supplementary materials
2,3,5-Trimethyl-1,4-hydroquinone
The molecule of the title compound, C9H12O2, is approximately planar (mean atomic deviation = 0.0346 Å) and disposed about a crystallographic centre of symmetry. The H atom of the benzene ring is disordered over four orientations, with occupancies of 0.100 (3) and 0.401 (3) at the C atoms in the 2- and 3-positions and the same at their symmetric location. The H atoms of methyl group at the 2-position are disordered over two positions of equal occupancy. In the crystal structure, adjacent molecules are linked through O-H
O hydrogen bonds, forming a two-dimensional network.
A sample of commercial 2,3,5-trimethyl-1,4-hydroquinone(Aldrich) was crystalized
by slow evaporation of a solution in benzene: colourless platelet-shaped
crystals were formed after several days. 1H-NMR (400 MHz; CDCl3) δ: 2.145,
2.172, 2.181 (s, 9H, 3×CH3), 4.194, 4.213 (s, 2H, 2×OH), 6.453
(s,
1H, Ph—H); 13C-NMR(400 MHz; CDCl3) δ: 11.94,
12.28, 15.90(3×CH3), 114.33 (Ph-H), 120.82, 121.02,
123.48 (3×Ph-CH3), 145.90, 146.94 (2×Ph-OH).
The H atom of the benzene ring is disordered over four positions, the
occupancies are 0.100 (3),0.401 (3) and the same of their symmetric location. In
the case of methyl group(C4), H atoms are disordered over two sites of equal
occupancy by rotation about the C—C bonds. The hydroxyl hydrogen was located
by difference Fourier synthesis. Other H atoms were placed in geometry
calculated positions, taking full account of the disordered noted above, with
C—H set to 0.95 Å and 0.98 Å for benzene and methyl H atoms
respectively, and refined with a riding model, with Uiso(H) =
1.2Ueq(C) in all cases.
Data collection: RAPID-AUTO (Rigaku, 2004); cell refinement: RAPID-AUTO (Rigaku, 2004); data reduction: RAPID-AUTO (Rigaku, 2004); 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: SHELXTL (Sheldrick, 2008).
2,3,5-Trimethyl-1,4-hydroquinone
top
Crystal data top
| C9H12O2 | F(000) = 164 |
| Mr = 152.19 | Dx = 1.277 Mg m−3 |
| Monoclinic, P21/n | Melting point: 442(2) K |
| Hall symbol: -P 2yn | Mo Kα radiation, λ = 0.71073 Å |
| a = 8.035 (4) Å | Cell parameters from 930 reflections |
| b = 4.696 (2) Å | θ = 3.1–27.5° |
| c = 10.503 (5) Å | µ = 0.09 mm−1 |
| β = 92.813 (5)° | T = 93 K |
| V = 395.8 (3) Å3 | Platelet, colorless |
| Z = 2 | 0.50 × 0.23 × 0.05 mm |
Data collection top
Rigaku SPIDER
diffractometer | 905 independent reflections |
| Radiation source: Rotating Anode | 667 reflections with I > 2σ(I) |
| graphite | Rint = 0.031 |
| ω scans | θmax = 27.5°, θmin = 3.1° |
Absorption correction: ψ scan
(North et al., 1968) | h = −10→10 |
| Tmin = 0.957, Tmax = 0.996 | k = −6→6 |
| 3724 measured reflections | l = −13→13 |
