3-[(3,5-Di-tert-butyl-2-hydroxy­benzyl­idene)methyl­eneamino]benzonitrile

Zhao, Y.-F.; Xiong, J.-P.; Zuo, Y.

doi:10.1107/S1600536809014809

organic compounds

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ISSN: 2056-9890

Volume 65| Part 5| May 2009| Page o1141

doi:10.1107/S1600536809014809

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3-[(3,5-Di-tert-butyl-2-hydroxybenzylidene)methyleneamino]benzonitrile

Yong-Feng Zhao,^a Jin-Ping Xiong ^a ^* and Yu Zuo ^a

^aCollege of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China
^*Correspondence e-mail: xiongjp@mail.buct.edu.cn

(Received 12 March 2009; accepted 21 April 2009; online 30 April 2009)

The molecule of the title compound, C₂₂H₂₆N₂O, displays a trans configuration with respect to the C=N double bond. The dihedral angle between the planes of the two aromatic rings is 26.30 (15)°. There is a strong intramolecular O—H⋯N hydrogen bond between the imine and hydroxyl groups.

Related literature

For general background on Schiff base coordination complexes, see: Weber et al. (2007 ); Chen et al. (2008 ); May et al. (2004 ). For double-bond-length data, see: Elmah et al. (1999 ).

Experimental

Crystal data

C₂₂H₂₆N₂O
M_r = 334.45
Monoclinic, P 2₁ /c
a = 14.897 (3) Å
b = 15.684 (3) Å
c = 8.8581 (18) Å
β = 97.86 (3)°
V = 2050.2 (7) Å³
Z = 4
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 293 K
0.2 × 0.2 × 0.2 mm

Data collection

Rigaku Mercury2 diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005 ) T_min = 0.903, T_max = 1.000 (expected range = 0.891–0.987)
10436 measured reflections
3701 independent reflections
1746 reflections with I > 2σ(I)
R_int = 0.079

Refinement

R[F² > 2σ(F²)] = 0.072
wR(F²) = 0.189
S = 0.99
3701 reflections
230 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.14 e Å⁻³
Δρ_min = −0.15 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1A⋯N2	1.03 (5)	1.68 (5)	2.612 (3)	149 (4)

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear; data reduction: CrystalClear; 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: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809014809/gw2063sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809014809/gw2063Isup2.hkl

checkCIF report

Comment top

Schiff base compounds have received considerable attention for many years, primarily due to their importance in the development of coordination chemistry related to magnetism (Weber, et al., 2007), catalysis (Chen, et al., 2008) and biological process (May, et al.,2004). Our group is interested in the synthesis and preparation of Schiff base. Here, we report the synthesis and crystal structure of the title compound, (I).

Fig. 1 shows ORTEP plots of the title compounds. The dihedral angle between the mean planes of the two aromatic rings is 26.30 (0.15) ° showing that the Schiff-base ligand adopts a non-planar conformation. As expected, the molecule displays a trans configuration about the central C8=N2 function bond. The C8=N2 bond length of 1.286 (3)Å indicates a high degree of double-bond character comparable with the corresponding bond lengths in other Schiff bases (1.280 (2) Å; Elmah et al., 1999). A strong intramolecular O–H···N hydrogen bond interaction is observed in the molecular structure.

Related literature top

For general background on Schiff base coordination complexes, see: Weber et al. (2007); Chen et al. (2008); May et al. (2004). For double-bond-length data, see: Elmah et al. (1999).

Experimental top

All chemicals were obtained from commercial sources and used without further purification. 3-aminobenzonitrile (0.59 g, 5 mmol) and 3,5-di-t-butyl-2-hydroxybenzaldehyde (1.05 g, 4.5 mmol)were dissolved in ethanol (20 ml). The mixture was heated to reflux for 7 h, then cooled to room temperature the solution was filtered and after two weeks yellow crystals suitable for X-ray diffraction study were obtained. Yield: 1.27 g, 85%.

Computing details top

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); 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: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. A view of the title compound with the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.

