2,2′-[1,1′-(Octane-1,8-diyldioxy­dinitrilo)diethyl­idyne]diphenol

Dong, W.-K.; Tong, J.-F.; Yao, J.; Gong, S.-S.; Wu, J.-C.

doi:10.1107/S1600536809033959

organic compounds

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ISSN: 2056-9890

Volume 65| Part 10| October 2009| Page o2311

doi:10.1107/S1600536809033959

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2,2′-[1,1′-(Octane-1,8-diyldioxydinitrilo)diethylidyne]diphenol

Wen-Kui Dong,^a ^* Jun-Feng Tong,^a Jian Yao,^a Shang-Sheng Gong ^a and Jian-Chao Wu ^a

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

(Received 13 August 2009; accepted 25 August 2009; online 5 September 2009)

The title compound, C₂₄H₃₂N₂O₄, has a crystallographic inversion centre at the mid-point of the central C—C bond. At each end of the molecule, intramolecular O—H⋯N hydrogen bonds generate six-membered S(6) ring motifs. The crystal structure is stabilized by pairs of weak intermolecular C—H⋯O hydrogen bonds that link neighbouring molecules into R₂²(40) ring motifs, which in turn form infinite one-dimensional supramolecular ribbon structures.

Related literature

For background to oxime-based salen-type tetradentate ligands, see: Akine et al. (2005 ); Dong, He et al. (2009 ); Dong, Sun et al. (2009 ). For the synthesis, see: Dong et al. (2008 ). For related structures, see: Dong, Zhao et al. (2009 ); Etemadi et al. (2009 ). For information relating to C—H⋯O hydrogen bonds, see: Desiraju (1996 ). For graph-set notation, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₂₄H₃₂N₂O₄
M_r = 412.52
Monoclinic, C 2/c
a = 12.9524 (12) Å
b = 4.6667 (6) Å
c = 37.722 (3) Å
β = 99.379 (2)°
V = 2249.6 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 298 K
0.50 × 0.48 × 0.20 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.960, T_max = 0.984
5371 measured reflections
1979 independent reflections
1172 reflections with I > 2σ(I)
R_int = 0.069

Refinement

R[F² > 2σ(F²)] = 0.074
wR(F²) = 0.173
S = 1.11
1979 reflections
137 parameters
H-atom parameters constrained
Δρ_max = 0.20 e Å⁻³
Δρ_min = −0.21 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2⋯N1	0.82	1.84	2.558 (4)	145
C12—H12⋯O2ⁱ	0.93	2.64	3.544 (5)	164
Symmetry code: (i) $[x-{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ .

Data collection: SMART (Siemens, 1996 ); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809033959/pk2184sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809033959/pk2184Isup2.hkl

checkCIF report

Comment top

Much attention has been focused on oxime-based salen-type tetradentate ligands in recent years due to their high stability against imine metathesis reactions (Akine et al., 2005; Dong, He et al. 2009). A number of their metal complexes have been prepared and reported (Dong, Sun et al. 2009), which demonstrates that bisoxime ligands have strong coordinating ability with transition metals and non-transition metals. In continuation of our previously reported works (Dong, Zhao et al. 2009), here we report synthesis and structure of salen-type bisoxime ligands, 2,2'-[1,1'-(octane-1,8-diyldioxydinitrilo)diethylidyne]diphenol.

The molecular structure of the title compound, as shown in Fig. 1, has a crystallographic inversion centre at the mid-point of the the central C—C bond. Thus there is half a molecule in the asymmetric unit. The two benzene rings are parallel to each other with a perpendicular interplanar spacing of ca 5.316 (2) Å. In each molecule, there exist two intramolecular O—H···N hydrogen bonds, that form two S(6) ring motifs (Fig. 1) (Bernstein et al., 1995). Pairs of weak intermolecular C—H···O hydrogen bonds (Desiraju, 1996) link neighbouring molecules into an infinite one-dimensional supramolecular structure with R₂²(40) ring motifs (Table 1, Fig. 2), similar to that described by Etemadi et al., (2009).

Related literature top

For background to oxime-based salen-type tetradentate ligands, see: Akine et al. (2005); Dong, He et al. (2009); Dong, Sun et al. (2009). For the synthesis, see: Dong et al. (2008). For related structures, see: Dong, Zhao et al. (2009); Etemadi et al. (2009). For information relating to C—H···O hydrogen bonds, see: Desiraju (1996). For graph-set notation, see: Bernstein et al. (1995).

