organic compounds
(E)-N-{3-[(m-Tolylimino)methyl]pyridin-2-yl}pivalamide
aDepartment of Physics, Faculty of Arts and Sciences, Ondokuz Mayıs University, Kurupelit, 55139 Samsun, Turkey, and bDepartment of Chemistry, Faculty of Arts and Sciences, Ondokuz Mayıs University, Kurupelit, 55139 Samsun, Turkey
*Correspondence e-mail: atalays@omu.edu.tr
In the title compound, C18H21N3O, the dihedral angle between the pyridine and benzene rings is 30.53 (7)° and the C—C=N—C torsion angle is −170.6 (2)°. An intramolecular N—H⋯N hydrogen bond generates an S(6) ring. In the crystal, very weak C—H⋯O hydrogen bonds link the molecules into C(8) [101] chains. The tert-butyl methyl groups are disordered over two sets of sites in a 0.783 (4):0.217 (4) ratio.
Keywords: crystal structure; Schiff base; hydrogen bonding.
CCDC reference: 1587716
Structure description
. As part of our studies in this area, we herein report the synthesis and structure of the title compound (Fig. 1).
were first reported by Hugo Schiff in 1864The dihedral angle between the pyridine (N2/C9–C13) and benzene (C2–C7) ring systems is 30.53 (7)°. The molecular structure features an intramolecular N—H⋯N hydrogen bond, which generates an S(6) ring. The C—N bond distances of the imino-group atoms [C6—N1 = 1.420 (3) Å and C8=N1 = 1.273 (3) Å] are consistent with those in related structures such as 2,4-dichloro-N-[(E)-(5-nitrothiophen-2-yl) methylidene]aniline (Köysal et al., 2016).
In the crystal, weak C11—H11⋯O1 hydrogen bonds (Table 1, Fig. 2) link the molecules into [101] chains.
Synthesis and crystallization
Solutions of N-(5-formylpyridin-2-yl)pivalamide (0.020 g, 0.96 mmol) in 20 ml ethanol and o-toluidine (0.0107 g, 0.90 mmol) in 20 ml ethanol were mixed and stirred for 1 h under reflux. Colourless needles were recovered upon slow evaporation of the solvent (yield 60%; m.p 457–459 K).
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2Structural data
CCDC reference: 1587716
https://doi.org/10.1107/S2414314617017023/hb4184sup1.cif
contains datablocks seh24, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617017023/hb4184Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314617017023/hb4184Isup3.cml
Data collection: X-AREA (Stoe & Cie, 2002); cell
X-AREA (Stoe & Cie, 2002); data reduction: X-RED32 (Stoe & Cie, 2002); program(s) used to solve structure: SHELXT2016/6 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2016/6 (Sheldrick, 2015b); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).C18H21N3O | F(000) = 632 |