3-[(3,5-Di-tert-butyl-2-hydroxybenzylidene)methyleneamino]benzonitrile top

Crystal data top

C₂₂H₂₆N₂O	F(000) = 720
M_r = 334.45	D_x = 1.084 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 7104 reflections
a = 14.897 (3) Å	θ = 3.0–25.2°
b = 15.684 (3) Å	µ = 0.07 mm⁻¹
c = 8.8581 (18) Å	T = 293 K
β = 97.86 (3)°	Prism, colorless
V = 2050.2 (7) Å³	0.2 × 0.2 × 0.2 mm
Z = 4

Data collection top

Rigaku Mercury2 diffractometer	3701 independent reflections
Radiation source: fine-focus sealed tube	1746 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.079
Detector resolution: 13.6612 pixels mm^-1	θ_max = 25.2°, θ_min = 3.1°
ω scans	h = −17→17
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	k = −14→18
T_min = 0.903, T_max = 1.000	l = −9→10
10436 measured reflections

Refinement top

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)] = 0.072	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.189	H atoms treated by a mixture of independent and constrained refinement
S = 0.99	w = 1/[σ²(F_o²) + (0.0819P)²] where P = (F_o² + 2F_c²)/3
3701 reflections	(Δ/σ)_max = 0.004
230 parameters	Δρ_max = 0.14 e Å⁻³
0 restraints	Δρ_min = −0.15 e Å⁻³

Crystal data top

C₂₂H₂₆N₂O	V = 2050.2 (7) Å³
M_r = 334.45	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 14.897 (3) Å	µ = 0.07 mm⁻¹
b = 15.684 (3) Å	T = 293 K
c = 8.8581 (18) Å	0.2 × 0.2 × 0.2 mm
β = 97.86 (3)°

