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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 10| October 2012| Page o2990
https://doi.org/10.1107/S1600536812038354

2,2′-Di­eth­oxy-4,4′-[(E,E)-hydrazine­diyl­idenebis(methanylyl­idene)]diphenol

Wisam Naji Atiyah Al-Mehana,a Rosiyah Yahya,a Faridah Sonsudin,b Ihsan Naji Atiyah Al-Mehanac and Kong Mun Loa*

aDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, bCentre for Foundation Studies, University of Malaya, 50603 Kuala Lumpur, Malaysia, and cNursing Department, Kufa Technical Institute, PO Box 49, Kufa/Najaf, Iraq
*Correspondence e-mail: kmlo@um.edu.my

(Received 1 August 2012; accepted 7 September 2012; online 22 September 2012)

The complete molecule of the title compound, C18H20N2O4, is generated by inversion symmetry. The conformation around the C=N bond is E. With the exception of the eth­oxy substituent, the mol­ecule is essentially planar with an r.m.s. deviation of 0.0455 Å. In the crystal, mol­ecules are linked by O—H⋯N hydrogen bonds into a two-dimensional supra­molecular network parallel to the bc plane.

Related literature

For the structure of 4,4′-(1E,1′E)-1,2-diylidenebis(methan-1-yl-1-yl­idene) bis­(2-meth­oxy­phenol), see: Qu et al. (2005[Qu, Y. & Sun, X.-M. (2005). Acta Cryst. E61, o3828-o3830.]). For applications of azines and their derivatives, see: Dudis et al. (1993[Dudis, D. S., Yeates, A. T. & Kost, D. (1993). J. Am. Chem. Soc. 115, 8770-8774.]); Facchetti et al. (2002[Facchetti, A., Abbotto, A., Beverina, L., van der Boom, M. E., Dutta, P., Evmenenko, G., Marks, T. J. & Pagani, G. A. (2002). Chem. Mater. 14, 4996-5005.]); Kim et al. (2010[Kim, S. H., Gwon, S. Y., Burkinshaw, S. M. & Son, Y. A. (2010). Dyes Pigm. 87, 268-271.]); Pandeya et al. (1999[Pandeya, S. N., Sriram, D., Nath, G. & Clercq, E. De. (1999). Pharmaceutica Acta Helvetiae, 74, 11-17.]); Wadher et al. (2009[Wadher, J. S., Puranik, M. P., Karande, N. A. & Yeole, P. G. (2009). J. PharmaTech Research 1, 22-33.]).

[Scheme 1]

Experimental

Crystal data

  • C18H20N2O4

  • Mr = 328.36

  • Monoclinic, P 21 /n

  • a = 5.2176 (1) Å

  • b = 10.3422 (1) Å

  • c = 14.9135 (2) Å

  • β = 97.206 (1)°

  • V = 798.40 (2) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 100 K

  • 0.16 × 0.08 × 0.08 mm
Data collection

  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996)[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.] Tmin = 0.650, Tmax = 0.746

  • 7447 measured reflections

  • 1831 independent reflections

  • 1654 reflections with I > 2σ(I)

  • Rint = 0.020
Refinement

  • R[F2 > 2σ(F2)] = 0.034

  • wR(F2) = 0.098

  • S = 1.05

  • 1831 reflections

  • 111 parameters

  • H-atom parameters constrained

  • Δρmax = 0.33 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O2—H2⋯N1i 0.84 1.99 2.7787 (12) 156
Symmetry code: (i) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: X-SEED (Barbour, 2001[Barbour, L. J. (2001). J. Supramol. Chem. 1, 189-191.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536812038354/zj2092sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812038354/zj2092Isup2.hkl

