2,2'-Diisopropoxy-5,5'-methyl-enedi-benz-alde-hyde.

Mol-ecules of the title compound, C(21)H(24)O(4), are located on a twofold rotation axis running through the central methyl-ene C atom. The aldehyde group is coplanar with the benzene ring [C-C-C-O = 175.7 (4) °].

Related literature

For related salicyl­aldehyde compounds, see: Qiu et al. (2009 ▶); Yu et al. (2007 ▶); Wang et al. (2009 ▶).

Experimental

Crystal data

C21H24O4

M = 340.40

Orthorhombic,

a = 26.337 (9) Å

b = 28.349 (10) Å

c = 4.990 (2) Å

V = 3726 (2) Å3

Z = 8

Mo Kα radiation

μ = 0.08 mm−1

T = 293 K

0.35 × 0.25 × 0.20 mm

Data collection

Bruker SMART APEXII area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2008 ▶) T min = 0.972, T max = 0.984

4329 measured reflections

1022 independent reflections

886 reflections with I > 2σ(I)

R int = 0.035

Refinement

R[F 2 > 2σ(F 2)] = 0.040

wR(F 2) = 0.114

S = 1.06

1022 reflections

114 parameters

1 restraint

H-atom parameters constrained

Δρmax = 0.17 e Å−3

Δρmin = −0.13 e Å−3

Data collection: APEX2 (Bruker, 2008 ▶); cell refinement: SAINT (Bruker, 2008 ▶); data reduction: SAINT; 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 and PLATON (Spek, 2009 ▶).

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812028048/bt5945sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812028048/bt5945Isup2.hkl

Supplementary material file. DOI: 10.1107/S1600536812028048/bt5945Isup3.cml

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

C21H24O4	F(000) = 1456
Mr = 340.40	Dx = 1.214 Mg m−3
Orthorhombic, Fdd2	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: F 2 -2d	Cell parameters from 1022 reflections
a = 26.337 (9) Å	θ = 3.1–26.0°
b = 28.349 (10) Å	µ = 0.08 mm−1
c = 4.990 (2) Å	T = 293 K
V = 3726 (2) Å3	Orthorhombic, colourless
Z = 8	0.35 × 0.25 × 0.20 mm

Bruker SMART APEXII area-detector diffractometer	1022 independent reflections
Radiation source: fine-focus sealed tube	886 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.035
ω and φ scans	θmax = 26.0°, θmin = 3.1°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −32→32
Tmin = 0.972, Tmax = 0.984	k = −31→34
4329 measured reflections	l = −6→4

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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.114	H-atom parameters constrained
S = 1.06	w = 1/[σ2(Fo2) + (0.0561P)2 + 2.1412P] where P = (Fo2 + 2Fc2)/3
1022 reflections	(Δ/σ)max < 0.001
114 parameters	Δρmax = 0.17 e Å−3
1 restraint	Δρmin = −0.13 e Å−3

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.

	x	y	z	Uiso*/Ueq	Occ. (<1)
O1	0.15629 (6)	0.10388 (6)	0.7445 (5)	0.0632 (5)
C4	0.25293 (9)	0.18516 (9)	0.9981 (6)	0.0580 (6)
H4	0.2873	0.1919	0.9767	0.070*
C2	0.18085 (8)	0.13881 (8)	0.8776 (6)	0.0499 (6)
C7	0.2500	0.2500	1.3451 (9)	0.0711 (11)
H7A	0.2245	0.2642	1.4598	0.085*	0.50
H7B	0.2755	0.2358	1.4598	0.085*	0.50
C1	0.15181 (8)	0.16511 (8)	1.0577 (6)	0.0552 (7)
C3	0.23209 (8)	0.14955 (8)	0.8487 (6)	0.0572 (7)
H3	0.2521	0.1326	0.7288	0.069*
C5	0.22521 (9)	0.21160 (8)	1.1795 (5)	0.0546 (6)
C6	0.17461 (9)	0.20091 (8)	1.2046 (6)	0.0578 (7)
H6	0.1549	0.2182	1.3240	0.069*
C9	0.18476 (10)	0.06998 (9)	0.5895 (6)	0.0621 (7)
H9	0.2076	0.0865	0.4661	0.075*
O2	0.07084 (7)	0.17443 (8)	1.2544 (9)	0.1226 (13)
C10	0.21526 (11)	0.03853 (10)	0.7716 (8)	0.0760 (9)
H10A	0.2397	0.0571	0.8674	0.114*
H10B	0.2325	0.0151	0.6667	0.114*
H10C	0.1930	0.0233	0.8968	0.114*
C11	0.14556 (13)	0.04302 (12)	0.4324 (8)	0.0882 (11)
H11A	0.1274	0.0643	0.3176	0.132*
H11B	0.1222	0.0281	0.5537	0.132*
H11C	0.1620	0.0194	0.3255	0.132*
C8	0.09748 (9)	0.15523 (10)	1.0940 (10)	0.0888 (13)
H8	0.0828	0.1325	0.9845	0.107*