Experimental top

2,2'-[1,1'-(Octane-1,8-diyldioxydinitrilo)diethylidyne]diphenol was synthesized according to our previous work (Dong et al., 2008). To an ethanol solution (4 ml) of 2'-hydroxyacetophenone (280.7 mg, 2.06 mmol) was added an ethanol solution (4 ml) of 1, 8-bis(aminooxy)octane (180.9 mg, 1.03 mmol). The mixture was stirred at 328–333 K for 48 h. When cooled to room temperature, the resulting white precipitate was filtered, and washed successively with ethanol and n-hexane. The product was dried under vacuum and purified by recrystallization from ethanol to yield 206.5 mg of the title compound. Yield, 49.01%. m. p. 345–347 K. Anal. Calcd. for C₂₄H₃₂N₂O₄: C, 69.88; H, 7.82; N, 6.79. Found: C, 69.50; H, 7.53; N, 6.87.

Colorless block-like single crystals suitable for X-ray diffraction studies were obtained after several days by slow evaporation from a diethyl ether solution.

Computing details top

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (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) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Unlabelled atoms are related to their labelled counterparts by the inversion operation [-x + 3/2,-y + 3/2,-z + 1]. Displacement ellipsoids for non-hydrogen atoms are drawn at the 30% probability level.
	Fig. 2. Part of the one-dimensional supramolecular structure of the title compound. Intramolecular and intermolecular hydrogen bonds are shown as dashed lines. Colour code: dark gray: C; red: O; blue: N; pale green: H (Macrae et al., 2006).

2,2'-[1,1'-(Octane-1,8-diyldioxydinitrilo)diethylidyne]diphenol top

Crystal data top

C₂₄H₃₂N₂O₄	F(000) = 888
M_r = 412.52	D_x = 1.218 Mg m⁻³
Monoclinic, C2/c	Melting point = 345–347 K
Hall symbol: -C 2yc	Mo Kα radiation, λ = 0.71073 Å
a = 12.9524 (12) Å	Cell parameters from 1491 reflections
b = 4.6667 (6) Å	θ = 2.2–27.2°
c = 37.722 (3) Å	µ = 0.08 mm⁻¹
β = 99.379 (2)°	T = 298 K
V = 2249.6 (4) Å³	Block-like, colorless
Z = 4	0.50 × 0.48 × 0.20 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	1979 independent reflections
Radiation source: fine-focus sealed tube	1172 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.069
ϕ and ω scans	θ_max = 25.0°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −14→15
T_min = 0.960, T_max = 0.984	k = −5→5
5371 measured reflections	l = −37→44

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.074	H-atom parameters constrained
wR(F²) = 0.173	w = 1/[σ²(F_o²) + (0.0225P)² + 4.9486P] where P = (F_o² + 2F_c²)/3
S = 1.11	(Δ/σ)_max < 0.001
1979 reflections	Δρ_max = 0.20 e Å⁻³
137 parameters	Δρ_min = −0.21 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0080 (9)

Crystal data top

C₂₄H₃₂N₂O₄	V = 2249.6 (4) Å³
M_r = 412.52	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 12.9524 (12) Å	µ = 0.08 mm⁻¹
b = 4.6667 (6) Å	T = 298 K
c = 37.722 (3) Å	0.50 × 0.48 × 0.20 mm
β = 99.379 (2)°

Data collection top

Bruker SMART CCD area-detector diffractometer	1979 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	1172 reflections with I > 2σ(I)
T_min = 0.960, T_max = 0.984	R_int = 0.069
5371 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.074	0 restraints
wR(F²) = 0.173	H-atom parameters constrained
S = 1.11	Δρ_max = 0.20 e Å⁻³
1979 reflections	Δρ_min = −0.21 e Å⁻³
137 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

