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

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ISSN: 2056-9890

Crystal structure of (E)-(benzyl­­idene)(pyridin-2-ylmeth­yl)amine

aDepartment of Chemistry and Biology, Ryerson University, Toronto, Ontario, M5B 2K3, Canada, and bDepartment of Chemistry, University of Toronto, Toronto, Ontario, Canada, M5S 3H6
*Correspondence e-mail: alough@chem.utoronto.ca

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 19 November 2015; accepted 4 December 2015; online 12 December 2015)

In the title mol­ecule, C13H12N2, all non-H atoms, except for those of the pyridine ring, are essentially coplanar, with an r.m.s. deviation of 0.025 Å. The mean plane of these atoms forms a dihedral angle of 80.98 (4)° with the pyridine ring. In the crystal, weak C—H⋯π inter­actions link the mol­ecules, forming a three-dimensional network.

1. Related literature

For the synthesis of the title compound, see: Pointeau et al. (1986[Pointeau, P., Patin, H., Mousser, A. & Le Marouille, J.-Y. (1986). J. Organomet. Chem. 312, 263-276.]); Ménard et al. (1994[Ménard, L., Fontaine, L. & Brosse, J.-C. (1994). React. Polym. 23, 201-212.]). For the crystal structures of related Schiff base compounds, see: Pointeau et al. (1986[Pointeau, P., Patin, H., Mousser, A. & Le Marouille, J.-Y. (1986). J. Organomet. Chem. 312, 263-276.]); Olivo et al. (2015[Olivo, G., Nardi, M., Vìdal, D., Barbieri, A., Lapi, A., Gómez, L., Lanzalunga, O., Costas, M. & Di Stefano, S. (2015). Inorg. Chem. 54, 10141-10152.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C13H12N2

  • Mr = 196.25

  • Monoclinic, P 21 /c

  • a = 9.8029 (13) Å

  • b = 10.4175 (13) Å

  • c = 11.4984 (15) Å

  • β = 115.138 (4)°

  • V = 1063.0 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.07 mm−1

  • T = 147 K

  • 0.32 × 0.22 × 0.11 mm

2.2. Data collection

  • Bruker Kappa APEX DUO CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2014[Bruker (2014). APEX2, SAINT and SADABS, Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.687, Tmax = 0.746

  • 5375 measured reflections

  • 2427 independent reflections

  • 1712 reflections with I > 2σ(I)

  • Rint = 0.033

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.045

  • wR(F2) = 0.117

  • S = 1.02

  • 2427 reflections

  • 136 parameters

  • H-atom parameters constrained

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of rings C8–C13 and N1/C1–C5, respectively.

D—H⋯A D—H H⋯A DA D—H⋯A
C2—H2ACg1i 0.95 2.87 3.6655 (19) 142
C3—H3ACg1ii 0.95 2.71 3.4436 (19) 135
C7—H7ACg2iii 0.95 2.93 3.716 (2) 140
C12—H12ACg2iv 0.95 2.91 3.484 (2) 120
Symmetry codes: (i) x, y-1, z; (ii) [x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (iii) [-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iv) [-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2014[Bruker (2014). APEX2, SAINT and SADABS, Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2014[Bruker (2014). APEX2, SAINT and SADABS, Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXT (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]); molecular graphics: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) and SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXL2014.

Supporting information


Structural commentary top

The synthesis of the title compound was first reported by Pointeau et al. (1986) who described the isolation of an oily mixture of both E and Z isomers. Ménard et al. (1994) provided additional synthetic and characterization details for the title compound. Schiff bases such as the title compound are ideal in the preparation of six coordinate stannanes. The bidentate ligand acts to moderate the Lewis acidity by providing additional electron density to Sn, while at the same time reducing nucleophilic attack from species such as water. The incorporation of this ligand would change the coordination number at the Sn centre from tetra­hedral to a pseudo o­cta­hedral. The isolation of only a single isomer in the crystal structure of the title molecule may be a result of the dehydrating conditions of the reaction where all evolved moisture from the condensation was absorbed by activated molecular sieves.