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)] = 0.040 | Hydrogen site location: inferred from neighbouring sites |
| wR(F2) = 0.081 | H atoms treated by a mixture of independent and constrained refinement |
| S = 1.00 | w = 1/[σ2(Fo2) + (0.0146P)2 + 0.186P]
where P = (Fo2 + 2Fc2)/3 |
| 905 reflections | (Δ/σ)max < 0.001 |
| 62 parameters | Δρmax = 0.17 e Å−3 |
| 1 restraint | Δρmin = −0.11 e Å−3 |
Crystal data top
| C9H12O2 | V = 395.8 (3) Å3 |
| Mr = 152.19 | Z = 2 |
| Monoclinic, P21/n | Mo Kα radiation |
| a = 8.035 (4) Å | µ = 0.09 mm−1 |
| b = 4.696 (2) Å | T = 93 K |
| c = 10.503 (5) Å | 0.50 × 0.23 × 0.05 mm |
| β = 92.813 (5)° | |
Data collection top
Rigaku SPIDER
diffractometer | 667 reflections with I > 2σ(I) |
Absorption correction: ψ scan
(North et al., 1968) | Rint = 0.031 |
| Tmin = 0.957, Tmax = 0.996 | θmax = 27.5° |
| 3724 measured reflections | Standard reflections: 0 |
| 905 independent reflections | |
Refinement top
| R[F2 > 2σ(F2)] = 0.040 | H atoms treated by a mixture of independent and constrained refinement |
| wR(F2) = 0.081 | Δρmax = 0.17 e Å−3 |
| S = 1.00 | Δρmin = −0.11 e Å−3 |
| 905 reflections | Absolute structure: ? |
| 62 parameters | Flack parameter: ? |
| 1 restraint | Rogers parameter: ? |
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 | Uiso*/Ueq | Occ. (<1) |
| O1 | 0.26338 (14) | 0.4290 (2) | 0.68009 (10) | 0.0409 (3) | |
| C1 | 0.38434 (19) | 0.4579 (3) | 0.58997 (12) | 0.0326 (3) | |
| C2 | 0.34638 (18) | 0.6452 (3) | 0.48939 (13) | 0.0326 (3) | |
| C3 | 0.46482 (19) | 0.6852 (3) | 0.39874 (12) | 0.0325 (3) | |
| H2' | 0.2427 | 0.7424 | 0.4831 | 0.039* | 0.100 (3) |
| H3' | 0.4422 | 0.8107 | 0.3291 | 0.039* | 0.401 (3) |
| C4 | 0.1823 (2) | 0.8010 (4) | 0.47751 (16) | 0.0414 (5) | 0.900 (3) |
| H4A | 0.1143 | 0.7487 | 0.5489 | 0.050* | 0.4501 (15) |
| H4B | 0.1233 | 0.7487 | 0.3970 | 0.050* | 0.4501 (15) |
| H4C | 0.2025 | 1.0068 | 0.4790 | 0.050* | 0.4501 (15) |
| H4D | 0.1791 | 0.9207 | 0.4010 | 0.050* | 0.4501 (15) |
| H4E | 0.1701 | 0.9207 | 0.5529 | 0.050* | 0.4501 (15) |
| H4F | 0.0909 | 0.6627 | 0.4709 | 0.050* | 0.4501 (15) |
| C5 | 0.4153 (3) | 0.8844 (5) | 0.2919 (2) | 0.0353 (7) | 0.599 (3) |
| H5A | 0.2957 | 0.8652 | 0.2707 | 0.042* | 0.599 (3) |
| H5B | 0.4779 | 0.8375 | 0.2169 | 0.042* | 0.599 (3) |
| H5C | 0.4400 | 1.0808 | 0.3182 | 0.042* | 0.599 (3) |
| H1O | 0.273 (2) | 0.263 (5) | 0.7202 (18) | 0.072 (7)* | |
Atomic displacement parameters (Å2) top| | U11 | U22 | U33 | U12 | U13 | U23 |
| O1 | 0.0545 (7) | 0.0301 (6) | 0.0389 (6) | 0.0038 (5) | 0.0109 (5) | 0.0004 (5) |
| C1 | 0.0468 (9) | 0.0222 (7) | 0.0290 (7) | −0.0009 (6) | 0.0030 (6) | −0.0044 (5) |
| C2 | 0.0429 (8) | 0.0217 (7) | 0.0326 (7) | 0.0022 (6) | −0.0034 (6) | −0.0049 (5) |
