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

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2,2′-[1,1′-(Hexane-1,6-diyldi­oxy­di­nitrilo)di­ethyl­­idyne]diphenol

aSchool of Chemical and Biological Engineering, Lanzhou Jiaotong University, Lanzhou 730070, People's Republic of China
*Correspondence e-mail: dongwk@mail.lzjtu.cn

(Received 18 July 2008; accepted 3 August 2008; online 9 August 2008)

The molecule of the title compound, C22H28N2O2, lies across an inversion centre with one half-mol­ecule in the asymmetric unit. The mol­ecule adopts an E configuration with respect to the azomethine C=N bond and the imino group is coplanar with the aromatic ring. Within the mol­ecule, the planar units are parallel, but extend in opposite directions from the hexa­methyl­ene bridge. There are intra­molecular O—H⋯N hydrogen bonds between the hydroxyl groups and the oxime N atoms. There are also weak inter­molecular C—H⋯O bonds that link each mol­ecule to two others, forming chains along the a axis.

Related literature

For related literature, see: Atwood (1997[Atwood, D. A. (1997). Coord. Chem. Rev. 165, 267-296.]); Canali & Sherrington (1999[Canali, L. & Sherrington, D. C. (1999). Chem. Soc. Rev. 28, 85-93.]); Dong et al. (2007[Dong, W. K., He, X. N., Dong, C. M., Wang, L., Zhong, J. K., Chen, X. & Yu, T. Z. (2007). Z. Kristallogr. New Cryst. Struct. 222, 289-290.], 2008a[Dong, W.-K., He, X.-N., Zhong, J.-K., Chen, X. & Yu, T.-Z. (2008a). Acta Cryst. E64, o1098.],b[Dong, W.-K., He, X.-N., Li, L., Lv, Z.-W. & Tong, J.-F. (2008b). Acta Cryst. E64, o1405.],c[Dong, W.-K., Zhao, C.-Y., Zhong, J.-K., Tang, X.-L. & Yu, T.-Z. (2008c). Acta Cryst. E64, o1323.]); Jarrahpour et al. (2004[Jarrahpour, A. A., Motamedifar, M., Pakshir, K., Hadi, N. & Zarei, M. (2004). 9, 815-824.]); Sun et al. (2004[Sun, S. S., Stern, C. L., Nguyen, S. T. & Hupp, J. T. (2004). J. Am. Chem. Soc. 126, 6314-6326.]); Venkataramanan et al. (2005[Venkataramanan, N. S., Kuppuraj, G. & Rajagopal, S. (2005). Coord. Chem. Rev. 249, 1249-1268.]); Wang et al. (2007[Wang, L., He, X., Sun, Y. & Xu, L. (2007). Acta Cryst. E63, o4517.]); Yu et al. (2008[Yu, T. Z., Zhang, K., Zhao, Y. L., Yang, C. H., Zhang, H., Qian, L., Fan, D. W., Dong, W. K., Chen, L. L. & Qiu, Y. Q. (2008). Inorg. Chim. Acta, 361, 233-240.]).

[Scheme 1]

Experimental

Crystal data
  • C22H28N2O4

  • Mr = 384.46

  • Monoclinic, C 2/c

  • a = 13.0052 (19) Å

  • b = 4.6441 (6) Å

  • c = 34.221 (3) Å

  • β = 95.000 (2)°

  • V = 2059.0 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 298 (2) K

  • 0.50 × 0.43 × 0.22 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.959, Tmax = 0.982

  • 4854 measured reflections

  • 1816 independent reflections

  • 1025 reflections with I > 2σ(I)

  • Rint = 0.081

Refinement
  • R[F2 > 2σ(F2)] = 0.066

  • wR(F2) = 0.185

  • S = 1.06

  • 1816 reflections

  • 127 parameters

  • H-atom parameters constrained

  • Δρmax = 0.15 e Å−3

  • Δρmin = −0.17 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2⋯N1 0.82 1.83 2.549 (3) 145
C4—H4B⋯O2i 0.96 2.70 3.476 (4) 138
C11—H11⋯O2i 0.93 2.69 3.587 (4) 163
Symmetry code: (i) [x+{\script{1\over 2}}, y-{\script{1\over 2}}, z].

Data collection: SMART (Siemens, 1996[Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); cell refinement: SMART; data reduction: SAINT (Siemens, 1996[Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Salen-type compounds have received a great deal of attention because of their versatility (Atwood et al., 1997; Yu et al., 2008; Venkataramanan et al., 2005). Some, along with their transition metal complexes, exhibit anticancer and anticoagulant activity (Sun et al., 2004) as well as antibacterial and antifungal properties (Jarrahpour et al., 2004). In addition, some of the salen-type species can be used as catalysts, especially in the area of asymmetric catalysis (Canali et al., 1999). Recently, we have reported the structures of a number molecules similar to the title compound (Wang et al., 2007; Dong et al., 2007, 2008a).