Data collection top

Rigaku Mercury2 diffractometer	3701 independent reflections
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	1746 reflections with I > 2σ(I)
T_min = 0.903, T_max = 1.000	R_int = 0.079
10436 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.072	0 restraints
wR(F²) = 0.189	H atoms treated by a mixture of independent and constrained refinement
S = 0.99	Δρ_max = 0.14 e Å⁻³
3701 reflections	Δρ_min = −0.15 e Å⁻³
230 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
O1	0.66011 (15)	0.15473 (13)	0.7833 (2)	0.0653 (6)
C10	0.72011 (19)	0.08905 (18)	0.8159 (3)	0.0505 (8)
N2	0.59185 (16)	0.11626 (15)	1.0309 (3)	0.0559 (7)
C11	0.78194 (18)	0.06970 (18)	0.7144 (3)	0.0492 (8)
C9	0.71779 (18)	0.04083 (18)	0.9488 (3)	0.0490 (7)
C14	0.77740 (19)	−0.02806 (19)	0.9807 (3)	0.0566 (8)
H14A	0.7755	−0.0593	1.0695	0.068*
C12	0.83890 (19)	0.00022 (19)	0.7535 (4)	0.0561 (8)
H12A	0.8803	−0.0134	0.6876	0.067*
C1	0.52589 (19)	0.1264 (2)	1.1329 (3)	0.0520 (8)
C8	0.6525 (2)	0.05759 (19)	1.0535 (3)	0.0534 (8)
H8A	0.6547	0.0243	1.1407	0.064*
C13	0.83925 (19)	−0.05108 (18)	0.8837 (4)	0.0545 (8)
C2	0.48863 (19)	0.20659 (19)	1.1417 (3)	0.0563 (8)
H2B	0.5078	0.2513	1.0850	0.068*
C3	0.4222 (2)	0.2205 (2)	1.2357 (4)	0.0610 (9)
C4	0.3933 (2)	0.1543 (3)	1.3211 (4)	0.0703 (10)
H4A	0.3489	0.1636	1.3834	0.084*
C6	0.49656 (19)	0.0600 (2)	1.2181 (4)	0.0608 (9)
H6A	0.5208	0.0057	1.2118	0.073*
C7	0.3820 (2)	0.3038 (3)	1.2386 (4)	0.0792 (11)
C5	0.4310 (2)	0.0748 (2)	1.3128 (4)	0.0710 (10)
H5A	0.4126	0.0304	1.3710	0.085*
C15	0.9008 (2)	−0.1292 (2)	0.9173 (4)	0.0705 (10)
C17	0.8421 (3)	−0.2099 (2)	0.9016 (6)	0.1168 (16)
H17A	0.8121	−0.2145	0.7989	0.175*
H17B	0.7977	−0.2068	0.9704	0.175*
H17C	0.8798	−0.2590	0.9257	0.175*
C16	0.9728 (3)	−0.1349 (3)	0.8100 (7)	0.145 (2)
H16A	0.9437	−0.1377	0.7065	0.217*
H16B	1.0088	−0.1851	0.8332	0.217*
H16C	1.0110	−0.0854	0.8229	0.217*
N1	0.3495 (3)	0.3705 (2)	1.2362 (5)	0.1135 (13)
C19	0.7872 (2)	0.1226 (2)	0.5690 (4)	0.0619 (9)
C20	0.6964 (2)	0.1167 (2)	0.4636 (4)	0.0807 (11)
H20A	0.6839	0.0581	0.4368	0.121*
H20B	0.6998	0.1493	0.3728	0.121*
H20C	0.6488	0.1388	0.5153	0.121*
C21	0.8071 (2)	0.2170 (2)	0.6111 (4)	0.0871 (12)
H21A	0.7609	0.2386	0.6665	0.131*
H21B	0.8079	0.2497	0.5198	0.131*
H21C	0.8650	0.2212	0.6733	0.131*
C18	0.9497 (3)	−0.1256 (2)	1.0812 (5)	0.1196 (17)
H18A	0.9058	−0.1221	1.1508	0.179*
H18B	0.9882	−0.0763	1.0931	0.179*
H18C	0.9857	−0.1761	1.1021	0.179*
C22	0.8623 (3)	0.0909 (3)	0.4806 (5)	0.1176 (17)
H22A	0.8515	0.0322	0.4529	0.176*
H22B	0.9199	0.0960	0.5434	0.176*
H22C	0.8625	0.1245	0.3901	0.176*
H1A	0.618 (3)	0.155 (3)	0.865 (6)	0.166 (19)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0747 (15)	0.0676 (14)	0.0544 (15)	0.0222 (12)	0.0120 (12)	0.0117 (12)
C10	0.0533 (18)	0.0542 (18)	0.0421 (19)	0.0053 (16)	0.0001 (15)	−0.0018 (15)
N2	0.0599 (16)	0.0620 (16)	0.0468 (17)	0.0058 (14)	0.0115 (13)	−0.0027 (13)
C11	0.0463 (17)	0.0592 (19)	0.0423 (19)	−0.0004 (16)	0.0064 (14)	−0.0020 (15)
C9	0.0556 (18)	0.0545 (18)	0.0364 (18)	0.0040 (16)	0.0047 (14)	−0.0008 (15)
C14	0.064 (2)	0.0587 (19)	0.0467 (19)	−0.0012 (17)	0.0041 (16)	0.0110 (16)
C12	0.0492 (18)	0.065 (2)	0.056 (2)	−0.0056 (16)	0.0124 (15)	−0.0055 (17)
C1	0.0488 (17)	0.064 (2)	0.0428 (19)	−0.0021 (17)	0.0063 (15)	−0.0084 (16)
C8	0.062 (2)	0.0577 (19)	0.0395 (18)	−0.0017 (17)	0.0056 (15)	−0.0024 (15)
C13	0.0469 (17)	0.0579 (19)	0.058 (2)	0.0023 (16)	0.0054 (15)	−0.0025 (17)
C2	0.058 (2)	0.060 (2)	0.052 (2)	−0.0047 (17)	0.0137 (16)	−0.0084 (16)
C3	0.058 (2)	0.068 (2)	0.058 (2)	−0.0018 (18)	0.0112 (17)	−0.0182 (19)
C4	0.055 (2)	0.095 (3)	0.065 (2)	−0.011 (2)	0.0217 (18)	−0.013 (2)
C6	0.057 (2)	0.063 (2)	0.062 (2)	−0.0070 (17)	0.0070 (17)	−0.0004 (18)
C7	0.081 (3)	0.077 (3)	0.085 (3)	−0.002 (2)	0.028 (2)	−0.023 (2)
C5	0.064 (2)	0.083 (3)	0.069 (2)	−0.013 (2)	0.0186 (19)	0.003 (2)
C15	0.059 (2)	0.065 (2)	0.085 (3)	0.0121 (18)	0.0026 (19)	0.0019 (19)
C17	0.108 (3)	0.067 (3)	0.166 (5)	0.005 (2)	−0.015 (3)	−0.008 (3)
C16	0.131 (4)	0.136 (4)	0.184 (5)	0.076 (3)	0.080 (4)	0.044 (4)
N1	0.120 (3)	0.088 (2)	0.140 (4)	0.008 (2)	0.046 (3)	−0.034 (2)
C19	0.061 (2)	0.075 (2)	0.051 (2)	−0.0047 (18)	0.0139 (17)	0.0107 (18)
C20	0.085 (2)	0.105 (3)	0.049 (2)	−0.011 (2)	−0.0005 (19)	0.007 (2)
C21	0.093 (3)	0.095 (3)	0.070 (3)	−0.032 (2)	−0.001 (2)	0.023 (2)
C18	0.105 (3)	0.099 (3)	0.138 (4)	0.030 (3)	−0.043 (3)	0.012 (3)
C22	0.115 (3)	0.160 (4)	0.090 (3)	0.033 (3)	0.061 (3)	0.045 (3)