The molecular structure of the title compound is shown in Fig. 1. In the molecule, all non-H atoms except for those of the pyridine ring are essentially coplanar with an r.m.s. deviation of 0.025 Å and the mean plane of these atoms (C8–C13/C7/N2/C6) forms a dihedral angle of 80.98 (4)° with the pyridine ring (N1/C1–C5).

In the crystal, weak C—H···π inter­actions link molecules forming a three-dimensional network (Fig. 2).

Synthesis and crystallization top

In a sealed 100 ml 3-neck round bottom flask equipped with a magnetic stir bar, 5 grams of 4Å molecular sieves were flamed dried and placed under dynamic vacuum for over 1 hr. Dried CH2Cl2 (25 mL), benzaldehyde (900 mg, 8.48 mmol) and 2-picolyl­amine (917 mg, 8.48 mmol) were placed into a flask and stirred for 12 hr under N2. The resulting slurry was then filtered through Celite and the organic layer washed with 1N NaCl (2 x 10 ml). The solution was then filtered and the solvent removed under vacuum to yield colourless needle crystals. Analysis by NMR spectroscopy (1H NMR) was similar to that previously reported by Pointeau et al. (1986). Yield: 92% (1.65 g, 8.41 mmol) 1H NMR (CDCl3): δ 4.97(s, 2H), 7.17 (ddt, 2J = 5 Hz, 3J = 1Hz, 1H), 7.43 (m, 4H), 7.66 (td, 2J = 5 Hz, 3J = 2 Hz, 1H), 7.815 (dd, 2J = 5Hz, 3J = 2Hz, 2H), 8.48 (s, 1H), 8.58 (d, 3J = 2Hz, 1H) ppm; 13C NMR 66.79, 121.98, 122.25, 128.32, 128.60, 130.87, 136.09, 136.63, 149.25, 159.31 ppm. Analysis HRMS: [M+H] Calc: 197.10787; Found 197.10804.

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 1. Hydrogen atoms bonded to C atoms were placed in calculated positions with C—H distances 0.95 and 0.99 Å and included in the refinement in a riding-model approximation with Uiso(H) = 1.2Ueq(C).

Related literature top

For the synthesis of the title compound, see: Pointeau et al. (1986); Ménard et al. (1994). For the crystal structures of related Schiff base compounds, see: Pointeau et al. (1986); Olivo et al. (2015).

Structure description top

The synthesis of the title compound was first reported by Pointeau et al. (1986) who described the isolation of an oily mixture of both E and Z isomers. Ménard et al. (1994) provided additional synthetic and characterization details for the title compound. Schiff bases such as the title compound are ideal in the preparation of six coordinate stannanes. The bidentate ligand acts to moderate the Lewis acidity by providing additional electron density to Sn, while at the same time reducing nucleophilic attack from species such as water. The incorporation of this ligand would change the coordination number at the Sn centre from tetra­hedral to a pseudo o­cta­hedral. The isolation of only a single isomer in the crystal structure of the title molecule may be a result of the dehydrating conditions of the reaction where all evolved moisture from the condensation was absorbed by activated molecular sieves.

The molecular structure of the title compound is shown in Fig. 1. In the molecule, all non-H atoms except for those of the pyridine ring are essentially coplanar with an r.m.s. deviation of 0.025 Å and the mean plane of these atoms (C8–C13/C7/N2/C6) forms a dihedral angle of 80.98 (4)° with the pyridine ring (N1/C1–C5).

In the crystal, weak C—H···π inter­actions link molecules forming a three-dimensional network (Fig. 2).

For the synthesis of the title compound, see: Pointeau et al. (1986); Ménard et al. (1994). For the crystal structures of related Schiff base compounds, see: Pointeau et al. (1986); Olivo et al. (2015).