Mr = 295.38 | Dx = 1.202 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 5.572 (3) Å | Cell parameters from 16183 reflections |
b = 24.9671 (11) Å | θ = 1.6–26.5° |
c = 12.2380 (5) Å | µ = 0.08 mm−1 |
β = 106.529 (3)° | T = 293 K |
V = 1632.1 (7) Å3 | Needle, colorless |
Z = 4 | 0.51 × 0.21 × 0.01 mm |
STOE IPDS 2 diffractometer | 2957 independent reflections |
Radiation source: sealed X-ray tube, 12 x 0.4 mm long-fine focus | 1820 reflections with I > 2σ(I) |
Detector resolution: 6.67 pixels mm-1 | Rint = 0.088 |
w scans | θmax = 25.3°, θmin = 1.6° |
Absorption correction: integration X-RED32 (Stoe & Cie, 2002) | h = −6→6 |
Tmin = 0.969, Tmax = 0.993 | k = −29→29 |
19913 measured reflections | l = −14→14 |
Refinement on F2 | 127 restraints |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.060 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.151 | w = 1/[σ2(Fo2) + (0.0694P)2 + 0.1577P] where P = (Fo2 + 2Fc2)/3 |
S = 1.02 | (Δ/σ)max < 0.001 |
2957 reflections | Δρmax = 0.21 e Å−3 |
237 parameters | Δρmin = −0.24 e Å−3 |
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. |
Refinement. The H3 and H11 atoms bonded to N3 and C11 were freely refined. All other H atoms were positioned geometrically and rifined using a riding model, with C—H distances of 0.93 Å and methyl C—H distances 0.96 Å. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
O1 | 0.0148 (4) | 0.34395 (8) | 0.93073 (15) | 0.0765 (7) | |
N1 | 0.0847 (4) | 0.33938 (9) | 0.53592 (17) | 0.0543 (6) | |
N2 | −0.3301 (4) | 0.28489 (9) | 0.76396 (18) | 0.0582 (6) | |
N3 | −0.0212 (5) | 0.34425 (9) | 0.74136 (19) | 0.0563 (6) | |
C1 | 0.7176 (6) | 0.45364 (12) | 0.4428 (3) | 0.0762 (9) | |
H1A | 0.661209 | 0.489716 | 0.447020 | 0.114* | |
H1B | 0.814125 | 0.451961 | 0.389229 | 0.114* | |
H1C | 0.819411 | 0.442612 | 0.516564 | 0.114* | |
C2 | 0.4947 (5) | 0.41701 (11) | 0.4044 (2) | 0.0596 (7) | |
C3 | 0.3744 (7) | 0.40961 (13) | 0.2903 (3) | 0.0732 (9) | |
H3A | 0.436555 | 0.426282 | 0.235999 | 0.088* | |
C4 | 0.1643 (7) | 0.37802 (13) | 0.2552 (2) | 0.0734 (9) | |
H4A | 0.086189 | 0.373619 | 0.177745 | 0.088* | |
C5 | 0.0679 (6) | 0.35273 (11) | 0.3341 (2) | 0.0625 (7) | |
H5 | −0.074962 | 0.331639 | 0.309921 | 0.075* | |
C6 | 0.1859 (5) | 0.35905 (10) | 0.4495 (2) | 0.0533 (7) | |
