(N1E,N2E)-N1,N2-Bis(4-hex­yloxy-3-methoxy­benzyl­idene)ethane-1,2-diamine

Paul, A.; Punnoose, S.S.; Mary, N.L.; Narasimhaswamy, T.; Ramkumar, V.

doi:10.1107/S1600536810017125

organic compounds

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ISSN: 2056-9890

Volume 66| Part 6| June 2010| Page o1377

https://doi.org/10.1107/S1600536810017125

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(N¹E,N²E)-N¹,N²-Bis(4-hexyloxy-3-methoxybenzylidene)ethane-1,2-diamine

Anju Paul,^a Sherin Susan Punnoose,^a N. L. Mary,^a ^* T. Narasimhaswamy ^b and V. Ramkumar ^c

^aDepartment of Chemistry, Stella Maris College, Chennai, TamilNadu, India, ^bPolymer Division, C.L.R.I. Adyar, Chennai, TamilNadu, India, and ^cDepartment of Chemistry, IIT Madras, Chennai, TamilNadu, India
^*Correspondence e-mail: maryterry13@yahoo.co.in

(Received 26 April 2010; accepted 10 May 2010; online 19 May 2010)

The title compound, C₃₀H₄₄N₂O₄, was obtained from the dimerization of 4-hexyloxyvanillin with ethylenediamine in 95% methanol solution. It adopts a trans configuration with respect to the C=N bond and possesses a crystallographically imposed centre of symmetry.

Related literature

For Schiff bases derived from vanillin, see: Guo et al. (2008 ); Li (2008 ). For its biological activity, see: Liang et al. (2009 ); Lim et al. (2008 ). For the potential uses of molecular materials with supramolecular architectures in emerging technologies and medicine, see: Porta et al. (2008 ). For details of the preparation of the title compound, see: Dholakiya & Patel (2002 ); Maurya et al. (2003 ); Doyle et al. (2007 ).

Experimental

Crystal data

C₃₀H₄₄N₂O₄
M_r = 496.67
Triclinic, $[P \overline 1]$
a = 5.3025 (6) Å
b = 10.3777 (14) Å
c = 13.0463 (17) Å
α = 84.667 (6)°
β = 84.659 (6)°
γ = 89.045 (6)°
V = 711.67 (16) Å³
Z = 1
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 298 K
0.45 × 0.22 × 0.10 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2004 ) T_min = 0.967, T_max = 0.992
9758 measured reflections
3249 independent reflections
1873 reflections with I > 2σ(I)
R_int = 0.023

Refinement

R[F² > 2σ(F²)] = 0.053
wR(F²) = 0.167
S = 1.03
3249 reflections
165 parameters
H-atom parameters constrained
Δρ_max = 0.22 e Å⁻³
Δρ_min = −0.23 e Å⁻³

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810017125/jh2151sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810017125/jh2151Isup2.hkl

checkCIF report

Comment top

The title compound C₃₀H₄₄N₂O₄ is a synthetic analogue with a long aliphatic side chain of vanillin. The Schiff base derived from vanillin (Guo et.al, 2008; Li et.al, 2008) exhibit potential antibacterial activity and a potent anti-proliferative effect on a broad spectrum of cancer cell lines (Liang. et.al, 2009; Lim et.al, 2008).

The design of synthetic molecules with self-organised behaviour is one of the fastest growing areas of research. Molecular materials that arise from the self organising properties of the molecules may afford supramolecular architectures (structures beyond the molecule) with chemical and physical properties that may become useful in emerging technologies and medicine (Porta et.al, 2008). Molecules that use non-covalent interactions to self-organise into supramolecular structures have the potential to generate functional materials with a broad range of applications. This unique combination of coordination bond and alkyl interdigitation provide exceptional control over intermolecular interactions and can generate nano scale molecular order as liquid crystalline states and Langmiur-Blodgett films on surfaces.

The crystal adopts a trans configuration with respect to the C=N bond and possesses a crystallographically imposed centre of symmetry.

Related literature top

For related literature, see: Guo et al., (2008); Liang et al., (2009); Lim et al., (2008); Porta et.al.,(2008);

Experimental top

1) Synthesis of 4-hexyloxy vanillin.

