organic compounds
4,4′,6,6′-Tetra-tert-butyl-2,2′-[butane-1,4-diylbis(nitrilomethanylylidene)]diphenol
aDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: khaledi@siswa.um.edu.my
The title compound, C34H52N2O2, is centrosymmetric, the mid-point of the central C—C bond being located on an inversion centre. Intramolecular O—H⋯N and weak C—H⋯O hydrogen bonds are observed, but no significant intermolecular interactions occur in the crystal structure.
Related literature
For structures of some metal complexes of the title Schiff base, see: Doyle et al. (2007); Keizer et al. (2002a,b).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2007); cell SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: SHELXL97 and publCIF (Westrip, 2010).
Supporting information
10.1107/S1600536811041614/xu5350sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536811041614/xu5350Isup2.hkl
3,5-Di-tert-butyl-2-hydroxybenzaldehyde (5.86 g, 25 mmol) was dissolved in methanol (50 ml) in a round-bottomed flask fitted with a reflux condenser. The solution was heated, followed by portionwise addition of 1,4-diaminobutane (1.10 g; 12.5 mmol). The pale yellow solution formed was then gently refluxed for 3 h. The product obtained on cooling was recrystallized from ethanol at room temperature to give X-ray quality crystals of the title compound.
The C-bound H atoms were placed at calculated positions and refined as riding on their parent atoms, with C–H = 0.95 (aryl), 0.98 (methyl) and 0.99 (methylene) Å. The O-bound H atom was located in a difference Fourier map and refined freely. For all H atoms Uiso(H) were set to 1.2–1.5Ueq(carrier atom).
Data collection: APEX2 (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and publCIF (Westrip, 2010).Fig. 1. Molecular structure of the title compound with displacement ellipsoids at the 50% probability level. Hydrogen atoms are drawn as spheres of arbitrary radius. |
C34H52N2O2 | F(000) = 572 |
Mr = 520.78 | Dx = 1.095 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 4857 reflections |
a = 19.1255 (4) Å | θ = 2.4–30.3° |
b = 9.5702 (2) Å | µ = 0.07 mm−1 |
c = 8.6312 (1) Å | T = 100 K |
β = 90.383 (1)° | Plate, yellow |
V = 1579.78 (5) Å3 | 0.26 × 0.15 × 0.06 mm |
Z = 2 |
Bruker APEXII CCD diffractometer | 3631 independent reflections |
Radiation source: fine-focus sealed tube | 3039 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.024 |
ϕ and ω scans | θmax = 27.5°, θmin = 2.1° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −24→24 |
Tmin = 0.983, Tmax = 0.996 | k = −12→12 |
14602 measured reflections | l = −11→11 |