Geometric parameters (Å, º) top

O1—C10	1.369 (3)	C7—N1	1.152 (4)
O1—H1A	1.03 (5)	C5—H5A	0.9300
C10—C9	1.404 (4)	C15—C17	1.535 (4)
C10—C11	1.405 (4)	C15—C16	1.530 (5)
N2—C8	1.286 (3)	C15—C18	1.533 (5)
N2—C1	1.431 (3)	C17—H17A	0.9600
C11—C12	1.395 (4)	C17—H17B	0.9600
C11—C19	1.543 (4)	C17—H17C	0.9600
C9—C14	1.403 (4)	C16—H16A	0.9600
C9—C8	1.456 (4)	C16—H16B	0.9600
C14—C13	1.391 (4)	C16—H16C	0.9600
C14—H14A	0.9300	C19—C22	1.534 (4)
C12—C13	1.406 (4)	C19—C20	1.537 (4)
C12—H12A	0.9300	C19—C21	1.545 (4)
C1—C2	1.382 (4)	C20—H20A	0.9600
C1—C6	1.391 (4)	C20—H20B	0.9600
C8—H8A	0.9300	C20—H20C	0.9600
C13—C15	1.534 (4)	C21—H21A	0.9600
C2—C3	1.396 (4)	C21—H21B	0.9600
C2—H2B	0.9300	C21—H21C	0.9600
C3—C4	1.387 (4)	C18—H18A	0.9600
C3—C7	1.438 (5)	C18—H18B	0.9600
C4—C5	1.374 (4)	C18—H18C	0.9600
C4—H4A	0.9300	C22—H22A	0.9600
C6—C5	1.390 (4)	C22—H22B	0.9600
C6—H6A	0.9300	C22—H22C	0.9600

