organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

(S)-(+)-1-(1-Naphth­yl)-1-(2-thienylmethyl­ene)ethyl­amine

aFacultad de Ciencias Químicas, UANL, Licenciatura en Química Industrial, Ciudad Universitaria, Monterrey, NL, Mexico, bLaboratorio de Síntesis de Complejos, Facultad de Ciencias Químicas, BUAP, AP 1067, 72001 Puebla, Pue., Mexico, and cDEP Facultad de Ciencias Químicas, UANL, Guerrero y Progreso S/N, Col. Treviño, 64570 Monterrey, NL, Mexico
*Correspondence e-mail: sylvain_bernes@hotmail.com

(Received 1 June 2009; accepted 11 June 2009; online 20 June 2009)

The title chiral imine, C17H15NS, has been obtained via a direct synthesis route. The imine group displays the common E configuration, and is almost coplanar with the thio­phene heterocycle; the dihedral angle between the C=N—C group and the thio­phene ring is 5.1 (8)°. In contrast, the naphthyl group makes an angle of 83.79 (13)° with the thio­phene ring. The observed solid-state mol­ecular conformation is suitable for the use of this mol­ecule as an N,S-bidentate Schiff base ligand. The mol­ecular packing features double C—H⋯π inter­actions between naphthyl groups of neighboring mol­ecules, which form chains in the [100] direction. The crystal structure is further stabilized by a short C—H⋯π contact involving the methyl group and one ring of a naphthyl group. The resulting two-dimensional network is completed by a weak inter­molecular C—H(imine)⋯π(thio­phene) inter­action.

Related literature

For background to direct synthesis, see: Tanaka & Toda (2000[Tanaka, K. & Toda, F. (2000). Chem. Rev. 100, 1025-1074.]); Jeon et al. (2005[Jeon, S.-J., Li, H. & Walsh, P. J. (2005). J. Am. Chem. Soc. 127, 16416-16425.]); Tovar et al. (2007[Tovar, A., Peña, U., Hernández, G., Portillo, R. & Gutiérrez, R. (2007). Synthesis, pp. 22-24.]). For the configuration and conformation of imines derived from thio­phene, see: Arjona et al. (1986[Arjona, O., Carreiro, C., Perez Ossorio, R., Plumet, J., Cativiela, C., Mayoral, J. A. & Melendez, E. (1986). An. Quim. 82, 115-118.]).

[Scheme 1]

Experimental

Crystal data
  • C17H15NS

  • Mr = 265.36

  • Orthorhombic, P 21 21 21

  • a = 5.5274 (14) Å

  • b = 7.990 (2) Å

  • c = 31.517 (8) Å

  • V = 1392.0 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.22 mm−1

  • T = 298 K

  • 0.50 × 0.36 × 0.04 mm

Data collection
  • Siemens P4 diffractometer

  • Absorption correction: ψ scan (XSCANS; Siemens, 1996[Siemens (1996). XSCANS. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]) Tmin = 0.802, Tmax = 0.991

  • 4462 measured reflections

  • 2446 independent reflections

  • 1280 reflections with I > 2σ(I)

  • Rint = 0.045

  • 2 standard reflections every 48 reflections intensity decay: 1.8%

Refinement
  • R[F2 > 2σ(F2)] = 0.059

  • wR(F2) = 0.174

  • S = 1.56

  • 2446 reflections

  • 174 parameters

  • H-atom parameters constrained

  • Δρmax = 0.31 e Å−3

  • Δρmin = −0.39 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 946 Friedel pairs

  • Flack parameter: 0.2 (2)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C9—H9B⋯CgAi 0.96 2.85 3.682 (6) 145
C6—H6A⋯CgBii 0.93 3.03 3.891 (5) 155
C13—H13A⋯CgCiii 0.93 3.54 4.399 (6) 155
C15—H15A⋯CgAiii 0.93 3.22 4.030 (6) 147
Symmetry codes: (i) x+1, y, z; (ii) [-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) [x-{\script{1\over 2}}, -y+{\script{5\over 2}}, -z]. CgA is the centroid of ring C10–C14/C19, CgB is the centroid of the thio­phene ring and CgC is the centroid of ring C14–C19.

