N-[(E)-3,4-Dimeth­oxy­benzyl­idene]-2,3-dimethyl­aniline

Tahir, M.N.; Tariq, M.I.; Tariq, R.H.

doi:10.1107/S1600536811032892

organic compounds

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ISSN: 2056-9890

Volume 67| Part 9| September 2011| Page o2378

doi:10.1107/S1600536811032892

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N-[(E)-3,4-Dimethoxybenzylidene]-2,3-dimethylaniline

M. Nawaz Tahir,^a ^* Muhammad Ilyas Tariq ^b and Riaz H. Tariq ^c

^aDepartment of Physics, University of Sargodha, Sargodha, Pakistan, ^bDepartment of Chemistry, University of Sargodha, Sargodha, Pakistan, and ^cInstitute of Chemical and Pharmaceutical Sciences, The University of Faisalabad, Faisalabad, Pakistan
^*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 11 August 2011; accepted 13 August 2011; online 27 August 2011)

In the title compound, C₁₇H₁₉NO₂, the aromatic rings are oriented at a dihedral angle of 59.27 (12)°. In the crystal, inversion dimers linked by pairs of weak C—H⋯O interactions generate R₂²(12) loops.

Related literature

For related structures, see: Sarfraz et al. (2010 ); Tahir et al. (2010a ,b ); Tariq et al. (2010 ).

Experimental

Crystal data

C₁₇H₁₉NO₂
M_r = 269.33
Triclinic, $[P \overline 1]$
a = 7.0144 (4) Å
b = 7.4488 (4) Å
c = 15.6202 (8) Å
α = 81.987 (2)°
β = 81.009 (3)°
γ = 73.527 (2)°
V = 769.12 (7) Å³
Z = 2
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 296 K
0.34 × 0.25 × 0.22 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.972, T_max = 0.983
8993 measured reflections
3688 independent reflections
2028 reflections with I > 2σ(I)
R_int = 0.019

Refinement

R[F² > 2σ(F²)] = 0.061
wR(F²) = 0.211
S = 1.08
3688 reflections
185 parameters
H-atom parameters constrained
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.18 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C16—H16B⋯O2ⁱ	0.96	2.51	3.454 (3)	167
Symmetry code: (i) -x+1, -y+3, -z.

Data collection: APEX2 (Bruker, 2009 ); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ) and PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811032892/hb6358sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811032892/hb6358Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811032892/hb6358Isup3.cml

checkCIF report

Comment top

We have reported crystal structures of Schiff bases containining 2,3-dimethylaniline moiety i.e. (II) N-[(E)-4-chlorobenzylidene] -2,3-dimethylaniline (Tahir et al., 2010a), (III) i.e., 2-[(E)-(2,3-dimethylphenyl)iminomethyl]phenol (Tahir et al., 2010b), (IV) i.e., N-{(E)-[4-(dimethylamino)phenyl] methylidene}-2,3-dimethylaniline (Sarfraz et al., 2010) and (V) i.e., (2Z)-2-[(2,3-dimethylphenyl)imino]-1,2-diphenylethanone (Tariq et al., 2010). The title compound (I), (Fig. 1) is in continuation to synthesize various compounds of 2,3-dimethylaniline.

In (I), the group A (C1—C8/N1) of 2,3-dimethylaniline and the group B (C9—C17/O1/O2) of 3,4-dimethoxybenzaldehyde are close to planar with r.m.s. deviations of 0.010 and 0.041 Å, respectively. The dihedral angle between A/B is 60.57 (4)°. The molecules are linked in the form of dimers due to inter-molecular hydrogen bonds of C—H···O type with R₂²(12) ring motif (Table 1, Fig. 2). There does not exist any kind of significant π-interactions.

Related literature top

For related structures, see: Sarfraz et al. (2010); Tahir et al. (2010a,b); Tariq et al. (2010).