checkCIF report


Comment top

Aromatic carbonyl compounds react easily with hydrazine forming hydrazones, which could condense with a second molecule of the carbonyl compound to yield an azine. Due to the fascinating physical and chemical properties, azines and their derivatives have been extensively applied in such area as dyes [Kim et al.], non-linear fluorophores [Facchetti et al.], biological and pharmaceutical applications [Wadher et al., Pandeya et al.]. Furthermore, there are many reports on polyazines as highly conjugated polymers in electronic, optoelectronic and photonic applications [Dudis et al]. In our work on a new class of monomers based upon the hydrazone moieties, we report here a new bis imine monomer. The title compound, C18H20N2O4, is centrosymmetric around the central azine bond [N1—N1i = 1.416 (2) Å; symmetry operation i: -x + 2, -y + 1, -z + 1], with the E configuration around the N1=C1 bond [1.284 (1) Å]. In the crystal structure of the title compound in Fig 2, the molecules are linked together by O–H···N hydrogen bonds [O2—H2···N1ii = 2.7782 (12) Å; symmetry operation ii: 3/2 - x, 1/2 + y, 1/2 + z] resulting in the formation of a two-dimensional supramolecular network which propagated parallel to the bc plane. C—H···pi interaction is also present; C8—H8b···Cg1iii = 2.71 Å where Cg1 is the centroid of the ring C2 - C7, [symmetry code: (iii) -1 + x, y, z].In contrast to the title compound, the methoxy substituted analogue [Qu, et al.] consists of two asymmetric units with the presence of additional intermolecular O—H..O hydrogen bonds with the adjacent asymmetric unit.

Related literature top

For the structure of 4,4'-(1E,1'E)-1,2-diylidenebis(methan-1-yl-1-ylidene) bis(2-methoxyphenol), see: Qu et al. (2005). For applications of azines and their derivatives, see: Dudis et al. (1993); Facchetti et al. (2002); Kim et al. (2010); Pandeya et al. (1999); Wadher et al. (2009).

Experimental top

A mixture of 3-ethoxy-4-hydroxybenzaldehyde (3 g, 18 mmol), hydrazine sulfate (1.17 g, 9 mmol) and 1.7 ml of concentrated ammonia solution in 20 ml of 95% ethanol was stirred for 3 h. The solvent was removed under reduced pressure and the yellow residue was recrystallized from tetrahydrofuran to yield yellow crystals, m.p. 471 - 472 K.

Refinement top

Hydrogen atoms were placed at calculated positions (C–H 0.95 to 0.99 Å and O–H 0.84 Å) and were treated as riding on their parent carbon atoms, with U(H) set to 1.2–1.5 times Ueq(C).

Structure description top

Aromatic carbonyl compounds react easily with hydrazine forming hydrazones, which could condense with a second molecule of the carbonyl compound to yield an azine. Due to the fascinating physical and chemical properties, azines and their derivatives have been extensively applied in such area as dyes [Kim et al.], non-linear fluorophores [Facchetti et al.], biological and pharmaceutical applications [Wadher et al., Pandeya et al.]. Furthermore, there are many reports on polyazines as highly conjugated polymers in electronic, optoelectronic and photonic applications [Dudis et al]. In our work on a new class of monomers based upon the hydrazone moieties, we report here a new bis imine monomer. The title compound, C18H20N2O4, is centrosymmetric around the central azine bond [N1—N1i = 1.416 (2) Å; symmetry operation i: -x + 2, -y + 1, -z + 1], with the E configuration around the N1=C1 bond [1.284 (1) Å]. In the crystal structure of the title compound in Fig 2, the molecules are linked together by O–H···N hydrogen bonds [O2—H2···N1ii = 2.7782 (12) Å; symmetry operation ii: 3/2 - x, 1/2 + y, 1/2 + z] resulting in the formation of a two-dimensional supramolecular network which propagated parallel to the bc plane. C—H···pi interaction is also present; C8—H8b···Cg1iii = 2.71 Å where Cg1 is the centroid of the ring C2 - C7, [symmetry code: (iii) -1 + x, y, z].In contrast to the title compound, the methoxy substituted analogue [Qu, et al.] consists of two asymmetric units with the presence of additional intermolecular O—H..O hydrogen bonds with the adjacent asymmetric unit.