Data collection: XSCANS (Siemens, 1996[Siemens (1996). XSCANS. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Nowadays, there is an increasing interest in the use of environmentally benign reagents and conditions, leading particularly to solvent-free procedures. Avoiding organic solvents during the reactions in organic synthesis affords clean, efficient and economical features: safety is largely increased, working is considerably simplified, cost is reduced, increased amounts of reactants can be used, etc. (Tanaka & Toda, 2000; Jeon et al., 2005).

On the other hand, imines continue to attract much attention, mainly due to their versatile coordination behavior and the interesting properties of their metal complexes. Continuing our work on the synthesis of chiral imines (Tovar et al., 2007), we synthesized the title compound under solvent-free conditions (see Experimental) and report here its X-ray crystal structure.

The molecule is stabilized in the solid state as an E-trans aldimine (Fig. 1), which has been shown to be the preferred configuration for imine systems derived from thiophene (Arjona et al., 1986). By conjugation, the imine group C6/N7/C8 is almost coplanar with the thiophene ring S1/C2/C3/C4/C5, with a dihedral angle of 5.1 (8)°. In contrast, the naphthyl group is almost normal to the thiophene ring, at 83.79 (13)°. The crystal packing features a number of intermolecular C—H···π contacts (Fig. 2), the strongest involving the methyl group and a naphthyl group of a symmetry-related molecule. Naphthyl systems aggregate through double C—H···π interactions, forming chains along the [100] direction. The set of contacts results in a two-dimensional framework of efficiently stacked molecules.

Related literature top

For background to direct synthesis, see: Tanaka & Toda (2000); Jeon et al. (2005); Tovar et al. (2007). For the configuration and conformation of imines derived from thiophene, see: Arjona et al. (1986). CgA is the centroid of ring C10–C14/C19, CgB is the centroid of the thiophene ring and CgC is the centroid of ring C14–C19

Experimental top

Under solvent-free conditions, (S)-(-)-(1-naphthyl)ethylamine (213 mg, 1.24 mmol) and 2-thiophenecarboxaldehyde (139 mg, 1.24 mmol) were mixed at 298 K, giving a white solid. The crude product was recrystallized from CH2Cl2, affording colorless crystals of the title compound. Yield 87%; m.p. 345 K. Analytical data are in agreement with the structure determined by X-ray diffraction (see archived CIF).

Refinement top

The title molecule crystallizes as thin plates, and the selected crystal was a poorly diffracting sample, limiting data resolution. All H atoms were placed in idealized positions and refined as riding on their carrier C atoms, with bond lengths fixed to 0.93 (aromatic CH), 0.96 (methyl CH3), and 0.98 Å (methine CH). Isotropic displacement parameters were calculated as Uiso(H) = 1.5Ueq(carrier atom) for the methyl group and Uiso(H) = 1.2Ueq(carrier atom) otherwise. The absolute configuration was assigned by refinement of a Flack parameter, and agrees with the chirality expected from the synthetic route.