Synthesis and crystallization top

In a sealed 100 ml 3-neck round bottom flask equipped with a magnetic stir bar, 5 grams of 4Å molecular sieves were flamed dried and placed under dynamic vacuum for over 1 hr. Dried CH2Cl2 (25 mL), benzaldehyde (900 mg, 8.48 mmol) and 2-picolyl­amine (917 mg, 8.48 mmol) were placed into a flask and stirred for 12 hr under N2. The resulting slurry was then filtered through Celite and the organic layer washed with 1N NaCl (2 x 10 ml). The solution was then filtered and the solvent removed under vacuum to yield colourless needle crystals. Analysis by NMR spectroscopy (1H NMR) was similar to that previously reported by Pointeau et al. (1986). Yield: 92% (1.65 g, 8.41 mmol) 1H NMR (CDCl3): δ 4.97(s, 2H), 7.17 (ddt, 2J = 5 Hz, 3J = 1Hz, 1H), 7.43 (m, 4H), 7.66 (td, 2J = 5 Hz, 3J = 2 Hz, 1H), 7.815 (dd, 2J = 5Hz, 3J = 2Hz, 2H), 8.48 (s, 1H), 8.58 (d, 3J = 2Hz, 1H) ppm; 13C NMR 66.79, 121.98, 122.25, 128.32, 128.60, 130.87, 136.09, 136.63, 149.25, 159.31 ppm. Analysis HRMS: [M+H] Calc: 197.10787; Found 197.10804.

Refinement details top

Crystal data, data collection and structure refinement details are summarized in Table 1. Hydrogen atoms bonded to C atoms were placed in calculated positions with C—H distances 0.95 and 0.99 Å and included in the refinement in a riding-model approximation with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2014); cell refinement: SAINT (Bruker, 2014); data reduction: SAINT (Bruker, 2014); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: PLATON (Spek, 2009) and SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2015b).