For the structure of 4,4'-(1E,1'E)-1,2-diylidenebis(methan-1-yl-1-ylidene) bis(2-methoxyphenol), see: Qu et al. (2005). For applications of azines and their derivatives, see: Dudis et al. (1993); Facchetti et al. (2002); Kim et al. (2010); Pandeya et al. (1999); Wadher et al. (2009).

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: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of 4,4'-(1E,1'E)-1,2-diylidenebis(methan-1-yl-1-ylidene) bis(2-ethoxyphenol) showing 50% probability displacement ellipsoids. Hydrogen atoms are drawn as spheres of arbitrary radius. Symmetry operation i: -x + 2, -y + 1, -z + 1.
[Figure 2] Fig. 2. A view of the two-dimensional supramolecular network in the title compound showing the O—H···N hydrogen bonds (in red dotted lines).
2,2'-Diethoxy-4,4'-[(E,E)- hydrazinediylidenebis(methanylylidene)]diphenol top
Crystal data top
C18H20N2O4F(000) = 348
Mr = 328.36Dx = 1.366 Mg m−3
Monoclinic, P21/nMelting point = 471–472 K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 5.2176 (1) ÅCell parameters from 4187 reflections
b = 10.3422 (1) Åθ = 2.4–28.4°
c = 14.9135 (2) ŵ = 0.10 mm−1
β = 97.206 (1)°T = 100 K
V = 798.40 (2) Å3Block, yellow
Z = 20.16 × 0.08 × 0.08 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer		1831 independent reflections
Radiation source: fine-focus sealed tube1654 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.020
ω scansθmax = 27.5°, θmin = 2.4°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −6→6
Tmin = 0.650, Tmax = 0.746k = −13→13
7447 measured reflectionsl = −19→18
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.034Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.098H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.052P)2 + 0.3158P]
where P = (Fo2 + 2Fc2)/3
1831 reflections(Δ/σ)max < 0.001
111 parametersΔρmax = 0.33 e Å−3
0 restraintsΔρmin = −0.23 e Å−3
Crystal data top
C18H20N2O4V = 798.40 (2) Å3
Mr = 328.36Z = 2
Monoclinic, P21/nMo Kα radiation
a = 5.2176 (1) ŵ = 0.10 mm−1
b = 10.3422 (1) ÅT = 100 K
c = 14.9135 (2) Å0.16 × 0.08 × 0.08 mm
β = 97.206 (1)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer		1831 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		1654 reflections with I > 2σ(I)
Tmin = 0.650, Tmax = 0.746Rint = 0.020
7447 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0340 restraints
wR(F2) = 0.098H-atom parameters constrained
S = 1.05Δρmax = 0.33 e Å−3
1831 reflectionsΔρmin = −0.23 e Å−3
111 parameters
Special details top