15.215g (0.1 mole) of vanillin was dissolved in 300ml of dimethylformamide in a round-bottom flask. 17.96g (0.13 mole) of potassium carbonate was also added. The resulting mixture was stirred by using a homogeniser maintaining the temperature at 90° C by using an oil bath. 14.03ml (0.1 mole) of bromohexane was added to the reaction mixture through a dropping funnel over a period of 30 minutes (Dholakiya et.al, 2002; Maurya et.al, 2003). The resulting mixture was stirred for 3 hours and cooled to room temperature, diluted with 600ml water. The contents were transferred to a separating funnel extracted with diethyl ether, washed with 5% KOH solution and water respectively. 4-hexyloxy vanillin was obtained and it was recrystallised from hot alcoholic solution.

2) Dimerisation of 4-hexyloxy vanillin with ethylenediamine.

3g (0.05 mole) of ethylenediamine was dissolved in 10ml of ethanol in a round-bottom flask. 23.6g (0.1 mole) of 4-hexyloxy vanillin and 5 drops of acetic acid were added into it. It was fitted to a water condenser and heated for 2 hours (Doyle et.al, 2007). It was allowed to cool, washed with methanol and dried in an oven. Recrystallisation of the compound from methanol gave X-ray diffraction quality crystals of the title compound.

Structure description top

The crystal adopts a trans configuration with respect to the C=N bond and possesses a crystallographically imposed centre of symmetry.

For related literature, see: Guo et al., (2008); Liang et al., (2009); Lim et al., (2008); Porta et.al.,(2008);

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. ORTEP of the molecule with atoms represented as 30% probability ellipsoids.

(N¹E,N²E)-N¹,N²-Bis(4- hexyloxy-3-methoxybenzylidene)ethane-1,2-diamine top

Crystal data top

C₃₀H₄₄N₂O₄	Z = 1
M_r = 496.67	F(000) = 270
Triclinic, P1	D_x = 1.159 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 5.3025 (6) Å	Cell parameters from 2606 reflections
b = 10.3777 (14) Å	θ = 2.5–24.8°
c = 13.0463 (17) Å	µ = 0.08 mm⁻¹
α = 84.667 (6)°	T = 298 K
β = 84.659 (6)°	Rectangular, colourless
γ = 89.045 (6)°	0.45 × 0.22 × 0.10 mm
V = 711.67 (16) Å³

Data collection top

Bruker APEXII CCD area-detector diffractometer	3249 independent reflections
Radiation source: fine-focus sealed tube	1873 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.023
phi and ω scans	θ_max = 28.3°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 2004)	h = −7→5
T_min = 0.967, T_max = 0.992	k = −13→13
9758 measured reflections	l = −17→17

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)] = 0.053	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.167	H-atom parameters constrained
S = 1.03	w = 1/[σ²(F_o²) + (0.0813P)² + 0.0648P] where P = (F_o² + 2F_c²)/3
3249 reflections	(Δ/σ)_max < 0.001
165 parameters	Δρ_max = 0.22 e Å⁻³
0 restraints	Δρ_min = −0.23 e Å⁻³

Crystal data top

C₃₀H₄₄N₂O₄	γ = 89.045 (6)°
M_r = 496.67	V = 711.67 (16) Å³
Triclinic, P1	Z = 1
a = 5.3025 (6) Å	Mo Kα radiation
b = 10.3777 (14) Å	µ = 0.08 mm⁻¹
c = 13.0463 (17) Å	T = 298 K
α = 84.667 (6)°	0.45 × 0.22 × 0.10 mm
β = 84.659 (6)°

Data collection top

Bruker APEXII CCD area-detector diffractometer	3249 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2004)	1873 reflections with I > 2σ(I)
T_min = 0.967, T_max = 0.992	R_int = 0.023
9758 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.053	0 restraints
wR(F²) = 0.167	H-atom parameters constrained
S = 1.03	Δρ_max = 0.22 e Å⁻³
3249 reflections	Δρ_min = −0.23 e Å⁻³
165 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.