Computing details top

Data collection: XSCANS (Siemens, 1996); cell refinement: XSCANS (Siemens, 1996); data reduction: XSCANS (Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The title molecule with displacement ellipsoids for non-H atoms shown at the 30% probability level. Hydrogen atoms are shown as spheres of arbitrary radius.
[Figure 2] Fig. 2. A part of the crystal structure of the title compound, viewed down [010]. The color scheme is used for the sake of clarity. Dashed lines represent C—H···π interactions in the crystal structure, and the centroids of involved π systems have been represented by red spheres. H atoms not involved in the network of intermolecular contacts have been omitted.
(S)-(+)-1-(1-Naphthyl)-1-(2-thienylmethylene)ethylamine top
Crystal data top
C17H15NSDx = 1.266 Mg m3
Mr = 265.36Melting point: 345 K
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 68 reflections
a = 5.5274 (14) Åθ = 4.9–11.5°
b = 7.990 (2) ŵ = 0.22 mm1
c = 31.517 (8) ÅT = 298 K
V = 1392.0 (6) Å3Plate, colourless
Z = 40.50 × 0.36 × 0.04 mm
F(000) = 560
Data collection top
Siemens P4
diffractometer
1280 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.045
Graphite monochromatorθmax = 25.0°, θmin = 2.6°
ω scansh = 66
Absorption correction: ψ scan
(XSCANS; Siemens, 1996)
k = 99
Tmin = 0.802, Tmax = 0.991l = 3737
4462 measured reflections2 standard reflections every 48 reflections
2446 independent reflections intensity decay: 1.8%
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.059 w = 1/[σ2(Fo2) + (0.05P)2]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.174(Δ/σ)max < 0.001
S = 1.56Δρmax = 0.31 e Å3
2446 reflectionsΔρmin = 0.39 e Å3
174 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.046 (6)
0 constraintsAbsolute structure: Flack (1983), 946 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.2 (2)
Secondary atom site location: difference Fourier map
Crystal data top
C17H15NSV = 1392.0 (6) Å3
Mr = 265.36Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 5.5274 (14) ŵ = 0.22 mm1
b = 7.990 (2) ÅT = 298 K
c = 31.517 (8) Å0.50 × 0.36 × 0.04 mm
Data collection top
Siemens P4
diffractometer
1280 reflections with I > 2σ(I)
Absorption correction: ψ scan
(XSCANS; Siemens, 1996)
Rint = 0.045
Tmin = 0.802, Tmax = 0.9912 standard reflections every 48 reflections
4462 measured reflections intensity decay: 1.8%
2446 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.059H-atom parameters constrained
wR(F2) = 0.174Δρmax = 0.31 e Å3
S = 1.56Δρmin = 0.39 e Å3
2446 reflectionsAbsolute structure: Flack (1983), 946 Friedel pairs
174 parametersAbsolute structure parameter: 0.2 (2)
0 restraints
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
S10.0890 (3)0.77472 (18)0.23563 (4)0.0851 (5)
C20.0387 (11)0.7930 (7)0.28848 (16)0.0838 (16)
H2A0.08520.73770.30270.101*
C30.1958 (10)0.8951 (7)0.30739 (17)0.0808 (16)
H3A0.19200.91890.33630.097*
C40.3675 (11)0.9631 (6)0.27948 (16)0.0765 (15)
H4A0.49061.03590.28750.092*
C50.3292 (8)0.9077 (6)0.23880 (16)0.0637 (12)
C60.4666 (10)0.9518 (6)0.20103 (16)0.0709 (14)
H6A0.58651.03310.20300.085*
N70.4278 (8)0.8830 (5)0.16565 (12)0.0732 (11)
C80.5830 (11)0.9318 (6)0.12949 (14)0.0743 (14)
H8A0.66481.03740.13620.089*
C90.7706 (10)0.7968 (8)0.12312 (17)0.0982 (19)
H9A0.88350.79890.14620.147*
H9B0.85500.81610.09700.147*
H9C0.69240.68960.12210.147*
C100.4174 (10)0.9587 (6)0.09162 (14)0.0679 (13)
C110.3745 (10)0.8354 (6)0.06322 (15)0.0771 (14)
H11A0.45640.73440.06620.093*
C120.2109 (10)0.8542 (7)0.02938 (16)0.0837 (17)
H12A0.18580.76620.01060.100*
C130.0910 (12)0.9986 (7)0.02414 (17)0.0835 (16)
H13A0.01801.00990.00190.100*
C140.1289 (10)1.1329 (7)0.05212 (16)0.0757 (14)
C150.0159 (12)1.2883 (8)0.04640 (19)0.101 (2)
H15A0.09131.30140.02390.121*
C160.0570 (16)1.4195 (9)0.0723 (2)0.110 (2)
H16A0.02241.52050.06770.132*
C170.2162 (13)1.4043 (8)0.1058 (2)0.0980 (19)
H17A0.24461.49500.12360.118*
C180.3321 (11)1.2564 (7)0.11269 (16)0.0850 (16)