Experimental top

Equimolar quantities of 2,3-dimethylaniline and 3,4-dimethoxybenzaldehyde were refluxed in methanol for 30 min. The solution was kept at room temperature which affoarded colorless prisms after 48 h.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top

	Fig. 1. View of (I) with displacement ellipsoids drawn at the 50% probability level.
	Fig. 2. The partial packing of (I) showing that molecules form inversion dimers. The dotted lines represent the H-bondings.

N-[(E)-3,4-Dimethoxybenzylidene]-2,3-dimethylaniline top

Crystal data top

C₁₇H₁₉NO₂	Z = 2
M_r = 269.33	F(000) = 288
Triclinic, P1	D_x = 1.163 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.0144 (4) Å	Cell parameters from 2028 reflections
b = 7.4488 (4) Å	θ = 2.7–28.4°
c = 15.6202 (8) Å	µ = 0.08 mm⁻¹
α = 81.987 (2)°	T = 296 K
β = 81.009 (3)°	Prism, colorless
γ = 73.527 (2)°	0.34 × 0.25 × 0.22 mm
V = 769.12 (7) Å³

Data collection top

Bruker Kappa APEXII CCD diffractometer	3688 independent reflections
Radiation source: fine-focus sealed tube	2028 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.019
Detector resolution: 7.50 pixels mm^-1	θ_max = 28.4°, θ_min = 2.7°
ω scans	h = −9→8
Absorption correction: multi-scan (SADABS; Bruker, 2005)	k = −9→9
T_min = 0.972, T_max = 0.983	l = −20→20
8993 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.061	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.211	H-atom parameters constrained
S = 1.08	w = 1/[σ²(F_o²) + (0.0973P)² + 0.0736P] where P = (F_o² + 2F_c²)/3
3688 reflections	(Δ/σ)_max < 0.001
185 parameters	Δρ_max = 0.19 e Å⁻³
0 restraints	Δρ_min = −0.18 e Å⁻³

Crystal data top

C₁₇H₁₉NO₂	γ = 73.527 (2)°
M_r = 269.33	V = 769.12 (7) Å³
Triclinic, P1	Z = 2
a = 7.0144 (4) Å	Mo Kα radiation
b = 7.4488 (4) Å	µ = 0.08 mm⁻¹
c = 15.6202 (8) Å	T = 296 K
α = 81.987 (2)°	0.34 × 0.25 × 0.22 mm
β = 81.009 (3)°

Data collection top

Bruker Kappa APEXII CCD diffractometer	3688 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	2028 reflections with I > 2σ(I)
T_min = 0.972, T_max = 0.983	R_int = 0.019
8993 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.061	0 restraints
wR(F²) = 0.211	H-atom parameters constrained
S = 1.08	Δρ_max = 0.19 e Å⁻³
3688 reflections	Δρ_min = −0.18 e Å⁻³
185 parameters

Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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 (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.4243 (2)	1.3278 (2)	0.06049 (11)	0.1032 (6)
O2	0.0678 (3)	1.5334 (3)	0.09093 (12)	0.1237 (7)
N1	0.4479 (2)	0.7156 (3)	0.26807 (10)	0.0781 (6)
C1	0.4907 (3)	0.5385 (3)	0.31797 (12)	0.0724 (7)
C2	0.6399 (3)	0.4985 (2)	0.37272 (11)	0.0653 (6)
C3	0.6892 (3)	0.3227 (3)	0.42177 (13)	0.0801 (7)
C4	0.5942 (5)	0.1908 (3)	0.41376 (19)	0.1067 (10)
C5	0.4515 (5)	0.2251 (4)	0.3599 (2)	0.1191 (11)
C6	0.3959 (4)	0.4001 (4)	0.31104 (18)	0.1058 (10)
C7	0.7449 (3)	0.6439 (3)	0.38007 (15)	0.0814 (7)
C8	0.8467 (4)	0.2768 (3)	0.48259 (17)	0.1107 (10)
C9	0.2673 (3)	0.8109 (4)	0.26475 (13)	0.0873 (8)
C10	0.2098 (3)	0.9939 (4)	0.21549 (13)	0.0872 (8)
C11	0.3509 (3)	1.0665 (3)	0.15843 (12)	0.0804 (7)
C12	0.2991 (3)	1.2443 (3)	0.11668 (13)	0.0845 (7)
C13	0.1014 (3)	1.3574 (4)	0.13272 (14)	0.0982 (9)
C14	−0.0383 (3)	1.2866 (5)	0.18777 (16)	0.1098 (12)
C15	0.0153 (3)	1.1059 (5)	0.22878 (16)	0.1091 (12)
C16	0.6230 (3)	1.2208 (3)	0.03706 (18)	0.1017 (9)
C17	−0.1297 (4)	1.6586 (5)	0.1040 (2)	0.1511 (14)
H4	0.62832	0.07416	0.44610	0.1282*
H5	0.38993	0.13205	0.35542	0.1429*
H6	0.29718	0.42404	0.27438	0.1267*
H7A	0.71156	0.74586	0.33535	0.1221*
H7B	0.88706	0.58857	0.37339	0.1221*
H7C	0.70333	0.69060	0.43618	0.1221*
H8A	0.84583	0.15970	0.51705	0.1659*
H8B	0.81876	0.37504	0.52020	0.1659*
H8C	0.97589	0.26637	0.44934	0.1659*
H9	0.16648	0.76071	0.29555	0.1047*
H11	0.48208	0.99265	0.14874	0.0964*
H14	−0.16955	1.36030	0.19753	0.1317*
H15	−0.08069	1.05903	0.26580	0.1308*
H16A	0.69124	1.18297	0.08799	0.1523*
H16B	0.69194	1.29576	−0.00456	0.1523*
H16C	0.62060	1.11121	0.01184	0.1523*
H17A	−0.22229	1.60982	0.08122	0.2265*
H17B	−0.12956	1.78039	0.07430	0.2265*
H17C	−0.16937	1.66912	0.16514	0.2265*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0793 (9)	0.1041 (11)	0.0950 (11)	0.0173 (8)	−0.0053 (8)	0.0011 (8)
O2	0.0955 (11)	0.1343 (14)	0.0975 (12)	0.0434 (10)	−0.0131 (9)	−0.0186 (10)
N1	0.0689 (10)	0.1016 (12)	0.0657 (10)	−0.0269 (9)	−0.0016 (7)	−0.0135 (8)
C1	0.0726 (11)	0.0870 (13)	0.0648 (10)	−0.0362 (10)	0.0107 (9)	−0.0220 (9)
C2	0.0683 (10)	0.0677 (11)	0.0609 (10)	−0.0251 (8)	0.0103 (8)	−0.0157 (8)
C3	0.0919 (13)	0.0699 (12)	0.0725 (12)	−0.0256 (10)	0.0236 (10)	−0.0164 (9)
C4	0.133 (2)	0.0838 (15)	0.1044 (19)	−0.0482 (15)	0.0309 (16)	−0.0238 (13)
C5	0.144 (2)	0.1027 (19)	0.133 (2)	−0.0808 (18)	0.034 (2)	−0.0442 (18)
C6	0.1058 (17)	0.139 (2)	0.0977 (17)	−0.0668 (16)	0.0115 (13)	−0.0523 (16)
C7	0.0819 (12)	0.0803 (12)	0.0893 (14)	−0.0328 (10)	−0.0139 (10)	−0.0060 (10)
C8	0.124 (2)	0.0967 (16)	0.0917 (17)	−0.0090 (15)	−0.0065 (15)	0.0061 (13)
C9	0.0686 (12)	0.1318 (18)	0.0640 (12)	−0.0304 (12)	−0.0026 (9)	−0.0174 (12)
C10	0.0633 (11)	0.1337 (19)	0.0587 (11)	−0.0106 (11)	−0.0090 (9)	−0.0217 (12)
C11	0.0590 (10)	0.1120 (16)	0.0585 (10)	0.0010 (10)	−0.0108 (8)	−0.0156 (10)
C12	0.0670 (11)	0.1122 (16)	0.0570 (11)	0.0084 (11)	−0.0100 (9)	−0.0159 (10)
C13	0.0765 (13)	0.130 (2)	0.0626 (12)	0.0260 (13)	−0.0180 (10)	−0.0259 (12)
C14	0.0621 (12)	0.167 (3)	0.0755 (14)	0.0215 (14)	−0.0105 (11)	−0.0365 (15)
C15	0.0625 (12)	0.178 (3)	0.0730 (14)	−0.0054 (15)	−0.0046 (10)	−0.0264 (16)
C16	0.0696 (12)	0.0984 (16)	0.122 (2)	−0.0017 (11)	−0.0060 (12)	−0.0103 (14)
C17	0.114 (2)	0.163 (3)	0.118 (2)	0.0679 (19)	−0.0177 (17)	−0.035 (2)

