2-[4-(2-Formyl­phen­oxy)­but­oxy]­benzaldehyde

Abstract

In the crystal structure of the title compound, C₁₈H₁₈O₄, the full mol­ecule is generated by the application of an inversion centre. The mol­ecule is essentially planar, with an r.m.s. deviation of 0.017 (1) Å for all non-H atoms. The mol­ecules are linked through inter­molecular C—H⋯O inter­actions to form a mol­ecular sheet parallel to the (02) plane.

Related literature

For the synthesis and related structures, see: Hu et al. (2005 ▶); Aravindan et al. (2003 ▶). For related literature on Schiff bases and their transition metal complexes, see: Ilhan et al. (2009 ▶, 2010 ▶); Yilmaz et al. (2009 ▶).

Experimental

Crystal data

• C₁₈H₁₈O₄

• M _r = 298.34

• Monoclinic,

• a = 8.0624 (7) Å

• b = 14.5896 (7) Å

• c = 6.8003 (4) Å

• β = 108.549 (4)°

• V = 758.35 (8) ų

• Z = 2

• Mo Kα radiation

• μ = 0.09 mm⁻¹

• T = 190 K

• 0.30 × 0.24 × 0.15 mm

Data collection

• Rigaku R-AXIS RAPID II diffractometer

• Absorption correction: numerical (NUMABS; Higashi, 1999 ▶) T _min = 0.980, T _max = 0.986

• 12149 measured reflections

• 2210 independent reflections

• 1243 reflections with I > 2σ(I)

• R _int = 0.041

Refinement

• R[F ² > 2σ(F ²)] = 0.044

• wR(F ²) = 0.132

• S = 1.13

• 2210 reflections

• 100 parameters

• H-atom parameters constrained

• Δρ_max = 0.29 e Å⁻³

• Δρ_min = −0.24 e Å⁻³

Data collection: PROCESS-AUTO (Rigaku/MSC, 2004 ▶); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 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: CrystalStructure and PLATON (Spek, 2009 ▶).

Supplementary Material

Supplementary material file. DOI: 10.1107/S1600536811034210/tk2783Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C3—H3⋯O1i	0.95	2.53	3.397 (2)	152

Symmetry code: (i) .

supplementary crystallographic information

Comment

In recent years, much attention has been paid to the synthesis and coordination chemistry of salicylaldehyde, its Schiff base derivatives and transition metal complexes (Hu et al., 2005; Aravindan et al., 2003; Ilhan et al., 2009, 2010; Yilmaz et al., 2009). The two-arm aldehydes can be condensed with primary diamines to form macrocyclic Schiff base ligands (Ilhan et al., 2009, 2010; Yilmaz et al., 2009).

In the crystal structure, the title molecule, 2,2'-[butane-1,4-diylbis(oxy)]dibenzaldehyde (Fig. 1), lies on a crystallographic inversion center, thus indicating that one half the molecule comprises the asymmetric unit. The molecules are linked through intermolecular C3—H3···O1ⁱⁱ contacts (Table 1), resulting in a molecular sheet parallel to the (102) plane (Fig. 2).

Experimental

The title compound was isolated from the reaction between salicylaldehyde and butane-1,4-diamine in the presence of K₂CO₃ at 85 °C for about 48 h according to the literature (Hu et al., 2005). A small amount of the precipitate was dissolved in a mixture of methanol-chloroform (1:1 v/v) to make a clear solution and kept at room temperature for 3 days to give single crystals suitable for X-ray diffraction.

Refinement

All H atoms were positioned geometrically (C—H = 0.95 or 0.99 Å) and were refined as riding, with U_iso(H) = 1.2U_eq(C).

Figures

Fig. 1.

The molecular structure of the title compound, showing the atom-numbering scheme. Displacement ellipsoids of non-H atoms are drawn at the 50% probability level.

Fig. 2.