C7 | 0.3986 (5) | 0.39123 (11) | 0.4825 (2) | 0.0572 (7) | |
H7 | 0.478515 | 0.395498 | 0.559810 | 0.069* | |
C8 | −0.0425 (5) | 0.29625 (11) | 0.5208 (2) | 0.0560 (7) | |
H8 | −0.045267 | 0.275629 | 0.457161 | 0.067* | |
C9 | −0.1845 (5) | 0.27694 (10) | 0.5967 (2) | 0.0516 (6) | |
C10 | −0.3483 (6) | 0.23469 (11) | 0.5595 (2) | 0.0612 (8) | |
H10 | −0.354012 | 0.217390 | 0.491512 | 0.073* | |
C11 | −0.5023 (6) | 0.21830 (12) | 0.6229 (2) | 0.0659 (8) | |
H11 | −0.614229 | 0.190184 | 0.598442 | 0.079* | |
C12 | −0.4870 (5) | 0.24440 (11) | 0.7229 (2) | 0.0631 (8) | |
H12 | −0.592703 | 0.233252 | 0.765170 | 0.076* | |
C13 | −0.1813 (5) | 0.30095 (9) | 0.7022 (2) | 0.0491 (6) | |
C14 | 0.0607 (5) | 0.36424 (10) | 0.8489 (2) | 0.0525 (6) | |
C15 | 0.2151 (5) | 0.41602 (10) | 0.8613 (2) | 0.0571 (7) | |
C16A | 0.0395 (9) | 0.46332 (15) | 0.8459 (7) | 0.1140 (19) | 0.783 (4) |
H16A | 0.129858 | 0.495653 | 0.841931 | 0.171* | 0.783 (4) |
H16B | −0.029205 | 0.465312 | 0.909403 | 0.171* | 0.783 (4) |
H16C | −0.093634 | 0.459038 | 0.776741 | 0.171* | 0.783 (4) |
C17A | 0.4209 (10) | 0.4148 (2) | 0.9742 (4) | 0.115 (2) | 0.783 (4) |
H17A | 0.522650 | 0.383497 | 0.977020 | 0.172* | 0.783 (4) |
H17B | 0.346685 | 0.413798 | 1.036013 | 0.172* | 0.783 (4) |
H17C | 0.522916 | 0.446261 | 0.980700 | 0.172* | 0.783 (4) |
C18A | 0.3581 (8) | 0.42136 (18) | 0.7721 (4) | 0.0810 (13) | 0.783 (4) |
H18A | 0.464112 | 0.452371 | 0.788654 | 0.122* | 0.783 (4) |
H18B | 0.241203 | 0.425071 | 0.697804 | 0.122* | 0.783 (4) |
H18C | 0.458626 | 0.389982 | 0.773700 | 0.122* | 0.783 (4) |
C16B | 0.090 (3) | 0.4532 (5) | 0.7612 (13) | 0.094 (4) | 0.217 (4) |
H16D | −0.077479 | 0.461039 | 0.762392 | 0.141* | 0.217 (4) |
H16E | 0.184157 | 0.485869 | 0.767965 | 0.141* | 0.217 (4) |
H16F | 0.086620 | 0.435823 | 0.690736 | 0.141* | 0.217 (4) |
C17B | 0.171 (4) | 0.4469 (5) | 0.9637 (13) | 0.088 (4) | 0.217 (4) |
H17D | 0.227235 | 0.483230 | 0.962648 | 0.132* | 0.217 (4) |
H17E | 0.263494 | 0.430012 | 1.033458 | 0.132* | 0.217 (4) |
H17F | −0.003913 | 0.446646 | 0.958390 | 0.132* | 0.217 (4) |
C18B | 0.4808 (15) | 0.4025 (5) | 0.8628 (18) | 0.101 (4) | 0.217 (4) |
H18D | 0.488336 | 0.365988 | 0.839495 | 0.151* | 0.217 (4) |
H18E | 0.589883 | 0.407175 | 0.938581 | 0.151* | 0.217 (4) |
H18F | 0.532814 | 0.425795 | 0.811415 | 0.151* | 0.217 (4) |
H3 | 0.044 (5) | 0.3550 (11) | 0.690 (2) | 0.062 (8)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0948 (16) | 0.0850 (14) | 0.0462 (11) | −0.0347 (12) | 0.0143 (10) | 0.0012 (10) |
