(6E)-N-[(4Z)-2,5-Dimethyl-4-(p-tolyl­imino)cyclo­hexa-2,5-dienyl­idene]-4-methyl­aniline

Abstract

The title compound, C₂₂H₂₂N₂, was prepared by the reaction of 4-amino­toluene with sodium carbonate, sodium hydroxide and potassium permanganate. The mol­ecule is disposed about a crystallographic inversion centre with one half-mol­ecule comprising the asymmetric unit. The dihedral angle between the terminal and central benzene rings is 88.05 (1)°. The crystal packing is stabilized by van der Waals forces.

Related literature

For related literature, see: Boyer et al. (2000 ▶); Hadek (1968 ▶); Hadek et al. (1969 ▶)

Experimental

Crystal data

• C₂₂H₂₂N₂

• M _r = 314.42

• Trigonal,

• a = 21.173 (8) Å

• c = 10.476 (2) Å

• V = 4067 (2) ų

• Z = 9

• Mo Kα radiation

• μ = 0.07 mm⁻¹

• T = 293 (2) K

• 0.21 × 0.18 × 0.15 mm

Data collection

• Enraf–Nonius CAD-4 diffractometer

• Absorption correction: none

• 6148 measured reflections

• 1956 independent reflections

• 793 reflections with I > 2σ(I)

• R _int = 0.075

• 3 standard reflections every 100 reflections intensity decay: none

Refinement

• R[F ² > 2σ(F ²)] = 0.072

• wR(F ²) = 0.233

• S = 1.02

• 1956 reflections

• 110 parameters

• H-atom parameters constrained

• Δρ_max = 0.19 e Å⁻³

• Δρ_min = −0.14 e Å⁻³

Data collection: CAD-4 Software (Enraf–Nonius, 1989 ▶); cell refinement: CAD-4 Software; data reduction: NRCVAX (Gabe et al., 1989 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997 ▶); molecular graphics: SHELXTL/PC (Sheldrick, 1990 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Comment

It is now well established that conformational characteristics of the polyaniline polymer play a crucial role for its physical properties, including transport characteristics (Boyer et al., 2000). Detailed analysis of the crystal structures of polyaniline oligomers containing alternating benzoid and quinoid rings with amine and/or imine groups can help in the understanding of the spectroscopic behaviour of the compounds and possibles mechanism for their electrical conductivity (Hadek,1968; Hadek et al., 1969). Here we report the crystal structure of the title compound, (I).

The structure of (I) consists of discrete molecules disposed about a crystallographic inversion centre with half the molecule comprising the asymmetric unit (Fig. 1). The atoms (N1, C1 - C7) are planar with the greatest deviation from planarity for N1 of 0.042 (1) Å). The bond lengths and angles are usual for this type of compound (Boyer et al., 2000). The mean planes p1(C2 - C7) and p2(C8 - C10,C8a - C10a) make a dihedral angle of 88.06 (1)°. The dihedral angle formed by ring (N1,C1 - C7)and ring (N1,C5 - C11,N1a,C5a) is 1.52 (1)°. The crystal packing (Fig.2) is stabilized by van der Waals forces.

Experimental

P-aminotoluene (2.14 g, 0.02 mol) was dissolved in water (100 ml), then sodium carbonate (0.53 g, 0.005 mol), sodium hydroxide (0.80 g, 0.02 mol) and potassium permanganate (1.58 g, 0.01 mol) was added with stirring. The mixture was allowed to react at room temperature for 12 h to give a precipitate which wasfiltered and recrystallized from acetone to afford the title compound (0.956 g, yield 89.5%). Single crystals suitable for X-ray measurements were obtained by recrystallization from acetone at room temperature.

Refinement

H atoms were fixed geometrically and allowed to ride on their parent atoms, with C—H distances of 0.93–0.96 Å and with U_iso=1.2–1.5 U_eq of the parent atoms.

Figures

Fig. 1.