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 > 2sigma(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
C1	1.3152 (4)	0.4143 (2)	0.8601 (2)	0.0941 (7)
H1A	1.4109	0.4622	0.9025	0.141*
H1B	1.4280	0.3615	0.8196	0.141*
H1C	1.1958	0.3602	0.9034	0.141*
C2	1.1755 (4)	0.50694 (19)	0.78939 (16)	0.0719 (6)
H2A	1.2985	0.5568	0.7428	0.086*
H2B	1.0780	0.4574	0.7477	0.086*
C3	0.9998 (3)	0.59913 (17)	0.84379 (14)	0.0583 (5)
H3A	1.0965	0.6484	0.8860	0.070*
H3B	0.8748	0.5497	0.8896	0.070*
C4	0.8650 (3)	0.69171 (18)	0.77122 (14)	0.0581 (5)
H4A	0.7761	0.6418	0.7268	0.070*
H4B	0.9911	0.7430	0.7274	0.070*
C5	0.6765 (3)	0.78325 (16)	0.82227 (13)	0.0521 (4)
H5A	0.5492	0.7336	0.8667	0.063*
H5B	0.7635	0.8366	0.8648	0.063*
C6	0.5513 (3)	0.86768 (16)	0.74259 (13)	0.0515 (4)
H6A	0.6769	0.9218	0.7011	0.062*
H6B	0.4736	0.8144	0.6971	0.062*
C7	0.2265 (3)	1.02721 (15)	0.72825 (12)	0.0446 (4)
C8	0.2641 (3)	1.03991 (17)	0.62159 (12)	0.0555 (5)
H8	0.3923	0.9928	0.5882	0.067*
C9	0.1123 (3)	1.12212 (18)	0.56439 (13)	0.0591 (5)
H9	0.1388	1.1290	0.4926	0.071*
C10	−0.0761 (3)	1.19360 (15)	0.61098 (12)	0.0487 (4)
C11	−0.1152 (3)	1.18130 (15)	0.71918 (12)	0.0494 (4)
H11	−0.2432	1.2293	0.7520	0.059*
C12	0.0324 (3)	1.09964 (14)	0.77722 (11)	0.0447 (4)
C13	−0.2366 (4)	1.27834 (18)	0.54763 (14)	0.0602 (5)
H13	−0.2200	1.2727	0.4766	0.072*
C14	−0.5432 (4)	1.43145 (18)	0.50776 (15)	0.0694 (6)
H14A	−0.7211	1.4286	0.5331	0.083*
H14B	−0.5236	1.3933	0.4424	0.083*
C15	−0.2111 (4)	1.13500 (19)	0.93525 (13)	0.0670 (5)
H15A	−0.1983	1.2276	0.9260	0.101*
H15B	−0.2181	1.1066	1.0076	0.101*
H15C	−0.3621	1.1088	0.9078	0.101*
N1	−0.3933 (3)	1.35719 (15)	0.58257 (12)	0.0671 (5)
O1	0.3626 (2)	0.94721 (10)	0.79130 (8)	0.0519 (3)
O2	0.0049 (2)	1.07846 (12)	0.88225 (8)	0.0605 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0811 (16)	0.0828 (16)	0.1147 (19)	0.0396 (13)	−0.0043 (14)	−0.0015 (14)
C2	0.0653 (12)	0.0674 (12)	0.0814 (13)	0.0241 (10)	0.0002 (10)	−0.0095 (10)
C3	0.0479 (10)	0.0593 (11)	0.0672 (11)	0.0142 (8)	−0.0050 (8)	−0.0067 (9)
C4	0.0467 (10)	0.0634 (11)	0.0629 (11)	0.0134 (9)	−0.0027 (8)	−0.0038 (9)
C5	0.0451 (9)	0.0534 (10)	0.0577 (10)	0.0132 (8)	−0.0068 (7)	−0.0043 (8)
C6	0.0430 (9)	0.0546 (10)	0.0564 (10)	0.0115 (8)	−0.0023 (7)	−0.0076 (8)
C7	0.0454 (9)	0.0438 (9)	0.0441 (9)	0.0079 (7)	−0.0086 (7)	0.0017 (7)
C8	0.0561 (10)	0.0636 (11)	0.0444 (9)	0.0144 (9)	0.0013 (8)	−0.0004 (8)
C9	0.0700 (12)	0.0654 (11)	0.0395 (9)	0.0083 (10)	−0.0055 (8)	0.0058 (8)
C10	0.0595 (11)	0.0427 (9)	0.0442 (9)	0.0042 (8)	−0.0163 (7)	0.0047 (7)
C11	0.0590 (10)	0.0427 (9)	0.0472 (9)	0.0153 (8)	−0.0132 (8)	−0.0016 (7)
C12	0.0539 (10)	0.0414 (8)	0.0388 (8)	0.0091 (8)	−0.0094 (7)	−0.0007 (6)
C13	0.0760 (13)	0.0563 (11)	0.0489 (10)	0.0035 (10)	−0.0167 (9)	0.0026 (8)
C14	0.0782 (14)	0.0599 (11)	0.0704 (12)	0.0094 (10)	−0.0297 (10)	0.0136 (9)
C15	0.0789 (13)	0.0752 (13)	0.0447 (9)	0.0331 (10)	−0.0010 (9)	−0.0037 (8)
N1	0.0792 (11)	0.0629 (10)	0.0585 (9)	0.0163 (9)	−0.0208 (8)	0.0088 (8)
O1	0.0519 (7)	0.0569 (7)	0.0461 (6)	0.0233 (6)	−0.0072 (5)	−0.0009 (5)
O2	0.0727 (8)	0.0701 (8)	0.0373 (6)	0.0373 (6)	−0.0073 (5)	−0.0017 (5)