A packing diagram of the title compound, showing a molecular sheet formed by C—H···O hydrogen bonds (dashed lines).

Crystal data

C18H18O4	F(000) = 316.00
Mr = 298.34	Dx = 1.306 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71075 Å
Hall symbol: -P 2ybc	Cell parameters from 7072 reflections
a = 8.0624 (7) Å	θ = 3.0–30.1°
b = 14.5896 (7) Å	µ = 0.09 mm−1
c = 6.8003 (4) Å	T = 190 K
β = 108.549 (4)°	Block, pale-yellow
V = 758.35 (8) Å3	0.30 × 0.24 × 0.15 mm
Z = 2

Data collection

Rigaku R-AXIS RAPID II diffractometer	1243 reflections with I > 2σ(I)
Detector resolution: 10.00 pixels mm-1	Rint = 0.041
ω scans	θmax = 30.0°
Absorption correction: numerical (NUMABS; Higashi, 1999)	h = −11→11
Tmin = 0.980, Tmax = 0.986	k = −20→20
12149 measured reflections	l = −9→9
2210 independent reflections

Refinement

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)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.132	H-atom parameters constrained
S = 1.13	w = 1/[σ2(Fo2) + (0.0563P)2 + 0.0806P] where P = (Fo2 + 2Fc2)/3
2210 reflections	(Δ/σ)max = 0.0001
100 parameters	Δρmax = 0.29 e Å−3
0 restraints	Δρmin = −0.24 e Å−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.18122 (15)	0.33844 (8)	0.1640 (2)	0.0554 (4)
O2	0.69626 (12)	0.36790 (7)	0.37956 (16)	0.0343 (3)
C1	0.45915 (17)	0.26677 (9)	0.2840 (2)	0.0307 (3)
C2	0.64045 (18)	0.27981 (9)	0.3598 (2)	0.0297 (3)
C3	0.75273 (18)	0.20492 (10)	0.4082 (2)	0.0327 (3)
H3	0.8758	0.2135	0.4596	0.039*
C4	0.6825 (2)	0.11807 (10)	0.3803 (2)	0.0380 (4)
H4	0.7586	0.0666	0.4134	0.046*
C5	0.5042 (2)	0.10385 (11)	0.3054 (3)	0.0411 (4)
H5	0.4582	0.0434	0.2868	0.049*
C6	0.3940 (2)	0.17801 (10)	0.2582 (2)	0.0380 (4)
H6	0.2712	0.1684	0.2071	0.046*
C7	0.3391 (2)	0.34439 (11)	0.2358 (3)	0.0396 (4)
H7	0.3882	0.4041	0.2625	0.047*
C8	0.88087 (17)	0.38476 (10)	0.4570 (2)	0.0333 (3)
H8A	0.9405	0.3547	0.3674	0.040*
H8B	0.9307	0.3604	0.5996	0.040*
C9	0.90444 (18)	0.48669 (10)	0.4558 (2)	0.0350 (4)
H9A	0.8379	0.5159	0.5387	0.042*
H9B	0.8568	0.5096	0.3117	0.042*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
O1	0.0243 (6)	0.0575 (8)	0.0782 (9)	0.0011 (5)	0.0074 (6)	−0.0063 (6)
O2	0.0210 (5)	0.0285 (5)	0.0497 (6)	−0.0040 (4)	0.0060 (4)	−0.0021 (4)
C1	0.0234 (7)	0.0324 (8)	0.0352 (7)	−0.0038 (5)	0.0077 (6)	−0.0030 (6)
C2	0.0268 (7)	0.0287 (7)	0.0333 (7)	−0.0051 (5)	0.0092 (6)	−0.0032 (6)
C3	0.0244 (7)	0.0320 (8)	0.0391 (8)	−0.0013 (6)	0.0065 (6)	−0.0020 (6)
C4	0.0358 (8)	0.0316 (8)	0.0447 (9)	0.0011 (6)	0.0102 (7)	0.0001 (7)
C5	0.0363 (8)	0.0317 (8)	0.0521 (9)	−0.0074 (6)	0.0095 (7)	−0.0039 (7)
C6	0.0286 (8)	0.0388 (9)	0.0441 (9)	−0.0085 (6)	0.0081 (7)	−0.0055 (7)
C7	0.0265 (8)	0.0372 (9)	0.0529 (10)	−0.0018 (6)	0.0095 (7)	−0.0027 (7)
C8	0.0206 (7)	0.0313 (7)	0.0453 (8)	−0.0026 (5)	0.0068 (6)	−0.0035 (6)
C9	0.0239 (7)	0.0294 (7)	0.0489 (9)	−0.0023 (6)	0.0075 (6)	−0.0035 (6)