N1 | 0.0632 (15) | 0.0538 (14) | 0.0484 (12) | −0.0040 (12) | 0.0196 (11) | −0.0008 (10) |
N2 | 0.0647 (15) | 0.0543 (13) | 0.0571 (13) | −0.0130 (12) | 0.0200 (11) | −0.0020 (10) |
N3 | 0.0737 (16) | 0.0524 (13) | 0.0455 (12) | −0.0199 (12) | 0.0214 (11) | −0.0067 (10) |
C1 | 0.079 (2) | 0.068 (2) | 0.091 (2) | 0.0003 (17) | 0.0400 (18) | 0.0070 (16) |
C2 | 0.0664 (19) | 0.0541 (16) | 0.0658 (18) | 0.0112 (14) | 0.0309 (15) | 0.0055 (13) |
C3 | 0.095 (3) | 0.073 (2) | 0.0622 (19) | 0.0041 (19) | 0.0403 (18) | 0.0064 (15) |
C4 | 0.097 (2) | 0.080 (2) | 0.0483 (16) | 0.007 (2) | 0.0279 (16) | 0.0018 (15) |
C5 | 0.0720 (19) | 0.0660 (17) | 0.0506 (16) | 0.0018 (15) | 0.0191 (14) | −0.0040 (13) |
C6 | 0.0647 (17) | 0.0504 (15) | 0.0492 (15) | 0.0058 (14) | 0.0233 (13) | 0.0014 (12) |
C7 | 0.0660 (18) | 0.0557 (16) | 0.0523 (15) | 0.0079 (14) | 0.0208 (14) | 0.0042 (12) |
C8 | 0.0698 (19) | 0.0518 (16) | 0.0450 (14) | 0.0023 (14) | 0.0142 (13) | −0.0038 (12) |
C9 | 0.0598 (17) | 0.0430 (14) | 0.0482 (14) | 0.0008 (12) | 0.0095 (12) | −0.0009 (11) |
C10 | 0.078 (2) | 0.0486 (16) | 0.0513 (15) | −0.0087 (14) | 0.0096 (14) | −0.0065 (12) |
C11 | 0.070 (2) | 0.0563 (17) | 0.0643 (18) | −0.0137 (15) | 0.0085 (15) | −0.0027 (14) |
C12 | 0.0618 (18) | 0.0599 (17) | 0.0679 (18) | −0.0120 (15) | 0.0189 (15) | 0.0008 (14) |
C13 | 0.0560 (16) | 0.0448 (14) | 0.0447 (13) | −0.0033 (12) | 0.0113 (12) | 0.0027 (11) |
C14 | 0.0636 (17) | 0.0497 (14) | 0.0432 (14) | −0.0042 (12) | 0.0136 (12) | 0.0010 (11) |
C15 | 0.0727 (18) | 0.0482 (14) | 0.0516 (14) | −0.0143 (13) | 0.0195 (13) | −0.0057 (11) |
C16A | 0.096 (3) | 0.066 (3) | 0.192 (6) | −0.004 (2) | 0.059 (4) | −0.023 (3) |
C17A | 0.134 (4) | 0.115 (4) | 0.069 (3) | −0.072 (3) | −0.015 (3) | 0.010 (3) |
C18A | 0.080 (3) | 0.082 (3) | 0.086 (3) | −0.035 (2) | 0.032 (2) | −0.012 (2) |
C16B | 0.121 (8) | 0.050 (6) | 0.102 (7) | −0.023 (6) | 0.015 (7) | 0.004 (6) |
C17B | 0.121 (8) | 0.066 (7) | 0.090 (6) | −0.053 (7) | 0.049 (6) | −0.034 (5) |
C18B | 0.088 (6) | 0.106 (8) | 0.107 (9) | −0.022 (6) | 0.025 (6) | −0.012 (7) |
O1—C14 | 1.213 (3) | C11—C12 | 1.368 (4) |
N1—C8 | 1.273 (3) | C11—H11 | 0.9300 |
N1—C6 | 1.420 (3) | C12—H12 | 0.9300 |
N2—C13 | 1.333 (3) | C14—C15 | 1.536 (4) |
N2—C12 | 1.338 (3) | C15—C16A | 1.511 (4) |
N3—C14 | 1.359 (3) | C15—C18B | 1.513 (7) |