Geometric parameters (Å, º) top

C1—C2	1.504 (3)	C7—C12	1.405 (2)
C1—H1A	0.9600	C8—C9	1.380 (2)
C1—H1B	0.9600	C8—H8	0.9300
C1—H1C	0.9600	C9—C10	1.365 (2)
C2—C3	1.503 (2)	C9—H9	0.9300
C2—H2A	0.9700	C10—C11	1.402 (2)
C2—H2B	0.9700	C10—C13	1.467 (2)
C3—C4	1.505 (3)	C11—C12	1.369 (2)
C3—H3A	0.9700	C11—H11	0.9300
C3—H3B	0.9700	C12—O2	1.3620 (18)
C4—C5	1.519 (2)	C13—N1	1.243 (2)
C4—H4A	0.9700	C13—H13	0.9300
C4—H4B	0.9700	C14—N1	1.470 (2)
C5—C6	1.493 (2)	C14—C14ⁱ	1.492 (4)
C5—H5A	0.9700	C14—H14A	0.9700
C5—H5B	0.9700	C14—H14B	0.9700
C6—O1	1.4274 (18)	C15—O2	1.428 (2)
C6—H6A	0.9700	C15—H15A	0.9600
C6—H6B	0.9700	C15—H15B	0.9600
C7—O1	1.3602 (18)	C15—H15C	0.9600
C7—C8	1.382 (2)