Geometric parameters (Å, º) top

O1—C12	1.358 (3)	C14—C15	1.383 (5)
O1—C16	1.416 (3)	C4—H4	0.9300
O2—C13	1.355 (3)	C5—H5	0.9300
O2—C17	1.436 (4)	C6—H6	0.9300
N1—C1	1.414 (3)	C7—H7A	0.9600
N1—C9	1.270 (3)	C7—H7B	0.9600
C1—C2	1.396 (3)	C7—H7C	0.9600
C1—C6	1.400 (4)	C8—H8A	0.9600
C2—C3	1.403 (3)	C8—H8B	0.9600
C2—C7	1.497 (3)	C8—H8C	0.9600
C3—C4	1.363 (4)	C9—H9	0.9300
C3—C8	1.504 (4)	C11—H11	0.9300
C4—C5	1.354 (5)	C14—H14	0.9300
C5—C6	1.400 (4)	C15—H15	0.9300
C9—C10	1.451 (4)	C16—H16A	0.9600
C10—C11	1.400 (3)	C16—H16B	0.9600
C10—C15	1.384 (4)	C16—H16C	0.9600
C11—C12	1.368 (3)	C17—H17A	0.9600
C12—C13	1.408 (3)	C17—H17B	0.9600
C13—C14	1.372 (3)	C17—H17C	0.9600

C12—O1—C16	118.63 (17)	C5—C6—H6	120.00
C13—O2—C17	118.4 (2)	C2—C7—H7A	109.00
C1—N1—C9	119.83 (19)	C2—C7—H7B	109.00
N1—C1—C2	118.28 (18)	C2—C7—H7C	109.00
N1—C1—C6	122.3 (2)	H7A—C7—H7B	109.00
C2—C1—C6	119.3 (2)	H7A—C7—H7C	109.00
C1—C2—C3	119.81 (18)	H7B—C7—H7C	109.00
C1—C2—C7	120.07 (16)	C3—C8—H8A	109.00
C3—C2—C7	120.11 (18)	C3—C8—H8B	109.00
C2—C3—C4	119.6 (2)	C3—C8—H8C	109.00
C2—C3—C8	121.02 (19)	H8A—C8—H8B	109.00
C4—C3—C8	119.4 (2)	H8A—C8—H8C	109.00
C3—C4—C5	121.7 (2)	H8B—C8—H8C	109.00
C4—C5—C6	120.3 (3)	N1—C9—H9	118.00
C1—C6—C5	119.3 (3)	C10—C9—H9	118.00
N1—C9—C10	123.5 (2)	C10—C11—H11	119.00
C9—C10—C11	121.3 (2)	C12—C11—H11	119.00
C9—C10—C15	120.1 (2)	C13—C14—H14	120.00
C11—C10—C15	118.5 (2)	C15—C14—H14	120.00
C10—C11—C12	121.1 (2)	C10—C15—H15	120.00
O1—C12—C11	125.7 (2)	C14—C15—H15	120.00
O1—C12—C13	114.90 (19)	O1—C16—H16A	109.00
C11—C12—C13	119.4 (2)	O1—C16—H16B	109.00
O2—C13—C12	114.7 (2)	O1—C16—H16C	109.00
O2—C13—C14	125.5 (3)	H16A—C16—H16B	109.00
C12—C13—C14	119.8 (3)	H16A—C16—H16C	109.00
C13—C14—C15	120.2 (3)	H16B—C16—H16C	109.00
C10—C15—C14	120.9 (2)	O2—C17—H17A	109.00
C3—C4—H4	119.00	O2—C17—H17B	109.00
C5—C4—H4	119.00	O2—C17—H17C	109.00
C4—C5—H5	120.00	H17A—C17—H17B	109.00
C6—C5—H5	120.00	H17A—C17—H17C	109.00
C1—C6—H6	120.00	H17B—C17—H17C	110.00