The molecular structure and atom-labeling scheme for (I), with displacement ellipsoids drawn at the 30% probability level. 'A' atoms were generated by symmetry (-x + 1/3, -y + 2/3, -z - 1/3).

Fig. 2.

The crystal packing of (I),viewed down the c axis.

Crystal data

C22H22N2	Z = 9
Mr = 314.42	F000 = 1512
Trigonal, R3	Dx = 1.155 Mg m−3
Hall symbol: -R 3	Mo Kα radiation λ = 0.71073 Å
a = 21.173 (8) Å	Cell parameters from 25 reflections
b = 21.173 (8) Å	θ = 4–14º
c = 10.476 (2) Å	µ = 0.07 mm−1
α = 90º	T = 293 (2) K
β = 90º	Block, red
γ = 120º	0.21 × 0.18 × 0.15 mm
V = 4067 (2) Å3

Data collection

Enraf–Nonius CAD-4 diffractometer	Rint = 0.075
Radiation source: fine-focus sealed tube	θmax = 27.0º
Monochromator: graphite	θmin = 1.9º
T = 293(2) K	h = −26→26
ω scans	k = −26→26
Absorption correction: none	l = −12→0
6148 measured reflections	3 standard reflections
1956 independent reflections	every 100 reflections
793 reflections with I > 2σ(I)	intensity decay: none

Refinement

Refinement on F2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F2 > 2σ(F2)] = 0.072	w = 1/[σ2(Fo2) + (0.1023P)2 + 1.7438P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.233	(Δ/σ)max < 0.001
S = 1.02	Δρmax = 0.19 e Å−3
1956 reflections	Δρmin = −0.14 e Å−3
110 parameters	Extinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0029 (9)
Secondary atom site location: difference Fourier map

Special details

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.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
N1	0.17771 (14)	0.28153 (14)	0.0673 (3)	0.0845 (9)
C1	−0.0660 (2)	0.1028 (3)	0.3942 (4)	0.1275 (17)
H1B	−0.0769	0.1330	0.4474	0.191*
H1C	−0.0529	0.0740	0.4468	0.191*
H1D	−0.1081	0.0712	0.3441	0.191*
C2	−0.00306 (19)	0.1504 (2)	0.3064 (3)	0.0882 (11)
C3	0.0232 (2)	0.1207 (2)	0.2204 (5)	0.1262 (16)
H3A	0.0010	0.0702	0.2149	0.151*
C4	0.0822 (2)	0.1636 (2)	0.1401 (5)	0.1197 (15)
H4A	0.0988	0.1413	0.0836	0.144*
C5	0.11505 (18)	0.23690 (19)	0.1441 (3)	0.0743 (9)
C6	0.0891 (2)	0.2665 (2)	0.2299 (4)	0.1182 (15)
H6A	0.1111	0.3170	0.2358	0.142*
C7	0.0306 (3)	0.2232 (3)	0.3089 (4)	0.1189 (15)
H7A	0.0141	0.2456	0.3656	0.143*
C8	0.10079 (16)	0.28723 (16)	−0.1018 (3)	0.0740 (9)
H8A	0.0579	0.2564	−0.0583	0.089*
C9	0.16973 (16)	0.30428 (16)	−0.0440 (3)	0.0707 (9)
C10	0.23710 (16)	0.35227 (17)	−0.1164 (3)	0.0730 (9)
C11	0.30536 (15)	0.36974 (17)	−0.0619 (3)	0.0810 (10)
H11A	0.3439	0.4007	−0.1192	0.122*
H11B	0.3068	0.3257	−0.0474	0.122*
H11C	0.3115	0.3946	0.0178	0.122*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
N1	0.0729 (18)	0.093 (2)	0.092 (2)	0.0442 (16)	−0.0040 (15)	0.0096 (17)
C1	0.103 (3)	0.172 (4)	0.109 (3)	0.070 (3)	0.021 (3)	0.052 (3)
C2	0.082 (2)	0.112 (3)	0.081 (2)	0.055 (2)	−0.003 (2)	0.018 (2)
C3	0.105 (3)	0.081 (3)	0.179 (4)	0.036 (2)	0.031 (3)	0.017 (3)
C4	0.111 (3)	0.089 (3)	0.150 (4)	0.043 (3)	0.028 (3)	−0.012 (3)
C5	0.071 (2)	0.078 (2)	0.081 (2)	0.0428 (19)	−0.0086 (18)	0.0033 (19)
C6	0.139 (4)	0.081 (3)	0.140 (4)	0.059 (3)	0.036 (3)	0.006 (3)
C7	0.142 (4)	0.104 (3)	0.115 (3)	0.064 (3)	0.043 (3)	0.011 (3)
C8	0.0603 (19)	0.075 (2)	0.090 (2)	0.0369 (16)	0.0000 (17)	0.0017 (18)
C9	0.070 (2)	0.068 (2)	0.082 (2)	0.0400 (17)	−0.0039 (18)	−0.0034 (17)
C10	0.065 (2)	0.074 (2)	0.086 (2)	0.0388 (17)	−0.0052 (17)	−0.0016 (17)
C11	0.0528 (18)	0.093 (2)	0.097 (2)	0.0360 (17)	0.0036 (17)	0.0140 (19)