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 (Å2) top
xyzUiso*/Ueq
C11.1226 (2)0.61425 (10)0.43730 (7)0.0140 (2)
H11.27700.62540.47760.017*
C21.0867 (2)0.69416 (10)0.35602 (7)0.0138 (2)
C31.2699 (2)0.79013 (10)0.34702 (7)0.0150 (2)
H31.41630.79820.39140.018*
C41.2397 (2)0.87397 (10)0.27353 (7)0.0149 (2)
H41.36470.93940.26830.018*
C51.0277 (2)0.86239 (10)0.20780 (7)0.0137 (2)
C60.84916 (19)0.76106 (10)0.21383 (7)0.0133 (2)
C70.87615 (19)0.67949 (10)0.28809 (7)0.0140 (2)
H70.75210.61350.29310.017*
C80.4920 (2)0.64171 (10)0.14038 (7)0.0163 (2)
H8B0.39660.64160.19370.020*
H8A0.59540.56140.14120.020*
C90.3053 (2)0.64918 (12)0.05452 (8)0.0217 (3)
H9A0.21110.73130.05290.033*
H9B0.18250.57720.05280.033*
H9C0.40110.64390.00220.033*
N10.95919 (17)0.52993 (9)0.45792 (6)0.0138 (2)
O10.65817 (14)0.75311 (7)0.14250 (5)0.0160 (2)
O21.00276 (14)0.94690 (7)0.13780 (5)0.01629 (19)
H20.84620.95320.11670.024*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0148 (5)0.0157 (5)0.0109 (5)0.0022 (4)−0.0010 (3)−0.0018 (4)
C20.0150 (5)0.0141 (5)0.0119 (5)0.0026 (4)0.0011 (4)−0.0007 (4)
C30.0139 (5)0.0169 (5)0.0136 (5)0.0009 (4)−0.0013 (4)−0.0016 (4)
C40.0143 (5)0.0141 (5)0.0162 (5)−0.0011 (4)0.0012 (4)−0.0007 (4)
C50.0155 (5)0.0131 (5)0.0127 (5)0.0020 (4)0.0025 (4)0.0007 (4)
C60.0125 (5)0.0146 (5)0.0123 (5)0.0010 (4)−0.0004 (4)−0.0009 (4)
C70.0147 (5)0.0139 (5)0.0134 (5)−0.0002 (4)0.0012 (4)0.0004 (4)
C80.0168 (5)0.0154 (5)0.0156 (5)−0.0036 (4)−0.0017 (4)0.0009 (4)
C90.0225 (6)0.0236 (6)0.0172 (5)−0.0062 (4)−0.0043 (4)0.0018 (4)
N10.0162 (4)0.0148 (4)0.0098 (4)0.0031 (3)−0.0008 (3)0.0004 (3)
O10.0162 (4)0.0167 (4)0.0135 (4)−0.0036 (3)−0.0039 (3)0.0033 (3)
O20.0144 (4)0.0169 (4)0.0167 (4)−0.0009 (3)−0.0014 (3)0.0052 (3)
Geometric parameters (Å, º) top
C1—N11.2835 (14)C6—C71.3853 (14)
C1—C21.4596 (14)C7—H70.9500
C1—H10.9500C8—O11.4399 (12)
C2—C31.3959 (15)C8—C91.5106 (14)
C2—C71.4062 (14)C8—H8B0.9900
C3—C41.3910 (15)C8—H8A0.9900
C3—H30.9500C9—H9A0.9800
C4—C51.3880 (14)C9—H9B0.9800
C4—H40.9500C9—H9C0.9800
C5—O21.3551 (12)N1—N1i1.4163 (16)
C5—C61.4126 (14)O2—H20.8400
C6—O11.3658 (12)
N1—C1—C2124.33 (9)C6—C7—C2120.14 (9)
N1—C1—H1117.8C6—C7—H7119.9
C2—C1—H1117.8C2—C7—H7119.9
C3—C2—C7119.34 (9)O1—C8—C9107.47 (8)
C3—C2—C1117.68 (9)O1—C8—H8B110.2
C7—C2—C1122.98 (9)C9—C8—H8B110.2
C4—C3—C2120.52 (9)O1—C8—H8A110.2
C4—C3—H3119.7C9—C8—H8A110.2
C2—C3—H3119.7H8B—C8—H8A108.5
C5—C4—C3120.27 (10)C8—C9—H9A109.5
C5—C4—H4119.9C8—C9—H9B109.5
C3—C4—H4119.9H9A—C9—H9B109.5
O2—C5—C4118.65 (9)C8—C9—H9C109.5
O2—C5—C6121.81 (9)H9A—C9—H9C109.5
C4—C5—C6119.51 (9)H9B—C9—H9C109.5
O1—C6—C7125.25 (9)C1—N1—N1i111.99 (10)
O1—C6—C5114.69 (9)C6—O1—C8116.35 (8)
C7—C6—C5120.07 (9)C5—O2—H2109.5
N1—C1—C2—C3174.08 (10)C4—C5—C6—C74.43 (15)
N1—C1—C2—C7−5.05 (16)O1—C6—C7—C2177.64 (9)
C7—C2—C3—C42.56 (15)C5—C6—C7—C2−2.41 (15)
C1—C2—C3—C4−176.60 (9)C3—C2—C7—C6−1.07 (15)
C2—C3—C4—C5−0.53 (16)C1—C2—C7—C6178.05 (9)
C3—C4—C5—O2179.09 (9)C2—C1—N1—N1i−178.00 (10)
C3—C4—C5—C6−2.96 (15)C7—C6—O1—C8−7.68 (15)
O2—C5—C6—O12.27 (14)C5—C6—O1—C8172.36 (9)
C4—C5—C6—O1−175.61 (9)C9—C8—O1—C6−177.35 (9)
O2—C5—C6—C7−177.68 (9)
Symmetry code: (i) −x+2, −y+1, −z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···N1ii0.841.992.7787 (12)156
Symmetry code: (ii) −x+3/2, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formulaC18H20N2O4
Mr328.36
Crystal system, space groupMonoclinic, P21/n
Temperature (K)100
a, b, c (Å)5.2176 (1), 10.3422 (1), 14.9135 (2)
β (°) 97.206 (1)
V (Å3)798.40 (2)
Z2
Radiation typeMo Kα
µ (mm−1)0.10
Crystal size (mm)0.16 × 0.08 × 0.08
Data collection
DiffractometerBruker APEXII CCD area-detector
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.650, 0.746
No. of measured, independent and
observed [I > 2σ(I)] reflections		7447, 1831, 1654
Rint0.020
(sin θ/λ)max (Å−1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.034, 0.098, 1.05
No. of reflections1831
No. of parameters111
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.33, −0.23