N3—C13 | 1.397 (3) | C15—C17A | 1.524 (4) |
N3—H3 | 0.86 (3) | C15—C18A | 1.530 (4) |
C1—C2 | 1.506 (4) | C15—C16B | 1.536 (7) |
C1—H1A | 0.9600 | C15—C17B | 1.549 (6) |
C1—H1B | 0.9600 | C16A—H16A | 0.9600 |
C1—H1C | 0.9600 | C16A—H16B | 0.9600 |
C2—C3 | 1.380 (4) | C16A—H16C | 0.9600 |
C2—C7 | 1.380 (4) | C17A—H17A | 0.9600 |
C3—C4 | 1.375 (4) | C17A—H17B | 0.9600 |
C3—H3A | 0.9300 | C17A—H17C | 0.9600 |
C4—C5 | 1.384 (4) | C18A—H18A | 0.9600 |
C4—H4A | 0.9300 | C18A—H18B | 0.9600 |
C5—C6 | 1.387 (4) | C18A—H18C | 0.9600 |
C5—H5 | 0.9300 | C16B—H16D | 0.9600 |
C6—C7 | 1.393 (4) | C16B—H16E | 0.9600 |
C7—H7 | 0.9300 | C16B—H16F | 0.9600 |
C8—C9 | 1.462 (4) | C17B—H17D | 0.9600 |
C8—H8 | 0.9300 | C17B—H17E | 0.9600 |
C9—C10 | 1.384 (4) | C17B—H17F | 0.9600 |
C9—C13 | 1.419 (3) | C18B—H18D | 0.9600 |
C10—C11 | 1.373 (4) | C18B—H18E | 0.9600 |
C10—H10 | 0.9300 | C18B—H18F | 0.9600 |
C8—N1—C6 | 120.4 (2) | N3—C14—C15 | 115.4 (2) |
C13—N2—C12 | 117.4 (2) | C16A—C15—C17A | 115.0 (4) |
C14—N3—C13 | 128.5 (2) | C16A—C15—C18A | 107.1 (4) |
C14—N3—H3 | 120.2 (19) | C17A—C15—C18A | 103.8 (3) |
C13—N3—H3 | 110.7 (18) | C18B—C15—C16B | 111.3 (11) |
C2—C1—H1A | 109.5 | C16A—C15—C14 | 108.7 (3) |
C2—C1—H1B | 109.5 | C18B—C15—C14 | 109.4 (5) |
H1A—C1—H1B | 109.5 | C17A—C15—C14 | 109.1 (2) |
C2—C1—H1C | 109.5 | C18A—C15—C14 | 113.2 (2) |
H1A—C1—H1C | 109.5 | C16B—C15—C14 | 108.4 (5) |
H1B—C1—H1C | 109.5 | C18B—C15—C17B | 118.7 (10) |
C3—C2—C7 | 117.8 (3) | C16B—C15—C17B | 101.8 (11) |
C3—C2—C1 | 121.1 (3) | C14—C15—C17B | 106.6 (4) |
C7—C2—C1 | 121.0 (3) | C15—C16A—H16A | 109.5 |
C4—C3—C2 | 121.2 (3) | C15—C16A—H16B | 109.5 |
C4—C3—H3A | 119.4 | H16A—C16A—H16B | 109.5 |
C2—C3—H3A | 119.4 | C15—C16A—H16C | 109.5 |
C3—C4—C5 | 120.6 (3) | H16A—C16A—H16C | 109.5 |
C3—C4—H4A | 119.7 | H16B—C16A—H16C | 109.5 |
C5—C4—H4A | 119.7 | C15—C17A—H17A | 109.5 |
C4—C5—C6 | 119.6 (3) | C15—C17A—H17B | 109.5 |
C4—C5—H5 | 120.2 | H17A—C17A—H17B | 109.5 |
C6—C5—H5 | 120.2 | C15—C17A—H17C | 109.5 |
C5—C6—C7 | 118.6 (2) | H17A—C17A—H17C | 109.5 |
C5—C6—N1 | 123.0 (3) | H17B—C17A—H17C | 109.5 |
C7—C6—N1 | 118.0 (2) | C15—C18A—H18A | 109.5 |
C2—C7—C6 | 122.3 (3) | C15—C18A—H18B | 109.5 |
C2—C7—H7 | 118.9 | H18A—C18A—H18B | 109.5 |
C6—C7—H7 | 118.9 | C15—C18A—H18C | 109.5 |
N1—C8—C9 | 124.5 (2) | H18A—C18A—H18C | 109.5 |
N1—C8—H8 | 117.8 | H18B—C18A—H18C | 109.5 |
C9—C8—H8 | 117.8 | C15—C16B—H16D | 109.5 |
