 | 120.2 | C17—C18—C19 | 121.7 (4) |
C4—C5—H5 | 120.2 | C17—C18—C13 | 118.9 (4) |
C8—C9—C4 | 121.6 (3) | C19—C18—C13 | 119.4 (4) |
C8—C9—S1 | 126.7 (3) | C10—C11—H11A | 109.5 |
C4—C9—S1 | 111.7 (3) | C10—C11—H11B | 109.5 |
C2—C3—C4 | 113.9 (3) | H11A—C11—H11B | 109.5 |
C2—C3—H3 | 123.1 | C10—C11—H11C | 109.5 |
C4—C3—H3 | 123.1 | H11A—C11—H11C | 109.5 |
C9—C4—C5 | 118.4 (4) | H11B—C11—H11C | 109.5 |
C9—C4—C3 | 111.5 (3) | C16—C17—C18 | 121.2 (5) |
C5—C4—C3 | 130.1 (4) | C16—C17—H17 | 119.4 |
C3—C2—C1 | 127.6 (3) | C18—C17—H17 | 119.4 |
C3—C2—S1 | 112.3 (3) | C8—C7—C6 | 120.5 (4) |
C1—C2—S1 | 120.1 (3) | C8—C7—H7 | 119.7 |
N1—C1—C2 | 122.6 (3) | C6—C7—H7 | 119.7 |
N1—C1—H1 | 118.7 | C15—C14—C13 | 121.3 (5) |
C2—C1—H1 | 118.7 | C15—C14—H14 | 119.3 |
C5—C6—C7 | 121.1 (4) | C13—C14—H14 | 119.3 |
C5—C6—H6 | 119.5 | C14—C15—C16 | 120.2 (5) |
C7—C6—H6 | 119.5 | C14—C15—H15 | 119.9 |
C1—N1—C10 | 117.6 (3) | C16—C15—H15 | 119.9 |
C21—C12—C13 | 118.2 (3) | C19—C20—C21 | 120.7 (4) |
C21—C12—C10 | 121.5 (3) | C19—C20—H20 | 119.6 |
C13—C12—C10 | 120.2 (3) | C21—C20—H20 | 119.6 |
C7—C8—C9 | 118.8 (4) | C17—C16—C15 | 120.6 (4) |
C7—C8—H8 | 120.6 | C17—C16—H16 | 119.7 |
C9—C8—H8 | 120.6 | C15—C16—H16 | 119.7 |
N1—C10—C12 | 107.7 (3) | C12—C21—C20 | 122.1 (4) |
N1—C10—C11 | 107.4 (3) | C12—C21—H21 | 118.9 |
C12—C10—C11 | 114.9 (3) | C20—C21—H21 | 118.9 |
N1—C10—H10 | 108.9 | ||
C2—S1—C9—C8 | −178.8 (3) | C1—N1—C10—C11 | 95.0 (4) |
C2—S1—C9—C4 | 0.0 (2) | C21—C12—C10—N1 | −99.0 (4) |
C8—C9—C4—C5 | −1.2 (5) | C13—C12—C10—N1 | 78.2 (4) |
S1—C9—C4—C5 | 179.9 (3) | C21—C12—C10—C11 | 20.6 (5) |
C8—C9—C4—C3 | 178.8 (3) | C13—C12—C10—C11 | −162.1 (3) |
S1—C9—C4—C3 | −0.1 (3) | C20—C19—C18—C17 | 178.3 (4) |
C6—C5—C4—C9 | 0.9 (5) | C20—C19—C18—C13 | 0.0 (6) |
C6—C5—C4—C3 | −179.1 (3) | C14—C13—C18—C17 | 0.2 (6) |
C2—C3—C4—C9 | 0.2 (4) | C12—C13—C18—C17 | −179.6 (4) |
C2—C3—C4—C5 | −179.9 (4) | C14—C13—C18—C19 | 178.5 (4) |
C4—C3—C2—C1 | 179.4 (3) | C12—C13—C18—C19 | −1.2 (6) |
C4—C3—C2—S1 | −0.2 (4) | C19—C18—C17—C16 | −177.9 (5) |
C9—S1—C2—C3 | 0.1 (3) | C13—C18—C17—C16 | 0.4 (7) |
C9—S1—C2—C1 | −179.5 (3) | C9—C8—C7—C6 | 0.2 (6) |
C3—C2—C1—N1 | 173.8 (4) | C5—C6—C7—C8 | −0.5 (6) |
S1—C2—C1—N1 | −6.7 (5) | C18—C13—C14—C15 | −0.9 (6) |
C4—C5—C6—C7 | 0.0 (6) | C12—C13—C14—C15 | 178.9 (4) |
C2—C1—N1—C10 | −178.2 (3) | C13—C14—C15—C16 | 1.0 (7) |
C14—C13—C12—C21 | −177.7 (4) | C18—C19—C20—C21 | 0.4 (7) |
C18—C13—C12—C21 | 2.0 (5) | C18—C17—C16—C15 | −0.3 (8) |
C14—C13—C12—C10 | 5.0 (5) | C14—C15—C16—C17 | −0.4 (8) |
C18—C13—C12—C10 | −175.3 (3) | C13—C12—C21—C20 | −1.7 (6) |
C4—C9—C8—C7 | 0.7 (5) | C10—C12—C21—C20 | 175.6 (3) |
S1—C9—C8—C7 | 179.4 (3) | C19—C20—C21—C12 | 0.4 (6) |
C1—N1—C10—C12 | −140.7 (3) |
Cg1 and Cg2 are the centroids of the S1/C2/C3/C4/C9, C12/C13/C18/C19/C20/C21 rings, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
C8—H8···Cg1i | 0.93 | 2.73 | 3.491 (4) | 139 |
C11—H11B···Cg2ii | 0.96 | 2.59 | 3.724 (5) | 149 |
Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) x+1, y, z. |
Cg1 and Cg2 are the centroids of the S1/C2/C3/C4/C9, C12/C13/C18/C19/C20/C21 rings, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
C8—H8···Cg1i | 0.93 | 2.73 | 3.491 (4) | 139 |
C11—H11B···Cg2ii | 0.96 | 2.59 | 3.724 (5) | 149 |
Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) x+1, y, z. |
Acknowledgements
Support from VIEP-UAP (GUPJ-NAT10-G) is acknowledged.
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Schiff base compounds are widely studied and used, attracting much attention in both organic synthesis and metal ion complexation. Recently, we have focused our attention on the synthesis of chiral Schiff bases by using green techniques (García et al., 2011; Bernès et al., 2010). In continuation of this work, we synthesized the title compound using the solvent-free approach because the reactions occur under mild conditions and usually require easier workup procedures and simpler equipment. Other advantages of solvent-free reactions encompass cost saving, decreased reaction times along with reduced energy consumption, as well as increased safety (Jeon et al., 2005; Noyori, 2005; Tanaka & Toda, 2000)
The C=N double bond shows an E configuration. The dihedral angle between the mean planes of the naphthyl residue and the benzothiophene residue is 90.86 (6)°. The crystal packing is stabilized by intermolecular C—H···π interactions (Table 2; cg1 is the centroid of the ring composed of S1, C2, C3 C4, and C9, cg2 is the centroid of the ring composed of C12, C13, C18, C19, C20, and C21).