The title compound crystallized around a crystallographic inversion centre passing through the central C-C bond of the hexamethylene bridge (symmetry code: -x, -y, -z) to give 1/2 molecule per asymmetric unit (FIG. 1). It adopts an E configuration with respect to the azomethine C=N bond and the imino group is coplanar with the aromatic ring. Within the molecule, the planar units are parallel, but extend in opposite directions from the hexamethylene bridge. Intramolecular O(2)—H(2)···N(1) hydrogen bonds are found between the hydroxyl groups and the oxime N atoms (Table 1). This is similar to what was observed in our previously reported salen-type bisoxime compounds (Wang et al., 2007; Dong et al., 2007, 2008a).

In the unit cell there are also weak intermolecular C-H···O interactions that link each molecule to 2 others to form chains along the a axis (Table 1, Fig. 2), This differs from packing interactions found for 1,1'-[(hexane-1,6-diyldioxy)bis(nitrilomethylidyne)]dinaphthalene (Dong et al., 2008b) and 6,6'-dimethoxy-2,2'-[(hexane-1,6-diyldioxy)bis(nitrilomethylidyne)]diphenol (Dong et al., 2008c) in which the molecules exhibit three-dimensional supramolecular structures formed through strong intermolecular π-π stacking interactions or weak intermolecular hydrogen bonds.

Related literature top

For related literature, see: Atwood (1997); Canali & Sherrington (1999); Dong et al. (2007, 2008a,b,c); Jarrahpour et al. (2004); Sun et al. (2004); Venkataramanan et al. (2005); Wang et al. (2007); Yu et al. (2008).

Experimental top

The title compound was synthesized according to an analogous method reported earlier (Dong et al., 2007). To an ethanol solution (5 ml) of 2'-hydroxyacetophenone (561.4 mg, 4.00 mmol) was added an ethanol solution (4 ml) of 1,6-bis(aminooxy)hexane (296.5 mg, 2.00 mmol). The reaction mixture was stirred at 328 K for 4 h. The resulting precipitate was separated by filtration, and washed successively with ethanol and ethanol-hexane (1:4). The product was dried under vacuum to yield 434.0 mg of the title compound. Yield, 56.4%. mp. 343 K. Anal. Calc. for C22H28N2O2: C, 74.97; H, 8.01; N, 7.95. Found: C, 75.08; H, 7.85; N, 7.82.

Colorless block-shaped single crystals suitable for X-ray diffraction studies were obtained after several weeks by slow evaporation from an acetone solution.

Refinement top

Non-H atoms were refined anisotropically. H atoms were treated as riding atoms with distances C—H = 0.97 (CH2), 0.93 Å (CH), O—H = 0.82 Å and Uiso(H) = 1.2 Ueq(C) and 1.5 Ueq(O).