Geometric parameters (Å, °)

O1—C7	1.2128 (18)	C5—C6	1.372 (2)
O2—C2	1.3543 (16)	C5—H5	0.9500
O2—C8	1.4333 (16)	C6—H6	0.9500
C1—C6	1.3874 (19)	C7—H7	0.9500
C1—C2	1.3997 (19)	C8—C9	1.500 (2)
C1—C7	1.458 (2)	C8—H8A	0.9900
C2—C3	1.390 (2)	C8—H8B	0.9900
C3—C4	1.376 (2)	C9—C9i	1.516 (3)
C3—H3	0.9500	C9—H9A	0.9900
C4—C5	1.379 (2)	C9—H9B	0.9900
C4—H4	0.9500
C2—O2—C8	118.21 (11)	C5—C6—H6	119.5
C6—C1—C2	118.83 (13)	C1—C6—H6	119.5
C6—C1—C7	119.95 (13)	O1—C7—C1	124.87 (14)
C2—C1—C7	121.21 (12)	O1—C7—H7	117.6
O2—C2—C3	123.48 (13)	C1—C7—H7	117.6
O2—C2—C1	116.14 (12)	O2—C8—C9	106.66 (11)
C3—C2—C1	120.37 (12)	O2—C8—H8A	110.4
C4—C3—C2	118.85 (13)	C9—C8—H8A	110.4
C4—C3—H3	120.6	O2—C8—H8B	110.4
C2—C3—H3	120.6	C9—C8—H8B	110.4
C3—C4—C5	121.62 (14)	H8A—C8—H8B	108.6
C3—C4—H4	119.2	C8—C9—C9i	111.50 (15)
C5—C4—H4	119.2	C8—C9—H9A	109.3
C6—C5—C4	119.28 (14)	C9i—C9—H9A	109.3
C6—C5—H5	120.4	C8—C9—H9B	109.3
C4—C5—H5	120.4	C9i—C9—H9B	109.3
C5—C6—C1	121.05 (14)	H9A—C9—H9B	108.0
C8—O2—C2—C3	−0.8 (2)	C3—C4—C5—C6	−0.2 (2)
C8—O2—C2—C1	179.88 (12)	C4—C5—C6—C1	0.2 (2)
C6—C1—C2—O2	179.34 (12)	C2—C1—C6—C5	−0.1 (2)
C7—C1—C2—O2	−1.8 (2)	C7—C1—C6—C5	−179.02 (15)
C6—C1—C2—C3	0.0 (2)	C6—C1—C7—O1	−3.4 (3)
C7—C1—C2—C3	178.91 (14)	C2—C1—C7—O1	177.73 (16)
O2—C2—C3—C4	−179.30 (13)	C2—O2—C8—C9	178.18 (12)
C1—C2—C3—C4	0.0 (2)	O2—C8—C9—C9i	177.46 (15)
C2—C3—C4—C5	0.1 (2)

Symmetry codes: (i) −x+2, −y+1, −z+1.

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O1ii	0.95	2.53	3.397 (2)	152

Symmetry codes: (ii) x+1, −y+1/2, z+1/2.