	U11	U22	U33	U12	U13	U23
O1	0.0503 (9)	0.0492 (9)	0.0902 (13)	−0.0024 (7)	0.0055 (10)	−0.0102 (10)
C4	0.0436 (11)	0.0618 (14)	0.0686 (15)	−0.0084 (10)	0.0086 (12)	0.0086 (14)
C2	0.0445 (11)	0.0388 (11)	0.0663 (15)	0.0025 (9)	0.0052 (12)	0.0066 (11)
C7	0.079 (2)	0.074 (3)	0.060 (2)	−0.0213 (19)	0.000	0.000
C1	0.0430 (11)	0.0383 (11)	0.0844 (19)	0.0028 (9)	0.0120 (13)	0.0036 (13)
C3	0.0477 (12)	0.0544 (14)	0.0695 (16)	−0.0004 (10)	0.0158 (12)	−0.0006 (14)
C5	0.0576 (12)	0.0495 (13)	0.0568 (15)	−0.0065 (10)	0.0027 (12)	0.0081 (12)
C6	0.0560 (12)	0.0444 (12)	0.0730 (18)	0.0018 (10)	0.0181 (13)	0.0005 (14)
C9	0.0704 (15)	0.0549 (14)	0.0609 (15)	−0.0082 (12)	0.0218 (14)	−0.0046 (13)
O2	0.0639 (12)	0.0834 (15)	0.221 (4)	−0.0002 (10)	0.0623 (19)	−0.031 (2)
C10	0.0793 (17)	0.0574 (15)	0.091 (2)	0.0121 (13)	0.0235 (18)	−0.0004 (17)
C11	0.098 (2)	0.082 (2)	0.084 (2)	−0.0235 (17)	0.011 (2)	−0.016 (2)
C8	0.0464 (13)	0.0554 (15)	0.164 (4)	0.0008 (12)	0.024 (2)	−0.018 (2)

O1—C2	1.357 (3)	C5—C6	1.372 (3)
O1—C9	1.444 (3)	C6—H6	0.9300
C4—C3	1.370 (4)	C9—C10	1.505 (4)
C4—C5	1.384 (4)	C9—C11	1.505 (4)
C4—H4	0.9300	C9—H9	0.9800
C2—C3	1.391 (3)	O2—C8	1.196 (5)
C2—C1	1.396 (3)	C10—H10A	0.9600
C7—C5i	1.514 (4)	C10—H10B	0.9600
C7—C5	1.515 (4)	C10—H10C	0.9600
C7—H7A	0.9700	C11—H11A	0.9600
C7—H7B	0.9700	C11—H11B	0.9600
C1—C6	1.389 (3)	C11—H11C	0.9600
C1—C8	1.469 (3)	C8—H8	0.9300
C3—H3	0.9300
C2—O1—C9	120.03 (18)	C5—C6—H6	118.9
C3—C4—C5	122.9 (2)	C1—C6—H6	118.9
C3—C4—H4	118.5	O1—C9—C10	110.4 (3)
C5—C4—H4	118.5	O1—C9—C11	105.1 (2)
O1—C2—C3	124.9 (2)	C10—C9—C11	112.3 (2)
O1—C2—C1	116.35 (18)	O1—C9—H9	109.6
C3—C2—C1	118.8 (2)	C10—C9—H9	109.6
C5i—C7—C5	113.9 (4)	C11—C9—H9	109.6
C5i—C7—H7A	108.8	C9—C10—H10A	109.5
C5—C7—H7A	108.8	C9—C10—H10B	109.5
C5i—C7—H7B	108.8	H10A—C10—H10B	109.5
C5—C7—H7B	108.8	C9—C10—H10C	109.5
H7A—C7—H7B	107.7	H10A—C10—H10C	109.5
C6—C1—C2	119.6 (2)	H10B—C10—H10C	109.5
C6—C1—C8	119.7 (3)	C9—C11—H11A	109.5
C2—C1—C8	120.8 (2)	C9—C11—H11B	109.5
C4—C3—C2	119.6 (2)	H11A—C11—H11B	109.5
C4—C3—H3	120.2	C9—C11—H11C	109.5
C2—C3—H3	120.2	H11A—C11—H11C	109.5
C6—C5—C4	116.9 (2)	H11B—C11—H11C	109.5
C6—C5—C7	121.8 (2)	O2—C8—C1	124.6 (3)
C4—C5—C7	121.2 (2)	O2—C8—H8	117.7
C5—C6—C1	122.2 (2)	C1—C8—H8	117.7
C9—O1—C2—C3	9.8 (4)	C5i—C7—C5—C6	−122.2 (3)
C9—O1—C2—C1	−169.6 (2)	C5i—C7—C5—C4	58.8 (2)
O1—C2—C1—C6	178.9 (2)	C4—C5—C6—C1	0.4 (4)
C3—C2—C1—C6	−0.5 (4)	C7—C5—C6—C1	−178.6 (3)
O1—C2—C1—C8	−0.9 (4)	C2—C1—C6—C5	0.0 (4)
C3—C2—C1—C8	179.7 (3)	C8—C1—C6—C5	179.8 (3)
C5—C4—C3—C2	−0.1 (4)	C2—O1—C9—C10	68.9 (3)
O1—C2—C3—C4	−178.8 (2)	C2—O1—C9—C11	−169.7 (2)
C1—C2—C3—C4	0.6 (4)	C6—C1—C8—O2	−4.1 (6)
C3—C4—C5—C6	−0.4 (4)	C2—C1—C8—O2	175.7 (4)
C3—C4—C5—C7	178.7 (3)

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8···O1	0.93	2.42	2.749 (3)	101