	x	y	z	U_iso*/U_eq
N1	0.3869 (2)	0.5102 (7)	0.38238 (7)	0.0490 (8)
O1	0.35769 (17)	0.6700 (6)	0.41082 (6)	0.0617 (8)
O2	0.51778 (18)	0.3352 (7)	0.34323 (7)	0.0746 (9)
H2	0.4980	0.4288	0.3593	0.112*
C1	0.4459 (3)	0.8346 (9)	0.42728 (9)	0.0570 (10)
H1A	0.4224	0.9786	0.4427	0.068*
H1B	0.4757	0.9335	0.4087	0.068*
C2	0.5297 (2)	0.6538 (9)	0.44922 (9)	0.0513 (9)
H2A	0.5594	0.5254	0.4333	0.062*
H2B	0.4983	0.5377	0.4659	0.062*
C3	0.6162 (2)	0.8345 (9)	0.46995 (9)	0.0518 (9)
H3A	0.5870	0.9513	0.4872	0.062*
H3B	0.6430	0.9627	0.4534	0.062*
C4	0.7063 (2)	0.6595 (9)	0.48983 (9)	0.0540 (10)
H4A	0.6796	0.5333	0.5067	0.065*
H4B	0.7347	0.5406	0.4727	0.065*
C5	0.3132 (2)	0.3491 (8)	0.36639 (8)	0.0440 (9)
C6	0.2085 (3)	0.3295 (12)	0.37779 (11)	0.0786 (14)
H6A	0.1970	0.1371	0.3852	0.118*
H6B	0.1552	0.3805	0.3580	0.118*
H6C	0.2059	0.4585	0.3975	0.118*
C7	0.3382 (2)	0.1742 (8)	0.33664 (8)	0.0447 (9)
C8	0.4372 (3)	0.1723 (9)	0.32643 (10)	0.0547 (10)
C9	0.4582 (3)	0.0008 (10)	0.29864 (11)	0.0699 (12)
H9	0.5247	0.0013	0.2924	0.084*
C10	0.3815 (4)	−0.1708 (10)	0.28013 (10)	0.0714 (12)
H10	0.3961	−0.2862	0.2615	0.086*
C11	0.2835 (4)	−0.1710 (10)	0.28930 (10)	0.0699 (12)
H11	0.2313	−0.2859	0.2767	0.084*
C12	0.2619 (3)	−0.0026 (9)	0.31692 (9)	0.0587 (11)
H12	0.1948	−0.0054	0.3228	0.070*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0372 (16)	0.058 (2)	0.0459 (16)	0.0005 (15)	−0.0117 (12)	−0.0031 (17)
O1	0.0381 (14)	0.081 (2)	0.0591 (15)	0.0022 (14)	−0.0132 (11)	−0.0207 (16)
O2	0.0399 (14)	0.092 (2)	0.0886 (19)	−0.0111 (16)	0.0020 (13)	−0.0267 (19)
C1	0.044 (2)	0.061 (2)	0.057 (2)	0.001 (2)	−0.0190 (16)	−0.017 (2)
C2	0.0416 (19)	0.060 (2)	0.0460 (19)	−0.0056 (19)	−0.0126 (15)	−0.001 (2)
C3	0.0413 (19)	0.060 (2)	0.0483 (19)	−0.002 (2)	−0.0097 (15)	−0.012 (2)
C4	0.0395 (19)	0.061 (2)	0.056 (2)	−0.004 (2)	−0.0099 (15)	−0.009 (2)
C5	0.0320 (18)	0.050 (2)	0.0437 (18)	−0.0007 (17)	−0.0128 (14)	0.0062 (19)
C6	0.045 (2)	0.108 (4)	0.080 (3)	−0.017 (3)	0.0029 (19)	−0.024 (3)
C7	0.0380 (19)	0.046 (2)	0.0433 (18)	−0.0042 (17)	−0.0124 (14)	0.0072 (18)
C8	0.050 (2)	0.054 (2)	0.055 (2)	−0.001 (2)	−0.0078 (17)	−0.003 (2)
C9	0.061 (3)	0.080 (3)	0.067 (3)	0.002 (3)	0.005 (2)	−0.003 (3)
C10	0.092 (3)	0.068 (3)	0.051 (2)	0.005 (3)	0.001 (2)	−0.002 (2)
C11	0.083 (3)	0.066 (3)	0.051 (2)	−0.019 (3)	−0.016 (2)	0.003 (2)
C12	0.055 (2)	0.064 (3)	0.051 (2)	−0.012 (2)	−0.0112 (17)	0.009 (2)

Geometric parameters (Å, º) top

N1—C5	1.285 (4)	C4—H4B	0.9700
N1—O1	1.408 (3)	C5—C7	1.466 (5)
O1—C1	1.432 (4)	C5—C6	1.491 (5)
O2—C8	1.361 (4)	C6—H6A	0.9600
O2—H2	0.8200	C6—H6B	0.9600
C1—C2	1.511 (5)	C6—H6C	0.9600
C1—H1A	0.9700	C7—C8	1.398 (5)
C1—H1B	0.9700	C7—C12	1.404 (5)
C2—C3	1.514 (5)	C8—C9	1.380 (5)
C2—H2A	0.9700	C9—C10	1.375 (6)
C2—H2B	0.9700	C9—H9	0.9300
C3—C4	1.518 (5)	C10—C11	1.369 (5)
C3—H3A	0.9700	C10—H10	0.9300
C3—H3B	0.9700	C11—C12	1.370 (5)
C4—C4ⁱ	1.517 (6)	C11—H11	0.9300
C4—H4A	0.9700	C12—H12	0.9300