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)] = 0.043 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.114 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0533P)2 + 0.5079P] where P = (Fo2 + 2Fc2)/3 |
3631 reflections | (Δ/σ)max < 0.001 |
181 parameters | Δρmax = 0.30 e Å−3 |
0 restraints | Δρmin = −0.16 e Å−3 |
C34H52N2O2 | V = 1579.78 (5) Å3 |
Mr = 520.78 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 19.1255 (4) Å | µ = 0.07 mm−1 |
b = 9.5702 (2) Å | T = 100 K |
c = 8.6312 (1) Å | 0.26 × 0.15 × 0.06 mm |
β = 90.383 (1)° |
Bruker APEXII CCD diffractometer | 3631 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 3039 reflections with I > 2σ(I) |
Tmin = 0.983, Tmax = 0.996 | Rint = 0.024 |
14602 measured reflections |
R[F2 > 2σ(F2)] = 0.043 | 0 restraints |
wR(F2) = 0.114 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.30 e Å−3 |
3631 reflections | Δρmin = −0.16 e Å−3 |
181 parameters |
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 | ||
O1 | 0.38365 (4) | 0.98230 (9) | 0.47339 (10) | 0.0267 (2) | |
H1 | 0.4145 (8) | 0.9488 (17) | 0.3998 (19) | 0.040* | |
N1 | 0.43079 (5) | 0.86964 (11) | 0.22286 (12) | 0.0276 (2) | |
C1 | 0.31824 (6) | 0.96886 (11) | 0.41401 (12) | 0.0198 (2) | |
C2 | 0.26044 (6) | 1.01998 (11) | 0.49629 (12) | 0.0193 (2) | |
C3 | 0.19476 (6) | 1.00283 (11) | 0.42796 (12) | 0.0203 (2) | |
H3 | 0.1553 | 1.0373 | 0.4824 | 0.024* | |
C4 | 0.18292 (6) | 0.93820 (12) | 0.28429 (12) | 0.0197 (2) | |
C5 | 0.24129 (6) | 0.88907 (11) | 0.20702 (12) | 0.0196 (2) | |
H5 | 0.2353 | 0.8443 | 0.1096 | 0.024* | |
C6 | 0.30834 (6) | 0.90361 (11) | 0.26843 (12) | 0.0194 (2) | |
C7 | 0.26927 (7) | 1.09122 (12) | 0.65518 (12) | 0.0230 (3) | |
C8 | 0.31935 (8) | 1.21639 (13) | 0.64423 (15) | 0.0348 (3) | |
H8A | 0.3004 | 1.2849 | 0.5707 | 0.052* | |
H8B | 0.3651 | 1.1842 | 0.6085 | 0.052* | |
H8C | 0.3244 | 1.2599 | 0.7465 | 0.052* | |
C9 | 0.29756 (7) | 0.98400 (12) | 0.77258 (13) | 0.0254 (3) | |
H9A | 0.3430 | 0.9492 | 0.7377 | 0.038* | |
H9B | 0.2647 | 0.9058 | 0.7807 | 0.038* | |
H9C | 0.3030 | 1.0286 | 0.8741 | 0.038* | |
C10 | 0.19963 (7) | 1.14567 (14) | 0.71697 (14) | 0.0323 (3) | |
H10A | 0.2074 | 1.1915 | 0.8172 | 0.049* | |
H10B | 0.1672 | 1.0674 | 0.7300 | 0.049* | |
H10C | 0.1797 | 1.2130 | 0.6434 | 0.049* | |
C11 | 0.10988 (6) | 0.92199 (13) | 0.21236 (13) | 0.0246 (3) | |
C12 | 0.09358 (7) | 0.76642 (15) | 0.19055 (17) | 0.0357 (3) | |
H12A | 0.0932 | 0.7200 | 0.2918 | 0.053* | |
H12B | 0.1294 | 0.7237 | 0.1252 | 0.053* | |
H12C | 0.0477 | 0.7560 | 0.1407 | 0.053* | |
C13 | 0.10838 (7) | 0.99276 (15) | 0.05301 (15) | 0.0339 (3) | |
H13A | 0.0630 | 0.9757 | 0.0029 | 0.051* | |
H13B | 0.1457 | 0.9542 | −0.0114 | 0.051* | |
H13C | 0.1154 | 1.0936 | 0.0656 | 0.051* | |