C16—O1—C12—C11	4.7 (3)	C8—C3—C4—C5	−180.0 (3)
C16—O1—C12—C13	−176.7 (2)	C3—C4—C5—C6	−0.6 (5)
C17—O2—C13—C12	−179.7 (2)	C4—C5—C6—C1	0.5 (4)
C17—O2—C13—C14	−0.3 (4)	N1—C9—C10—C11	8.8 (4)
C9—N1—C1—C2	−133.8 (2)	N1—C9—C10—C15	−166.8 (2)
C9—N1—C1—C6	49.3 (3)	C9—C10—C11—C12	−175.4 (2)
C1—N1—C9—C10	179.8 (2)	C15—C10—C11—C12	0.2 (3)
N1—C1—C2—C3	−178.66 (18)	C9—C10—C15—C14	174.7 (2)
N1—C1—C2—C7	2.3 (3)	C11—C10—C15—C14	−1.0 (4)
C6—C1—C2—C3	−1.7 (3)	C10—C11—C12—O1	179.8 (2)
C6—C1—C2—C7	179.2 (2)	C10—C11—C12—C13	1.2 (3)
N1—C1—C6—C5	177.5 (2)	O1—C12—C13—O2	−1.3 (3)
C2—C1—C6—C5	0.6 (4)	O1—C12—C13—C14	179.3 (2)
C1—C2—C3—C4	1.7 (3)	C11—C12—C13—O2	177.4 (2)
C1—C2—C3—C8	−178.9 (2)	C11—C12—C13—C14	−2.0 (3)
C7—C2—C3—C4	−179.3 (2)	O2—C13—C14—C15	−178.1 (2)
C7—C2—C3—C8	0.2 (3)	C12—C13—C14—C15	1.2 (4)
C2—C3—C4—C5	−0.5 (4)	C13—C14—C15—C10	0.3 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C16—H16B···O2ⁱ	0.96	2.51	3.454 (3)	167

Symmetry code: (i) −x+1, −y+3, −z.

Experimental details

Crystal data
Chemical formula	C₁₇H₁₉NO₂
M_r	269.33
Crystal system, space group	Triclinic, P1
Temperature (K)	296
a, b, c (Å)	7.0144 (4), 7.4488 (4), 15.6202 (8)
α, β, γ (°)	81.987 (2), 81.009 (3), 73.527 (2)
V (Å³)	769.12 (7)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.34 × 0.25 × 0.22

Data collection
Diffractometer	Bruker Kappa APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.972, 0.983
No. of measured, independent and observed [I > 2σ(I)] reflections	8993, 3688, 2028
R_int	0.019
(sin θ/λ)_max (Å⁻¹)	0.668

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.061, 0.211, 1.08
No. of reflections	3688
No. of parameters	185
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.19, −0.18

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C16—H16B···O2ⁱ	0.96	2.51	3.454 (3)	167

Symmetry code: (i) −x+1, −y+3, −z.

Acknowledgements

The authors acknowledge the provision of funds for the purchase of the diffractometer and encouragement by Dr Muhammad Akram Chaudhary, former Vice Chancellor, University of Sargodha. Pakistan.

References

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