Computing details top

Data collection: SMART (Siemens, 1996); cell refinement: SMART (Siemens, 1996); data reduction: SAINT (Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with the atom numbering scheme [Symmetry codes: -x, -y + 2, -z + 1]. Displacement ellipsoids for non-hydrogen atoms are drawn at the 30% probability level.
[Figure 2] Fig. 2. Three-dimensional packing diagram of the title compound along the b axis. Intra- and intermolecular hydrogen bonds are shown as dashed lines.
2,2'-[1,1'-(Hexane-1,6-diyldioxydinitrilo)diethylidyne]diphenol top
Crystal data top
C22H28N2O4F(000) = 824
Mr = 384.46Dx = 1.240 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C -2ycCell parameters from 1018 reflections
a = 13.0052 (19) Åθ = 2.4–23.2°
b = 4.6441 (6) ŵ = 0.09 mm1
c = 34.221 (3) ÅT = 298 K
β = 95.000 (2)°Block-shaped, colorless
V = 2059.0 (4) Å30.50 × 0.43 × 0.22 mm
Z = 4
Data collection top
Bruker SMART CCD area-detector
diffractometer
1816 independent reflections
Radiation source: fine-focus sealed tube1025 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.081
ϕ and ω scansθmax = 25.0°, θmin = 2.4°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1215
Tmin = 0.959, Tmax = 0.982k = 55
4854 measured reflectionsl = 3640
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)] = 0.066Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.185H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.0707P)2 + 0.7764P]
where P = (Fo2 + 2Fc2)/3
1816 reflections(Δ/σ)max < 0.001
127 parametersΔρmax = 0.16 e Å3
0 restraintsΔρmin = 0.17 e Å3
Crystal data top
C22H28N2O4V = 2059.0 (4) Å3
Mr = 384.46Z = 4
Monoclinic, C2/cMo Kα radiation
a = 13.0052 (19) ŵ = 0.09 mm1
b = 4.6441 (6) ÅT = 298 K
c = 34.221 (3) Å0.50 × 0.43 × 0.22 mm
β = 95.000 (2)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
1816 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1025 reflections with I > 2σ(I)
Tmin = 0.959, Tmax = 0.982Rint = 0.081
4854 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0660 restraints
wR(F2) = 0.185H-atom parameters constrained
S = 1.06Δρmax = 0.16 e Å3
1816 reflectionsΔρmin = 0.17 e Å3
127 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
N10.20750 (18)0.7620 (6)0.39536 (6)0.0558 (7)
O10.25649 (15)0.9218 (5)0.42661 (6)0.0689 (7)
O20.04940 (15)0.5889 (6)0.35249 (6)0.0814 (8)
H20.08050.68180.37020.122*
C10.1805 (2)1.0874 (8)0.44434 (8)0.0634 (9)
H1A0.13801.18790.42400.076*
H1B0.21491.23100.46140.076*
C20.1115 (2)0.9044 (7)0.46802 (8)0.0568 (8)
H2A0.07120.77480.45050.068*
H2B0.15410.78850.48660.068*
C30.0392 (2)1.0874 (7)0.49000 (7)0.0545 (8)
H3A0.07961.20050.50960.065*
H3B0.00301.22020.47170.065*
C40.3827 (2)0.5826 (10)0.38989 (9)0.0837 (12)
H4A0.40840.76900.39800.126*
H4B0.41840.51600.36820.126*
H4C0.39380.44980.41130.126*
C50.2690 (2)0.6031 (7)0.37758 (8)0.0501 (7)
C60.2230 (2)0.4313 (7)0.34493 (7)0.0496 (7)
C70.1174 (2)0.4300 (8)0.33391 (8)0.0606 (8)
C80.0770 (3)0.2574 (9)0.30335 (9)0.0776 (10)
H80.00620.25740.29650.093*
C90.1397 (3)0.0870 (9)0.28307 (9)0.0786 (11)
H90.11160.02830.26260.094*
C100.2445 (3)0.0870 (8)0.29310 (9)0.0751 (10)
H100.28760.02780.27940.090*
C110.2846 (2)0.2562 (8)0.32321 (8)0.0626 (9)
H110.35560.25530.32960.075*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0568 (14)0.0595 (17)0.0530 (13)0.0017 (15)0.0155 (11)0.0068 (13)
O10.0583 (12)0.0827 (17)0.0685 (12)0.0034 (13)0.0215 (10)0.0199 (12)
O20.0554 (13)0.093 (2)0.0976 (16)0.0061 (14)0.0143 (12)0.0252 (15)
C10.0693 (19)0.059 (2)0.0651 (17)0.0062 (18)0.0267 (15)0.0163 (16)
C20.0571 (17)0.056 (2)0.0589 (16)0.0034 (17)0.0163 (13)0.0037 (16)