C14 | 0.05296 (7) | 0.9870 (2) | 0.31222 (17) | 0.0449 (4) | |
H14A | 0.0526 | 0.9413 | 0.4138 | 0.067* | |
H14B | 0.0074 | 0.9745 | 0.2615 | 0.067* | |
H14C | 0.0623 | 1.0870 | 0.3255 | 0.067* | |
C15 | 0.36766 (6) | 0.85464 (12) | 0.17746 (13) | 0.0225 (2) | |
H15 | 0.3589 | 0.8100 | 0.0810 | 0.027* | |
C16 | 0.48707 (6) | 0.82786 (14) | 0.11850 (16) | 0.0312 (3) | |
H16A | 0.4676 | 0.7714 | 0.0324 | 0.037* | |
H16B | 0.5214 | 0.7697 | 0.1755 | 0.037* | |
C17 | 0.52336 (6) | 0.95676 (14) | 0.05349 (15) | 0.0294 (3) | |
H17A | 0.5653 | 0.9268 | −0.0045 | 0.035* | |
H17B | 0.5393 | 1.0163 | 0.1407 | 0.035* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0244 (4) | 0.0311 (5) | 0.0246 (4) | −0.0036 (4) | −0.0030 (3) | −0.0032 (3) |
N1 | 0.0240 (5) | 0.0289 (6) | 0.0299 (5) | −0.0012 (4) | 0.0047 (4) | −0.0003 (4) |
C1 | 0.0244 (6) | 0.0152 (5) | 0.0196 (5) | −0.0026 (4) | −0.0019 (4) | 0.0027 (4) |
C2 | 0.0299 (6) | 0.0126 (5) | 0.0155 (5) | 0.0009 (4) | −0.0011 (4) | 0.0015 (4) |
C3 | 0.0273 (6) | 0.0173 (5) | 0.0163 (5) | 0.0051 (4) | 0.0019 (4) | 0.0010 (4) |
C4 | 0.0241 (6) | 0.0183 (5) | 0.0167 (5) | 0.0011 (4) | −0.0012 (4) | 0.0022 (4) |
C5 | 0.0271 (6) | 0.0169 (5) | 0.0149 (5) | −0.0014 (4) | 0.0005 (4) | −0.0011 (4) |
C6 | 0.0245 (6) | 0.0150 (5) | 0.0188 (5) | −0.0013 (4) | 0.0023 (4) | 0.0014 (4) |
C7 | 0.0365 (7) | 0.0163 (5) | 0.0163 (5) | 0.0007 (5) | −0.0025 (4) | −0.0011 (4) |
C8 | 0.0597 (9) | 0.0205 (6) | 0.0241 (6) | −0.0090 (6) | −0.0021 (6) | −0.0033 (5) |
C9 | 0.0379 (7) | 0.0204 (6) | 0.0178 (5) | 0.0002 (5) | −0.0058 (5) | −0.0004 (4) |
C10 | 0.0474 (8) | 0.0301 (7) | 0.0195 (5) | 0.0118 (6) | −0.0011 (5) | −0.0064 (5) |
C11 | 0.0242 (6) | 0.0301 (6) | 0.0194 (5) | 0.0025 (5) | −0.0021 (4) | −0.0005 (4) |
C12 | 0.0289 (7) | 0.0346 (7) | 0.0434 (8) | −0.0081 (6) | −0.0053 (6) | 0.0044 (6) |
C13 | 0.0378 (7) | 0.0374 (7) | 0.0263 (6) | −0.0042 (6) | −0.0118 (5) | 0.0057 (5) |
C14 | 0.0272 (7) | 0.0746 (12) | 0.0327 (7) | 0.0171 (7) | −0.0063 (6) | −0.0116 (7) |
C15 | 0.0276 (6) | 0.0184 (5) | 0.0215 (5) | −0.0020 (4) | 0.0035 (4) | −0.0001 (4) |
C16 | 0.0245 (6) | 0.0314 (7) | 0.0377 (7) | 0.0021 (5) | 0.0075 (5) | −0.0009 (5) |
C17 | 0.0192 (6) | 0.0355 (7) | 0.0334 (6) | −0.0014 (5) | 0.0037 (5) | −0.0032 (5) |
O1—C1 | 1.3549 (14) | C9—H9C | 0.9800 |
O1—H1 | 0.927 (16) | C10—H10A | 0.9800 |
N1—C15 | 1.2749 (15) | C10—H10B | 0.9800 |
N1—C16 | 1.4638 (15) | C10—H10C | 0.9800 |
C1—C2 | 1.4058 (16) | C11—C14 | 1.5257 (18) |
C1—C6 | 1.4147 (15) | C11—C12 | 1.5325 (18) |
C2—C3 | 1.3939 (16) | C11—C13 | 1.5332 (16) |
C2—C7 | 1.5398 (14) | C12—H12A | 0.9800 |
C3—C4 | 1.4028 (15) | C12—H12B | 0.9800 |
C3—H3 | 0.9500 | C12—H12C | 0.9800 |