H18A0.43781.24770.13550.102*
C190.2965 (10)1.1158 (6)0.08620 (14)0.0702 (14)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0830 (9)0.0941 (10)0.0780 (9)0.0071 (9)0.0027 (8)0.0051 (8)
C20.092 (4)0.093 (4)0.066 (3)0.000 (4)0.010 (3)0.006 (3)
C30.093 (4)0.083 (4)0.067 (3)0.008 (4)0.008 (3)0.003 (3)
C40.085 (4)0.074 (3)0.071 (3)0.009 (3)0.001 (3)0.005 (3)
C50.058 (3)0.063 (3)0.070 (3)0.006 (2)0.003 (2)0.002 (3)
C60.069 (4)0.071 (3)0.073 (3)0.002 (3)0.005 (3)0.000 (3)
N70.075 (3)0.082 (3)0.062 (2)0.001 (3)0.003 (2)0.001 (2)
C80.078 (3)0.079 (3)0.066 (3)0.000 (3)0.003 (3)0.008 (3)
C90.086 (4)0.119 (5)0.090 (4)0.029 (4)0.004 (3)0.007 (4)
C100.073 (3)0.069 (3)0.062 (3)0.002 (3)0.001 (3)0.003 (3)
C110.089 (4)0.073 (3)0.070 (3)0.004 (3)0.001 (3)0.001 (3)
C120.091 (4)0.085 (4)0.076 (4)0.002 (4)0.003 (3)0.010 (3)
C130.088 (4)0.093 (4)0.070 (3)0.002 (4)0.007 (3)0.003 (3)
C140.077 (4)0.078 (3)0.072 (3)0.006 (3)0.002 (3)0.008 (3)
C150.117 (5)0.096 (4)0.090 (4)0.026 (4)0.006 (4)0.018 (4)
C160.134 (6)0.083 (4)0.112 (5)0.024 (5)0.014 (5)0.013 (4)
C170.117 (5)0.078 (4)0.099 (4)0.007 (4)0.017 (4)0.005 (4)
C180.097 (4)0.077 (4)0.081 (3)0.006 (4)0.009 (3)0.007 (3)
C190.077 (3)0.072 (3)0.062 (3)0.001 (3)0.006 (3)0.003 (3)
Geometric parameters (Å, º) top
S1—C21.695 (5)C10—C111.352 (6)
S1—C51.703 (5)C10—C191.432 (6)
C2—C31.332 (7)C11—C121.407 (7)
C2—H2A0.9300C11—H11A0.9300
C3—C41.404 (7)C12—C131.341 (7)
C3—H3A0.9300C12—H12A0.9300
C4—C51.373 (6)C13—C141.405 (7)
C4—H4A0.9300C13—H13A0.9300
C5—C61.455 (6)C14—C151.401 (7)
C6—N71.261 (5)C14—C191.425 (7)
C6—H6A0.9300C15—C161.349 (7)
N7—C81.479 (6)C15—H15A0.9300
C8—C91.509 (7)C16—C171.378 (9)
C8—C101.519 (7)C16—H16A0.9300
C8—H8A0.9800C17—C181.361 (8)
C9—H9A0.9600C17—H17A0.9300
C9—H9B0.9600C18—C191.414 (6)
C9—H9C0.9600C18—H18A0.9300
C2—S1—C591.0 (3)C11—C10—C8121.5 (5)
C3—C2—S1112.7 (5)C19—C10—C8119.9 (4)
C3—C2—H2A123.7C10—C11—C12122.5 (5)
S1—C2—H2A123.7C10—C11—H11A118.8
C2—C3—C4113.4 (5)C12—C11—H11A118.8
C2—C3—H3A123.3C13—C12—C11120.2 (5)
C4—C3—H3A123.3C13—C12—H12A119.9
C5—C4—C3110.8 (5)C11—C12—H12A119.9
C5—C4—H4A124.6C12—C13—C14120.4 (6)
C3—C4—H4A124.6C12—C13—H13A119.8
C4—C5—C6127.2 (4)C14—C13—H13A119.8
C4—C5—S1112.1 (4)C15—C14—C13122.0 (5)
C6—C5—S1120.6 (4)C15—C14—C19118.1 (5)
N7—C6—C5121.9 (5)C13—C14—C19119.8 (5)
N7—C6—H6A119.0C16—C15—C14122.4 (6)
C5—C6—H6A119.0C16—C15—H15A118.8
C6—N7—C8117.9 (4)C14—C15—H15A118.8
N7—C8—C9108.2 (4)C15—C16—C17120.1 (6)
N7—C8—C10107.0 (4)C15—C16—H16A119.9
C9—C8—C10114.2 (4)C17—C16—H16A119.9
N7—C8—H8A109.1C18—C17—C16119.9 (6)
C9—C8—H8A109.1C18—C17—H17A120.0
C10—C8—H8A109.1C16—C17—H17A120.0
C8—C9—H9A109.5C17—C18—C19122.0 (6)
C8—C9—H9B109.5C17—C18—H18A119.0
H9A—C9—H9B109.5C19—C18—H18A119.0
C8—C9—H9C109.5C18—C19—C14117.3 (5)
H9A—C9—H9C109.5C18—C19—C10124.1 (5)
H9B—C9—H9C109.5C14—C19—C10118.5 (5)
C11—C10—C19118.5 (5)
C5—S1—C2—C30.2 (4)C11—C12—C13—C140.6 (9)
S1—C2—C3—C40.4 (6)C12—C13—C14—C15176.8 (5)
C2—C3—C4—C50.5 (7)C12—C13—C14—C190.2 (9)
C3—C4—C5—C6179.1 (5)C13—C14—C15—C16177.9 (6)
C3—C4—C5—S10.4 (6)C19—C14—C15—C161.3 (9)
C2—S1—C5—C40.1 (4)C14—C15—C16—C170.5 (11)
C2—S1—C5—C6179.4 (4)C15—C16—C17—C180.1 (10)
C4—C5—C6—N7174.2 (5)C16—C17—C18—C190.6 (9)
S1—C5—C6—N76.4 (6)C17—C18—C19—C141.4 (8)
C5—C6—N7—C8177.8 (4)C17—C18—C19—C10178.7 (5)
C6—N7—C8—C9101.4 (5)C15—C14—C19—C181.7 (7)
C6—N7—C8—C10135.0 (5)C13—C14—C19—C18178.4 (5)
N7—C8—C10—C1194.5 (6)C15—C14—C19—C10178.5 (5)
C9—C8—C10—C1125.3 (7)C13—C14—C19—C101.7 (7)
N7—C8—C10—C1983.5 (6)C11—C10—C19—C18177.6 (5)
C9—C8—C10—C19156.7 (5)C8—C10—C19—C184.3 (8)
C19—C10—C11—C121.9 (8)C11—C10—C19—C142.5 (7)
C8—C10—C11—C12176.1 (5)C8—C10—C19—C14175.5 (5)
C10—C11—C12—C130.3 (8)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C9—H9B···CgAi0.962.853.682 (6)145
C6—H6A···CgBii0.933.033.891 (5)155
C13—H13A···CgCiii0.933.544.399 (6)155
C15—H15A···CgAiii0.933.224.030 (6)147
Symmetry codes: (i) x+1, y, z; (ii) x+1, y+1/2, z+1/2; (iii) x1/2, y+5/2, z.