C30.0593 (17)0.0524 (19)0.0535 (16)0.0009 (16)0.0144 (13)0.0038 (15)
C40.0543 (19)0.108 (3)0.089 (2)0.011 (2)0.0101 (16)0.027 (2)
C50.0506 (16)0.0483 (18)0.0542 (15)0.0036 (15)0.0202 (13)0.0017 (15)
C60.0562 (17)0.0486 (18)0.0464 (14)0.0036 (16)0.0172 (12)0.0078 (14)
C70.0634 (19)0.059 (2)0.0610 (18)0.0055 (18)0.0157 (15)0.0015 (17)
C80.077 (2)0.079 (3)0.077 (2)0.004 (2)0.0061 (18)0.007 (2)
C90.108 (3)0.070 (3)0.0583 (19)0.003 (2)0.008 (2)0.0042 (18)
C100.107 (3)0.064 (2)0.0571 (19)0.019 (2)0.0239 (18)0.0010 (18)
C110.074 (2)0.061 (2)0.0547 (17)0.012 (2)0.0190 (15)0.0036 (17)
Geometric parameters (Å, º) top
N1—C51.281 (3)C4—H4A0.9600
N1—O11.408 (3)C4—H4B0.9600
O1—C11.429 (3)C4—H4C0.9600
O2—C71.352 (4)C5—C61.458 (4)
O2—H20.8200C6—C71.393 (4)
C1—C21.520 (4)C6—C111.399 (4)
C1—H1A0.9700C7—C81.384 (5)
C1—H1B0.9700C8—C91.368 (5)
C2—C31.515 (4)C8—H80.9300
C2—H2A0.9700C9—C101.376 (5)
C2—H2B0.9700C9—H90.9300
C3—C3i1.512 (5)C10—C111.363 (5)
C3—H3A0.9700C10—H100.9300
C3—H3B0.9700C11—H110.9300
C4—C51.504 (4)
C5—N1—O1113.9 (2)C5—C4—H4C109.5
N1—O1—C1108.8 (2)H4A—C4—H4C109.5
C7—O2—H2109.5H4B—C4—H4C109.5
O1—C1—C2112.8 (3)N1—C5—C6116.6 (2)
O1—C1—H1A109.0N1—C5—C4122.9 (3)
C2—C1—H1A109.0C6—C5—C4120.5 (3)
O1—C1—H1B109.0C7—C6—C11116.8 (3)
C2—C1—H1B109.0C7—C6—C5122.6 (3)
H1A—C1—H1B107.8C11—C6—C5120.6 (3)
C3—C2—C1111.8 (2)O2—C7—C8116.8 (3)
C3—C2—H2A109.3O2—C7—C6122.7 (3)
C1—C2—H2A109.3C8—C7—C6120.5 (3)
C3—C2—H2B109.3C9—C8—C7120.9 (3)
C1—C2—H2B109.3C9—C8—H8119.5
H2A—C2—H2B107.9C7—C8—H8119.5
C3i—C3—C2113.3 (3)C8—C9—C10119.6 (3)
C3i—C3—H3A108.9C8—C9—H9120.2
C2—C3—H3A108.9C10—C9—H9120.2
C3i—C3—H3B108.9C11—C10—C9119.6 (3)
C2—C3—H3B108.9C11—C10—H10120.2
H3A—C3—H3B107.7C9—C10—H10120.2
C5—C4—H4A109.5C10—C11—C6122.5 (3)
C5—C4—H4B109.5C10—C11—H11118.8
H4A—C4—H4B109.5C6—C11—H11118.8
C5—N1—O1—C1179.4 (2)C5—C6—C7—O20.3 (5)
N1—O1—C1—C272.4 (3)C11—C6—C7—C81.3 (5)
O1—C1—C2—C3173.9 (2)C5—C6—C7—C8178.3 (3)
C1—C2—C3—C3i173.2 (3)O2—C7—C8—C9179.4 (3)
O1—N1—C5—C6179.9 (2)C6—C7—C8—C90.7 (5)
O1—N1—C5—C41.9 (4)C7—C8—C9—C100.1 (5)
N1—C5—C6—C71.9 (4)C8—C9—C10—C110.2 (5)
C4—C5—C6—C7176.1 (3)C9—C10—C11—C60.5 (5)
N1—C5—C6—C11178.5 (3)C7—C6—C11—C101.2 (4)
C4—C5—C6—C113.4 (4)C5—C6—C11—C10178.4 (3)
C11—C6—C7—O2179.9 (3)
Symmetry code: (i) x, y+2, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···N10.821.832.549 (3)145
C4—H4B···O2ii0.962.703.476 (4)138
C11—H11···O2ii0.932.693.587 (4)163
Symmetry code: (ii) x+1/2, y1/2, z.

Experimental details

Crystal data
Chemical formulaC22H28N2O4
Mr384.46
Crystal system, space groupMonoclinic, C2/c
Temperature (K)298
a, b, c (Å)13.0052 (19), 4.6441 (6), 34.221 (3)
β (°) 95.000 (2)
V3)2059.0 (4)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.50 × 0.43 × 0.22
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.959, 0.982
No. of measured, independent and
observed [I > 2σ(I)] reflections
4854, 1816, 1025
Rint0.081
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.066, 0.185, 1.06
No. of reflections1816
No. of parameters127
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.16, 0.17

Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···N10.821.832.549 (3)145.0
C4—H4B···O2i0.962.703.476 (4)138.3
C11—H11···O2i0.932.693.587 (4)163.0
Symmetry code: (i) x+1/2, y1/2, z.
 

Acknowledgements

This work was supported by the Foundation of the Education Department of Gansu Province (No. 0604–01) and the `Qing Lan' Talent Engineering Funds of Lanzhou Jiaotong University (No. QL-03–01 A), which are gratefully acknowledged.

References

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