C4—C5 | 1.3863 (15) | C13—H13A | 0.9800 |
C4—C11 | 1.5328 (16) | C13—H13B | 0.9800 |
C5—C6 | 1.3914 (16) | C13—H13C | 0.9800 |
C5—H5 | 0.9500 | C14—H14A | 0.9800 |
C6—C15 | 1.4613 (15) | C14—H14B | 0.9800 |
C7—C10 | 1.5295 (17) | C14—H14C | 0.9800 |
C7—C8 | 1.5371 (17) | C15—H15 | 0.9500 |
C7—C9 | 1.5380 (15) | C16—C17 | 1.5244 (18) |
C8—H8A | 0.9800 | C16—H16A | 0.9900 |
C8—H8B | 0.9800 | C16—H16B | 0.9900 |
C8—H8C | 0.9800 | C17—C17i | 1.525 (3) |
C9—H9A | 0.9800 | C17—H17A | 0.9900 |
C9—H9B | 0.9800 | C17—H17B | 0.9900 |
C1—O1—H1 | 107.4 (10) | H10A—C10—H10C | 109.5 |
C15—N1—C16 | 118.61 (11) | H10B—C10—H10C | 109.5 |
O1—C1—C2 | 120.20 (10) | C14—C11—C12 | 108.67 (12) |
O1—C1—C6 | 119.71 (10) | C14—C11—C4 | 112.44 (10) |
C2—C1—C6 | 120.09 (10) | C12—C11—C4 | 109.40 (10) |
C3—C2—C1 | 117.05 (10) | C14—C11—C13 | 108.51 (11) |
C3—C2—C7 | 121.48 (10) | C12—C11—C13 | 108.45 (10) |
C1—C2—C7 | 121.47 (10) | C4—C11—C13 | 109.28 (10) |
C2—C3—C4 | 124.44 (10) | C11—C12—H12A | 109.5 |
C2—C3—H3 | 117.8 | C11—C12—H12B | 109.5 |
C4—C3—H3 | 117.8 | H12A—C12—H12B | 109.5 |
C5—C4—C3 | 116.69 (10) | C11—C12—H12C | 109.5 |
C5—C4—C11 | 120.36 (10) | H12A—C12—H12C | 109.5 |
C3—C4—C11 | 122.95 (10) | H12B—C12—H12C | 109.5 |
C4—C5—C6 | 121.73 (10) | C11—C13—H13A | 109.5 |
C4—C5—H5 | 119.1 | C11—C13—H13B | 109.5 |
C6—C5—H5 | 119.1 | H13A—C13—H13B | 109.5 |
C5—C6—C1 | 120.00 (10) | C11—C13—H13C | 109.5 |
C5—C6—C15 | 118.70 (10) | H13A—C13—H13C | 109.5 |
C1—C6—C15 | 121.27 (10) | H13B—C13—H13C | 109.5 |
C10—C7—C8 | 107.48 (10) | C11—C14—H14A | 109.5 |
C10—C7—C9 | 107.51 (10) | C11—C14—H14B | 109.5 |
C8—C7—C9 | 110.11 (10) | H14A—C14—H14B | 109.5 |
C10—C7—C2 | 111.77 (10) | C11—C14—H14C | 109.5 |
C8—C7—C2 | 110.79 (9) | H14A—C14—H14C | 109.5 |
C9—C7—C2 | 109.11 (9) | H14B—C14—H14C | 109.5 |
C7—C8—H8A | 109.5 | N1—C15—C6 | 122.40 (10) |
C7—C8—H8B | 109.5 | N1—C15—H15 | 118.8 |
H8A—C8—H8B | 109.5 | C6—C15—H15 | 118.8 |
C7—C8—H8C | 109.5 | N1—C16—C17 | 110.12 (11) |
H8A—C8—H8C | 109.5 | N1—C16—H16A | 109.6 |
H8B—C8—H8C | 109.5 | C17—C16—H16A | 109.6 |
C7—C9—H9A | 109.5 | N1—C16—H16B | 109.6 |
C7—C9—H9B | 109.5 | C17—C16—H16B | 109.6 |
H9A—C9—H9B | 109.5 | H16A—C16—H16B | 108.1 |
C7—C9—H9C | 109.5 | C16—C17—C17i | 113.31 (13) |
H9A—C9—H9C | 109.5 | C16—C17—H17A | 108.9 |
H9B—C9—H9C | 109.5 | C17i—C17—H17A | 108.9 |
C7—C10—H10A | 109.5 | C16—C17—H17B | 108.9 |
C7—C10—H10B | 109.5 | C17i—C17—H17B | 108.9 |
H10A—C10—H10B | 109.5 | H17A—C17—H17B | 107.7 |
C7—C10—H10C | 109.5 |
Symmetry code: (i) −x+1, −y+2, −z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N1 | 0.927 (16) | 1.735 (17) | 2.5840 (13) | 150.8 (14) |
C8—H8B···O1 | 0.98 | 2.29 | 2.9546 (16) | 125 |