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···N1i0.841.992.7787 (12)155.9
Symmetry code: (i) −x+3/2, y+1/2, −z+1/2.
 

Acknowledgements

We thank the University of Malaya (UMRG grant No. RG183/11AFR and RG020/09AFR) for supporting this study.

References

First citationBarbour, L. J. (2001). J. Supramol. Chem. 1, 189–191.  CrossRef CAS Google Scholar
 First citationBruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationDudis, D. S., Yeates, A. T. & Kost, D. (1993). J. Am. Chem. Soc. 115, 8770–8774.  CrossRef CAS Web of Science Google Scholar
 First citationFacchetti, A., Abbotto, A., Beverina, L., van der Boom, M. E., Dutta, P., Evmenenko, G., Marks, T. J. & Pagani, G. A. (2002). Chem. Mater. 14, 4996–5005.  Web of Science CrossRef CAS Google Scholar
 First citationKim, S. H., Gwon, S. Y., Burkinshaw, S. M. & Son, Y. A. (2010). Dyes Pigm. 87, 268–271.  Web of Science CrossRef CAS Google Scholar
 First citationPandeya, S. N., Sriram, D., Nath, G. & Clercq, E. De. (1999). Pharmaceutica Acta Helvetiae, 74, 11–17.  CrossRef PubMed CAS Google Scholar
 First citationQu, Y. & Sun, X.-M. (2005). Acta Cryst. E61, o3828–o3830.  Web of Science CSD CrossRef IUCr Journals Google Scholar
 First citationSheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.  Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationWadher, J. S., Puranik, M. P., Karande, N. A. & Yeole, P. G. (2009). J. PharmaTech Research 1, 22–33.  CAS Google Scholar
 First citationWestrip, S. P. (2010). J. Appl. Cryst. 43, 920–925.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 10| October 2012| Page o2990
https://doi.org/10.1107/S1600536812038354
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