C10—O1—H1A	108 (3)	C17—C15—C13	108.9 (3)
O1—C10—C9	119.5 (3)	C16—C15—C13	112.2 (3)
O1—C10—C11	119.6 (3)	C18—C15—C13	110.4 (3)
C9—C10—C11	120.9 (3)	C15—C17—H17A	109.5
C8—N2—C1	120.6 (3)	C15—C17—H17B	109.5
C12—C11—C10	116.1 (3)	H17A—C17—H17B	109.5
C12—C11—C19	121.9 (3)	C15—C17—H17C	109.5
C10—C11—C19	122.0 (3)	H17A—C17—H17C	109.5
C10—C9—C14	119.8 (3)	H17B—C17—H17C	109.5
C10—C9—C8	122.1 (3)	C15—C16—H16A	109.5
C14—C9—C8	118.1 (3)	C15—C16—H16B	109.5
C13—C14—C9	122.0 (3)	H16A—C16—H16B	109.5
C13—C14—H14A	119.0	C15—C16—H16C	109.5
C9—C14—H14A	119.0	H16A—C16—H16C	109.5
C11—C12—C13	125.8 (3)	H16B—C16—H16C	109.5
C11—C12—H12A	117.1	C22—C19—C20	108.2 (3)
C13—C12—H12A	117.1	C22—C19—C21	107.7 (3)
C2—C1—C6	119.5 (3)	C20—C19—C21	109.2 (3)
C2—C1—N2	116.9 (3)	C22—C19—C11	112.0 (3)
C6—C1—N2	123.6 (3)	C20—C19—C11	109.5 (2)
N2—C8—C9	123.1 (3)	C21—C19—C11	110.1 (3)
N2—C8—H8A	118.4	C19—C20—H20A	109.5
C9—C8—H8A	118.4	C19—C20—H20B	109.5
C14—C13—C12	115.5 (3)	H20A—C20—H20B	109.5
C14—C13—C15	121.1 (3)	C19—C20—H20C	109.5
C12—C13—C15	123.4 (3)	H20A—C20—H20C	109.5
C1—C2—C3	119.9 (3)	H20B—C20—H20C	109.5
C1—C2—H2B	120.0	C19—C21—H21A	109.5
C3—C2—H2B	120.0	C19—C21—H21B	109.5
C4—C3—C2	120.4 (3)	H21A—C21—H21B	109.5
C4—C3—C7	120.7 (3)	C19—C21—H21C	109.5
C2—C3—C7	118.9 (3)	H21A—C21—H21C	109.5
C5—C4—C3	119.4 (3)	H21B—C21—H21C	109.5
C5—C4—H4A	120.3	C15—C18—H18A	109.5
C3—C4—H4A	120.3	C15—C18—H18B	109.5
C5—C6—C1	120.1 (3)	H18A—C18—H18B	109.5
C5—C6—H6A	119.9	C15—C18—H18C	109.5
C1—C6—H6A	119.9	H18A—C18—H18C	109.5
N1—C7—C3	178.0 (4)	H18B—C18—H18C	109.5
C4—C5—C6	120.6 (3)	C19—C22—H22A	109.5
C4—C5—H5A	119.7	C19—C22—H22B	109.5
C6—C5—H5A	119.7	H22A—C22—H22B	109.5
C17—C15—C16	109.5 (3)	C19—C22—H22C	109.5
C17—C15—C18	107.9 (3)	H22A—C22—H22C	109.5
C16—C15—C18	107.9 (3)	H22B—C22—H22C	109.5

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···N2	1.03 (5)	1.68 (5)	2.612 (3)	149 (4)

Experimental details

Crystal data
Chemical formula	C₂₂H₂₆N₂O
M_r	334.45
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	14.897 (3), 15.684 (3), 8.8581 (18)
β (°)	97.86 (3)
V (Å³)	2050.2 (7)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.07
Crystal size (mm)	0.2 × 0.2 × 0.2

Data collection
Diffractometer	Rigaku Mercury2 diffractometer
Absorption correction	Multi-scan (CrystalClear; Rigaku, 2005)
T_min, T_max	0.903, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	10436, 3701, 1746
R_int	0.079
(sin θ/λ)_max (Å⁻¹)	0.600

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.072, 0.189, 0.99
No. of reflections	3701
No. of parameters	230
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.14, −0.15

Computer programs: CrystalClear (Rigaku, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···N2	1.03 (5)	1.68 (5)	2.612 (3)	149 (4)

References

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Volume 65| Part 5| May 2009| Page o1141

doi:10.1107/S1600536809014809

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