C9—H9A···O1 | 0.98 | 2.44 | 3.0720 (15) | 122 |
Experimental details
Crystal data | |
Chemical formula | C34H52N2O2 |
Mr | 520.78 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 100 |
a, b, c (Å) | 19.1255 (4), 9.5702 (2), 8.6312 (1) |
β (°) | 90.383 (1) |
V (Å3) | 1579.78 (5) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.07 |
Crystal size (mm) | 0.26 × 0.15 × 0.06 |
Data collection | |
Diffractometer | Bruker APEXII CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.983, 0.996 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 14602, 3631, 3039 |
Rint | 0.024 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.043, 0.114, 1.03 |
No. of reflections | 3631 |
No. of parameters | 181 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.30, −0.16 |
Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), X-SEED (Barbour, 2001), SHELXL97 (Sheldrick, 2008) and publCIF (Westrip, 2010).
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···N1 | 0.927 (16) | 1.735 (17) | 2.5840 (13) | 150.8 (14) |
C8—H8B···O1 | 0.98 | 2.29 | 2.9546 (16) | 124.6 |
C9—H9A···O1 | 0.98 | 2.44 | 3.0720 (15) | 122.2 |
Acknowledgements
Financial support from the University of Malaya is highly appreciated (PPP grant No. PS342/2009 C)
References
Barbour, L. J. (2001). J. Supramol. Chem. 1, 189–191. CrossRef CAS Google Scholar
Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Doyle, D. J., Gibson, V. C. & White, A. J. P. (2007). Dalton Trans. pp. 358–363. Web of Science CSD CrossRef Google Scholar
Keizer, T. S., De Pue, L. J., Parkin, S. & Atwood, D. A. (2002a). J. Cluster Sci. 13, 609–620. Web of Science CSD CrossRef CAS Google Scholar
Keizer, T. S., De Pue, L. J., Parkin, S. & Atwood, D. A. (2002b). J. Am. Chem. Soc. 124, 1864–1865. Web of Science CSD CrossRef PubMed CAS Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920–925. Web of Science CrossRef CAS IUCr Journals Google Scholar
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The title Schiff base has been displayed ambidentate ligation behavior towards metal ions (Doyle et al., 2007; Keizer et al., 2002a,b). Herein, wish to report the crystal structure of the free ligand, obtained through the condensation reaction of 3,5-di-tert-butyl-2-hydroxybenzaldehyde and 1,4-diaminobutane. The molecule lies across a crystallographic inversion centre. The imino group is almost coplanar with the phenyl ring [dihedral angle = 3.00 (13)] and adopts an E configuration. The hydroxyl group is engaged in an intramolecular O—H···N hydrogen bond with the imine group. Moreover, it acts as an acceptor in two intramolecular C—H···O hydrogen bonds (Table 1). The structure does not display any significant intermolecular interactions.