C10—C9—C13 | 117.2 (2) | C15—C16B—H16E | 109.5 |
C10—C9—C8 | 117.9 (2) | H16D—C16B—H16E | 109.5 |
C13—C9—C8 | 124.7 (2) | C15—C16B—H16F | 109.5 |
C11—C10—C9 | 120.1 (3) | H16D—C16B—H16F | 109.5 |
C11—C10—H10 | 120.0 | H16E—C16B—H16F | 109.5 |
C9—C10—H10 | 120.0 | C15—C17B—H17D | 109.5 |
C12—C11—C10 | 118.3 (3) | C15—C17B—H17E | 109.5 |
C12—C11—H11 | 120.9 | H17D—C17B—H17E | 109.5 |
C10—C11—H11 | 120.9 | C15—C17B—H17F | 109.5 |
N2—C12—C11 | 124.3 (3) | H17D—C17B—H17F | 109.5 |
N2—C12—H12 | 117.8 | H17E—C17B—H17F | 109.5 |
C11—C12—H12 | 117.8 | C15—C18B—H18D | 109.5 |
N2—C13—N3 | 118.5 (2) | C15—C18B—H18E | 109.5 |
N2—C13—C9 | 122.7 (2) | H18D—C18B—H18E | 109.5 |
N3—C13—C9 | 118.7 (2) | C15—C18B—H18F | 109.5 |
O1—C14—N3 | 123.7 (2) | H18D—C18B—H18F | 109.5 |
O1—C14—C15 | 120.9 (2) | H18E—C18B—H18F | 109.5 |
C7—C2—C3—C4 | 0.6 (4) | C12—N2—C13—C9 | 0.0 (4) |
C1—C2—C3—C4 | −177.1 (3) | C14—N3—C13—N2 | 20.5 (4) |
C2—C3—C4—C5 | 0.0 (5) | C14—N3—C13—C9 | −161.5 (3) |
C3—C4—C5—C6 | −0.5 (4) | C10—C9—C13—N2 | −1.0 (4) |
C4—C5—C6—C7 | 0.4 (4) | C8—C9—C13—N2 | 174.0 (2) |
C4—C5—C6—N1 | 172.9 (3) | C10—C9—C13—N3 | −179.0 (2) |
C8—N1—C6—C5 | 33.4 (4) | C8—C9—C13—N3 | −4.0 (4) |
C8—N1—C6—C7 | −154.0 (3) | C13—N3—C14—O1 | 4.9 (5) |
C3—C2—C7—C6 | −0.7 (4) | C13—N3—C14—C15 | −174.0 (2) |
C1—C2—C7—C6 | 177.0 (2) | O1—C14—C15—C16A | −88.8 (4) |
C5—C6—C7—C2 | 0.2 (4) | N3—C14—C15—C16A | 90.1 (4) |
N1—C6—C7—C2 | −172.7 (2) | O1—C14—C15—C18B | 101.5 (9) |
C6—N1—C8—C9 | −170.6 (2) | N3—C14—C15—C18B | −79.6 (9) |
N1—C8—C9—C10 | 168.9 (3) | O1—C14—C15—C17A | 37.3 (4) |
N1—C8—C9—C13 | −6.0 (4) | N3—C14—C15—C17A | −143.8 (4) |
C13—C9—C10—C11 | 1.2 (4) | O1—C14—C15—C18A | 152.4 (3) |
C8—C9—C10—C11 | −174.1 (3) | N3—C14—C15—C18A | −28.7 (4) |
C9—C10—C11—C12 | −0.6 (4) | O1—C14—C15—C16B | −136.9 (10) |
C13—N2—C12—C11 | 0.7 (4) | N3—C14—C15—C16B | 42.0 (10) |
C10—C11—C12—N2 | −0.4 (4) | O1—C14—C15—C17B | −28.0 (10) |
C12—N2—C13—N3 | 178.0 (2) | N3—C14—C15—C17B | 150.9 (9) |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3···N1 | 0.86 (3) | 2.00 (3) | 2.744 (3) | 145 (3) |
C11—H11···O1i | 0.93 | 2.61 | 3.404 (4) | 144 |
Symmetry code: (i) x−1, −y+1/2, z−1/2. |
Acknowledgements
The authors wish to acknowledge the Faculty of Arts and Sciences, Ondokuz Mayıs University, Turkey, for the use of the Stoe IPDS II diffractometer(purchased under grant F.279 of the University Research Fund).
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