Figures top
[Figure 1] Fig. 1. The molecular structure of title compound, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. A partial view of the crystal packing of the title compound, with the weak C—H···π interactions shown as dashed lines (see Table 1).
(E)-(Benzylidene)(pyridin-2-ylmethyl)amine top
Crystal data top
C13H12N2F(000) = 416
Mr = 196.25Dx = 1.226 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 9.8029 (13) ÅCell parameters from 2108 reflections
b = 10.4175 (13) Åθ = 2.8–27.4°
c = 11.4984 (15) ŵ = 0.07 mm1
β = 115.138 (4)°T = 147 K
V = 1063.0 (2) Å3Needle, colourless
Z = 40.32 × 0.22 × 0.11 mm
Data collection top
Bruker Kappa APEX DUO CCD
diffractometer
1712 reflections with I > 2σ(I)
Radiation source: sealed tube with multi-layer opticsRint = 0.033
φ and ω scansθmax = 27.5°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2014)
h = 1211
Tmin = 0.687, Tmax = 0.746k = 1313
5375 measured reflectionsl = 1214
2427 independent reflections
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.045H-atom parameters constrained
wR(F2) = 0.117 w = 1/[σ2(Fo2) + (0.0497P)2 + 0.1728P]
where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max = 0.001
2427 reflectionsΔρmax = 0.17 e Å3
136 parametersΔρmin = 0.20 e Å3
Crystal data top
C13H12N2V = 1063.0 (2) Å3
Mr = 196.25Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.8029 (13) ŵ = 0.07 mm1
b = 10.4175 (13) ÅT = 147 K
c = 11.4984 (15) Å0.32 × 0.22 × 0.11 mm
β = 115.138 (4)°
Data collection top
Bruker Kappa APEX DUO CCD
diffractometer
2427 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2014)
1712 reflections with I > 2σ(I)
Tmin = 0.687, Tmax = 0.746Rint = 0.033
5375 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0450 restraints
wR(F2) = 0.117H-atom parameters constrained
S = 1.02Δρmax = 0.17 e Å3
2427 reflectionsΔρmin = 0.20 e Å3
136 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.15560 (14)0.68211 (12)0.22241 (12)0.0330 (3)
N20.22487 (16)0.95797 (12)0.30974 (14)0.0386 (3)
C10.20176 (19)0.56274 (15)0.21743 (17)0.0408 (4)
H1A0.17940.52730.13520.049*
C20.27894 (19)0.48812 (15)0.32253 (19)0.0452 (5)
H2A0.30940.40360.31340.054*
C30.31131 (17)0.53793 (16)0.44134 (18)0.0435 (5)
H3A0.36470.48840.51650.052*
C40.26525 (17)0.66143 (16)0.45063 (15)0.0363 (4)
H4A0.28640.69820.53210.044*
C50.18781 (16)0.73029 (13)0.33913 (14)0.0285 (3)
C60.1323 (2)0.86489 (14)0.3400 (2)0.0484 (5)
H6A0.02610.87210.27590.058*
H6B0.13630.88420.42570.058*
C70.15547 (18)1.02977 (13)0.21382 (15)0.0337 (4)
H7A0.04961.01920.16770.040*
C80.22990 (16)1.12861 (13)0.16989 (14)0.0288 (3)
C90.14469 (17)1.19809 (13)0.05954 (14)0.0313 (3)
H9A0.03921.18350.01610.038*
C100.21199 (18)1.28840 (14)0.01229 (15)0.0346 (4)
H10A0.15301.33460.06390.042*
C110.36432 (19)1.31114 (14)0.07569 (15)0.0357 (4)
H11A0.41051.37320.04350.043*
C120.45054 (17)1.24339 (15)0.18669 (15)0.0347 (4)
H12A0.55561.25970.23050.042*
C130.38459 (17)1.15228 (14)0.23412 (14)0.0318 (3)
H13A0.44421.10600.31000.038*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0341 (7)0.0335 (7)0.0304 (7)0.0004 (6)0.0127 (6)0.0025 (5)
N20.0540 (9)0.0231 (6)0.0479 (8)0.0000 (6)0.0305 (7)0.0018 (6)
C10.0507 (10)0.0335 (8)0.0465 (10)0.0098 (8)0.0286 (9)0.0102 (7)
C20.0496 (10)0.0257 (7)0.0796 (14)0.0064 (7)0.0459 (10)0.0101 (8)