Experimental details

Crystal data
Chemical formulaC17H15NS
Mr265.36
Crystal system, space groupOrthorhombic, P212121
Temperature (K)298
a, b, c (Å)5.5274 (14), 7.990 (2), 31.517 (8)
V3)1392.0 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.22
Crystal size (mm)0.50 × 0.36 × 0.04
Data collection
DiffractometerSiemens P4
diffractometer
Absorption correctionψ scan
(XSCANS; Siemens, 1996)
Tmin, Tmax0.802, 0.991
No. of measured, independent and
observed [I > 2σ(I)] reflections
4462, 2446, 1280
Rint0.045
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.059, 0.174, 1.56
No. of reflections2446
No. of parameters174
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.31, 0.39
Absolute structureFlack (1983), 946 Friedel pairs
Absolute structure parameter0.2 (2)

Computer programs: XSCANS (Siemens, 1996), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), Mercury (Macrae et al., 2006).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C9—H9B···CgAi0.962.853.682 (6)145
C6—H6A···CgBii0.933.033.891 (5)155
C13—H13A···CgCiii0.933.544.399 (6)155
C15—H15A···CgAiii0.933.224.030 (6)147
Symmetry codes: (i) x+1, y, z; (ii) x+1, y+1/2, z+1/2; (iii) x1/2, y+5/2, z.
 

Acknowledgements

Partial support from VIEP-UAP (GUPJ-NAT08-G) is acknowledged.

References

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First citationFlack, H. D. (1983). Acta Cryst. A39, 876–881.  CrossRef CAS Web of Science IUCr Journals Google Scholar
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