Geometric parameters (Å, °)

N1—C9	1.305 (4)	C6—C7	1.388 (5)
N1—C5	1.430 (4)	C6—H6A	0.9300
C1—C2	1.516 (5)	C7—H7A	0.9300
C1—H1B	0.9600	C8—C10i	1.360 (4)
C1—H1C	0.9600	C8—C9	1.449 (4)
C1—H1D	0.9600	C8—H8A	0.9300
C2—C7	1.336 (5)	C9—C10	1.481 (4)
C2—C3	1.365 (5)	C10—C8i	1.360 (4)
C3—C4	1.399 (6)	C10—C11	1.420 (4)
C3—H3A	0.9300	C11—H11A	0.9600
C4—C5	1.347 (5)	C11—H11B	0.9600
C4—H4A	0.9300	C11—H11C	0.9600
C5—C6	1.359 (5)
C9—N1—C5	119.9 (3)	C5—C6—H6A	119.2
C2—C1—H1B	109.5	C7—C6—H6A	119.2
C2—C1—H1C	109.5	C2—C7—C6	122.4 (4)
H1B—C1—H1C	109.5	C2—C7—H7A	118.8
C2—C1—H1D	109.5	C6—C7—H7A	118.8
H1B—C1—H1D	109.5	C10i—C8—C9	122.7 (3)
H1C—C1—H1D	109.5	C10i—C8—H8A	118.6
C7—C2—C3	116.0 (4)	C9—C8—H8A	118.6
C7—C2—C1	122.6 (4)	N1—C9—C8	125.6 (3)
C3—C2—C1	121.3 (4)	N1—C9—C10	116.9 (3)
C2—C3—C4	122.3 (4)	C8—C9—C10	117.5 (3)
C2—C3—H3A	118.8	C8i—C10—C11	121.6 (3)
C4—C3—H3A	118.8	C8i—C10—C9	119.8 (3)
C5—C4—C3	120.6 (4)	C11—C10—C9	118.6 (3)
C5—C4—H4A	119.7	C10—C11—H11A	109.5
C3—C4—H4A	119.7	C10—C11—H11B	109.5
C4—C5—C6	117.2 (4)	H11A—C11—H11B	109.5
C4—C5—N1	121.2 (3)	C10—C11—H11C	109.5
C6—C5—N1	121.5 (3)	H11A—C11—H11C	109.5
C5—C6—C7	121.5 (4)	H11B—C11—H11C	109.5

Symmetry codes: (i) −x+1/3, −y+2/3, −z−1/3.