C5—N1—O1	113.3 (3)	N1—C5—C7	116.5 (3)
N1—O1—C1	108.7 (3)	N1—C5—C6	122.8 (3)
C8—O2—H2	109.5	C7—C5—C6	120.7 (3)
O1—C1—C2	112.9 (3)	C5—C6—H6A	109.5
O1—C1—H1A	109.0	C5—C6—H6B	109.5
C2—C1—H1A	109.0	H6A—C6—H6B	109.5
O1—C1—H1B	109.0	C5—C6—H6C	109.5
C2—C1—H1B	109.0	H6A—C6—H6C	109.5
H1A—C1—H1B	107.8	H6B—C6—H6C	109.5
C1—C2—C3	112.1 (3)	C8—C7—C12	116.7 (3)
C1—C2—H2A	109.2	C8—C7—C5	122.7 (3)
C3—C2—H2A	109.2	C12—C7—C5	120.6 (3)
C1—C2—H2B	109.2	O2—C8—C9	116.5 (4)
C3—C2—H2B	109.2	O2—C8—C7	122.4 (3)
H2A—C2—H2B	107.9	C9—C8—C7	121.0 (4)
C2—C3—C4	113.6 (3)	C10—C9—C8	120.5 (4)
C2—C3—H3A	108.8	C10—C9—H9	119.7
C4—C3—H3A	108.8	C8—C9—H9	119.7
C2—C3—H3B	108.8	C11—C10—C9	119.7 (4)
C4—C3—H3B	108.8	C11—C10—H10	120.2
H3A—C3—H3B	107.7	C9—C10—H10	120.2
C4ⁱ—C4—C3	113.6 (4)	C10—C11—C12	120.3 (4)
C4ⁱ—C4—H4A	108.8	C10—C11—H11	119.9
C3—C4—H4A	108.8	C12—C11—H11	119.9
C4ⁱ—C4—H4B	108.8	C11—C12—C7	121.8 (4)
C3—C4—H4B	108.8	C11—C12—H12	119.1
H4A—C4—H4B	107.7	C7—C12—H12	119.1

C5—N1—O1—C1	178.4 (3)	C12—C7—C8—O2	179.6 (3)
N1—O1—C1—C2	−72.6 (4)	C5—C7—C8—O2	−0.6 (6)
O1—C1—C2—C3	−173.2 (3)	C12—C7—C8—C9	−1.0 (5)
C1—C2—C3—C4	−175.1 (3)	C5—C7—C8—C9	178.8 (3)
C2—C3—C4—C4ⁱ	179.2 (4)	O2—C8—C9—C10	−180.0 (4)
O1—N1—C5—C7	−179.5 (3)	C7—C8—C9—C10	0.6 (6)
O1—N1—C5—C6	−1.6 (5)	C8—C9—C10—C11	0.1 (6)
N1—C5—C7—C8	2.0 (5)	C9—C10—C11—C12	−0.4 (6)
C6—C5—C7—C8	−176.0 (4)	C10—C11—C12—C7	0.0 (6)
N1—C5—C7—C12	−178.2 (3)	C8—C7—C12—C11	0.7 (5)
C6—C5—C7—C12	3.8 (5)	C5—C7—C12—C11	−179.1 (4)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···N1	0.82	1.84	2.558 (4)	145
C12—H12···O2ⁱⁱ	0.93	2.64	3.544 (5)	164

Symmetry code: (ii) x−1/2, y−1/2, z.

Experimental details

Crystal data
Chemical formula	C₂₄H₃₂N₂O₄
M_r	412.52
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	298
a, b, c (Å)	12.9524 (12), 4.6667 (6), 37.722 (3)
β (°)	99.379 (2)
V (Å³)	2249.6 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.50 × 0.48 × 0.20

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.960, 0.984
No. of measured, independent and observed [I > 2σ(I)] reflections	5371, 1979, 1172
R_int	0.069
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.074, 0.173, 1.11
No. of reflections	1979
No. of parameters	137
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.20, −0.21

Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···N1	0.82	1.84	2.558 (4)	145.2
C12—H12···O2ⁱ	0.93	2.64	3.544 (5)	164.0

Symmetry code: (i) x−1/2, y−1/2, z.

Acknowledgements

This work was supported by the Foundation of the Education Department of Gansu Province (No. 0904–11) and the `Jing Lan' Talent Engineering Funds of Lanzhou Jiaotong University, which are gratefully acknowledged.

References

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