C30.0279 (8)0.0498 (10)0.0557 (11)0.0094 (7)0.0207 (8)0.0323 (9)
C40.0339 (8)0.0477 (9)0.0289 (8)0.0082 (7)0.0149 (7)0.0028 (7)
C50.0302 (7)0.0257 (7)0.0336 (8)0.0020 (6)0.0175 (6)0.0015 (6)
C60.0674 (12)0.0283 (8)0.0715 (13)0.0053 (8)0.0509 (11)0.0040 (8)
C70.0371 (8)0.0256 (7)0.0453 (9)0.0014 (6)0.0242 (8)0.0065 (7)
C80.0322 (8)0.0244 (7)0.0343 (8)0.0012 (6)0.0186 (7)0.0064 (6)
C90.0303 (7)0.0293 (7)0.0333 (8)0.0035 (6)0.0125 (6)0.0057 (6)
C100.0416 (9)0.0311 (8)0.0312 (8)0.0049 (7)0.0156 (7)0.0007 (6)
C110.0469 (9)0.0287 (7)0.0397 (9)0.0032 (7)0.0262 (8)0.0040 (7)
C120.0307 (8)0.0356 (8)0.0396 (9)0.0040 (7)0.0168 (7)0.0094 (7)
C130.0343 (8)0.0301 (7)0.0300 (8)0.0033 (6)0.0127 (6)0.0040 (6)
Geometric parameters (Å, º) top
N1—C11.333 (2)C6—H6B0.9900
N1—C51.3391 (18)C7—C81.470 (2)
N2—C71.265 (2)C7—H7A0.9500
N2—C61.467 (2)C8—C91.390 (2)
C1—C21.364 (2)C8—C131.398 (2)
C1—H1A0.9500C9—C101.386 (2)
C2—C31.367 (3)C9—H9A0.9500
C2—H2A0.9500C10—C111.376 (2)
C3—C41.383 (2)C10—H10A0.9500
C3—H3A0.9500C11—C121.387 (2)
C4—C51.381 (2)C11—H11A0.9500
C4—H4A0.9500C12—C131.384 (2)
C5—C61.506 (2)C12—H12A0.9500
C6—H6A0.9900C13—H13A0.9500
C1—N1—C5116.94 (13)H6A—C6—H6B108.1
C7—N2—C6116.07 (15)N2—C7—C8123.50 (15)
N1—C1—C2124.36 (16)N2—C7—H7A118.2
N1—C1—H1A117.8C8—C7—H7A118.2
C2—C1—H1A117.8C9—C8—C13119.14 (13)
C1—C2—C3118.37 (15)C9—C8—C7119.01 (14)
C1—C2—H2A120.8C13—C8—C7121.83 (14)
C3—C2—H2A120.8C10—C9—C8120.66 (14)
C2—C3—C4119.06 (15)C10—C9—H9A119.7
C2—C3—H3A120.5C8—C9—H9A119.7
C4—C3—H3A120.5C11—C10—C9119.97 (15)
C5—C4—C3118.71 (15)C11—C10—H10A120.0
C5—C4—H4A120.6C9—C10—H10A120.0
C3—C4—H4A120.6C10—C11—C12119.99 (14)
N1—C5—C4122.57 (13)C10—C11—H11A120.0
N1—C5—C6115.06 (13)C12—C11—H11A120.0
C4—C5—C6122.37 (14)C13—C12—C11120.49 (14)
N2—C6—C5110.62 (12)C13—C12—H12A119.8
N2—C6—H6A109.5C11—C12—H12A119.8
C5—C6—H6A109.5C12—C13—C8119.75 (14)
N2—C6—H6B109.5C12—C13—H13A120.1
C5—C6—H6B109.5C8—C13—H13A120.1
C5—N1—C1—C20.2 (2)C6—N2—C7—C8179.81 (13)
N1—C1—C2—C30.2 (2)N2—C7—C8—C9176.78 (13)
C1—C2—C3—C40.1 (2)N2—C7—C8—C131.5 (2)
C2—C3—C4—C50.0 (2)C13—C8—C9—C101.0 (2)
C1—N1—C5—C40.1 (2)C7—C8—C9—C10177.39 (12)
C1—N1—C5—C6179.47 (13)C8—C9—C10—C110.8 (2)
C3—C4—C5—N10.0 (2)C9—C10—C11—C120.2 (2)
C3—C4—C5—C6179.50 (14)C10—C11—C12—C130.3 (2)
C7—N2—C6—C5122.53 (16)C11—C12—C13—C80.2 (2)
N1—C5—C6—N274.07 (19)C9—C8—C13—C120.5 (2)
C4—C5—C6—N2106.40 (17)C7—C8—C13—C12177.85 (12)
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of rings C8–C13 and N1/C1–C5, respectively.
D—H···AD—HH···AD···AD—H···A
C2—H2A···Cg1i0.952.873.6655 (19)142
C3—H3A···Cg1ii0.952.713.4436 (19)135
C7—H7A···Cg2iii0.952.933.716 (2)140
C12—H12A···Cg2iv0.952.913.484 (2)120
Symmetry codes: (i) x, y1, z; (ii) x, y+3/2, z+1/2; (iii) x, y+1/2, z+1/2; (iv) x+1, y+1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of rings C8–C13 and N1/C1–C5, respectively.
D—H···AD—HH···AD···AD—H···A
C2—H2A···Cg1i0.952.873.6655 (19)142
C3—H3A···Cg1ii0.952.713.4436 (19)135
C7—H7A···Cg2iii0.952.933.716 (2)140
C12—H12A···Cg2iv0.952.913.484 (2)120
Symmetry codes: (i) x, y1, z; (ii) x, y+3/2, z+1/2; (iii) x, y+1/2, z+1/2; (iv) x+1, y+1/2, z+1/2.
 

Acknowledgements

The authors acknowledge the NSERC Discovery Grant program of Canada and the University of Toronto.

References

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