C2—C1—H1A	109.5	O1—C7—C8	124.79 (15)
C2—C1—H1B	109.5	O1—C7—C12	116.27 (13)
H1A—C1—H1B	109.5	C8—C7—C12	118.93 (14)
C2—C1—H1C	109.5	C9—C8—C7	120.33 (16)
H1A—C1—H1C	109.5	C9—C8—H8	119.8
H1B—C1—H1C	109.5	C7—C8—H8	119.8
C3—C2—C1	114.57 (19)	C10—C9—C8	121.35 (15)
C3—C2—H2A	108.6	C10—C9—H9	119.3
C1—C2—H2A	108.6	C8—C9—H9	119.3
C3—C2—H2B	108.6	C9—C10—C11	118.64 (15)
C1—C2—H2B	108.6	C9—C10—C13	119.84 (15)
H2A—C2—H2B	107.6	C11—C10—C13	121.51 (16)
C2—C3—C4	113.47 (16)	C12—C11—C10	120.86 (15)
C2—C3—H3A	108.9	C12—C11—H11	119.6
C4—C3—H3A	108.9	C10—C11—H11	119.6
C2—C3—H3B	108.9	O2—C12—C11	125.23 (14)
C4—C3—H3B	108.9	O2—C12—C7	114.87 (13)
H3A—C3—H3B	107.7	C11—C12—C7	119.88 (14)
C3—C4—C5	115.64 (15)	N1—C13—C10	124.35 (17)
C3—C4—H4A	108.4	N1—C13—H13	117.8
C5—C4—H4A	108.4	C10—C13—H13	117.8
C3—C4—H4B	108.4	N1—C14—C14ⁱ	109.91 (19)
C5—C4—H4B	108.4	N1—C14—H14A	109.7
H4A—C4—H4B	107.4	C14ⁱ—C14—H14A	109.7
C6—C5—C4	110.57 (14)	N1—C14—H14B	109.7
C6—C5—H5A	109.5	C14ⁱ—C14—H14B	109.7
C4—C5—H5A	109.5	H14A—C14—H14B	108.2
C6—C5—H5B	109.5	O2—C15—H15A	109.5
C4—C5—H5B	109.5	O2—C15—H15B	109.5
H5A—C5—H5B	108.1	H15A—C15—H15B	109.5
O1—C6—C5	110.11 (13)	O2—C15—H15C	109.5
O1—C6—H6A	109.6	H15A—C15—H15C	109.5
C5—C6—H6A	109.6	H15B—C15—H15C	109.5
O1—C6—H6B	109.6	C13—N1—C14	116.83 (17)
C5—C6—H6B	109.6	C7—O1—C6	116.96 (12)
H6A—C6—H6B	108.2	C12—O2—C15	117.33 (12)

C1—C2—C3—C4	179.30 (18)	O1—C7—C12—O2	−0.7 (2)
C2—C3—C4—C5	177.47 (15)	C8—C7—C12—O2	178.37 (15)
C3—C4—C5—C6	−178.66 (15)	O1—C7—C12—C11	−179.24 (14)
C4—C5—C6—O1	176.14 (13)	C8—C7—C12—C11	−0.2 (2)
O1—C7—C8—C9	178.75 (15)	C9—C10—C13—N1	−171.75 (17)
C12—C7—C8—C9	−0.2 (3)	C11—C10—C13—N1	9.9 (3)
C7—C8—C9—C10	0.6 (3)	C10—C13—N1—C14	−178.23 (15)
C8—C9—C10—C11	−0.6 (3)	C14ⁱ—C14—N1—C13	−107.7 (3)
C8—C9—C10—C13	−178.96 (16)	C8—C7—O1—C6	−2.4 (2)
C9—C10—C11—C12	0.1 (2)	C12—C7—O1—C6	176.64 (13)
C13—C10—C11—C12	178.52 (15)	C5—C6—O1—C7	−178.19 (13)
C10—C11—C12—O2	−178.15 (15)	C11—C12—O2—C15	7.1 (2)
C10—C11—C12—C7	0.2 (2)	C7—C12—O2—C15	−171.33 (15)

Symmetry code: (i) −x−1, −y+3, −z+1.

Experimental details

Crystal data
Chemical formula	C₃₀H₄₄N₂O₄
M_r	496.67
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	5.3025 (6), 10.3777 (14), 13.0463 (17)
α, β, γ (°)	84.667 (6), 84.659 (6), 89.045 (6)
V (Å³)	711.67 (16)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.45 × 0.22 × 0.10

Data collection
Diffractometer	Bruker APEXII CCD area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 2004)
T_min, T_max	0.967, 0.992
No. of measured, independent and observed [I > 2σ(I)] reflections	9758, 3249, 1873
R_int	0.023
(sin θ/λ)_max (Å⁻¹)	0.667

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.053, 0.167, 1.03
No. of reflections	3249
No. of parameters	165
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.23

Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT (Bruker, 2004), SAINT and XPREP (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).

Acknowledgements

The authors thank the UGC for a project grant. Special thanks go to the Principal, Dr Sr Jasintha Quadras, fmm, and the Head, Department of Chemistry, Stella Maris College, Chennai. The authors acknowledge the Department of Chemistry, IIT Madras, for the X-ray data collection.

References

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