| C3 | 0.0493 (9) | 0.0201 (7) | 0.0276 (7) | 0.0017 (6) | −0.0033 (6) | −0.0012 (5) |
| C4 | 0.0475 (11) | 0.0346 (9) | 0.0417 (9) | 0.0054 (8) | −0.0014 (8) | 0.0013 (7) |
| C5 | 0.0434 (14) | 0.0308 (13) | 0.0314 (12) | −0.0034 (11) | −0.0004 (10) | 0.0051 (10) |
Geometric parameters (Å, °) top
| O1—C1 | 1.3961 (17) | C4—H4A | 0.9800 |
| O1—H1O | 0.89 (2) | C4—H4B | 0.9800 |
| C1—C3i | 1.386 (2) | C4—H4C | 0.9800 |
| C1—C2 | 1.3968 (19) | C4—H4D | 0.9800 |
| C2—C3 | 1.392 (2) | C4—H4E | 0.9800 |
| C2—C4 | 1.508 (2) | C4—H4F | 0.9800 |
| C2—H2' | 0.9498 | C5—H3' | 0.5575 |
| C3—C1i | 1.386 (2) | C5—H5A | 0.9800 |
| C3—C5 | 1.500 (3) | C5—H5B | 0.9800 |
| C3—H3' | 0.9500 | C5—H5C | 0.9800 |
| C4—H2' | 0.5584 | | |
| | | |
| C1—O1—H1O | 111.0 (12) | H4A—C4—H4C | 109.5 |
| C3i—C1—O1 | 122.01 (13) | H4B—C4—H4C | 109.5 |
| C3i—C1—C2 | 121.85 (13) | C2—C4—H4D | 109.5 |
| O1—C1—C2 | 116.13 (13) | H2'—C4—H4D | 110.8 |
| C3—C2—C1 | 118.12 (13) | H4A—C4—H4D | 141.1 |
| C3—C2—C4 | 120.17 (13) | H4B—C4—H4D | 56.3 |
| C1—C2—C4 | 121.72 (14) | H4C—C4—H4D | 56.3 |
| C3—C2—H2' | 121.0 | C2—C4—H4E | 109.5 |
| C1—C2—H2' | 120.9 | H2'—C4—H4E | 108.6 |
| C4—C2—H2' | 0.8 | H4A—C4—H4E | 56.3 |
| C1i—C3—C2 | 120.04 (12) | H4B—C4—H4E | 141.1 |
| C1i—C3—C5 | 124.41 (15) | H4C—C4—H4E | 56.3 |
| C2—C3—C5 | 115.54 (15) | H4D—C4—H4E | 109.5 |
| C1i—C3—H3' | 120.0 | C2—C4—H4F | 109.5 |
| C2—C3—H3' | 120.0 | H2'—C4—H4F | 109.0 |
| C5—C3—H3' | 4.5 | H4A—C4—H4F | 56.3 |
| C2—C4—H2' | 1.4 | H4B—C4—H4F | 56.3 |
| C2—C4—H4A | 109.5 | H4C—C4—H4F | 141.1 |
| H2'—C4—H4A | 108.1 | H4D—C4—H4F | 109.5 |
| C2—C4—H4B | 109.5 | H4E—C4—H4F | 109.5 |
| H2'—C4—H4B | 110.3 | C3—C5—H3' | 7.7 |
| H4A—C4—H4B | 109.5 | H3'—C5—H5A | 116.4 |
| C2—C4—H4C | 109.5 | H3'—C5—H5B | 103.1 |
| H2'—C4—H4C | 109.9 | H3'—C5—H5C | 108.7 |
| | | |
| C3i—C1—C2—C3 | 0.3 (2) | C1—C2—C3—C1i | −0.3 (2) |
| O1—C1—C2—C3 | 178.66 (12) | C4—C2—C3—C1i | 179.88 (13) |
| C3i—C1—C2—C4 | −179.88 (13) | C1—C2—C3—C5 | 178.88 (14) |
| O1—C1—C2—C4 | −1.48 (19) | C4—C2—C3—C5 | −1.0 (2) |
| Symmetry codes: (i) −x+1, −y+1, −z+1. |
Hydrogen-bond geometry (Å, °) top
| D—H···A | D—H | H···A | D···A | D—H···A |
| O1—H1O···O1ii | 0.89 (2) | 1.92 (2) | 2.7833 (14) | 164.9 (18) |
| Symmetry codes: (ii) −x+1/2, y−1/2, −z+3/2. |
Table 1
Hydrogen-bond geometry (Å, °) top
| D—H···A | D—H | H···A | D···A | D—H···A |
| O1—H1O···O1i | 0.89 (2) | 1.92 (2) | 2.7833 (14) | 164.9 (18) |
| Symmetry codes: (i) −x+1/2, y−1/2, −z+3/2. |
The authors acknowledge financial support from Jiangsu Institute of Nuclear
Medicine.
Close, R. E. & Oroshnik, W. (1977). US Patent No. 4055575
Mulhauser, M. & Chabardes, P. (1986). Eur. Patent No. 0177398
North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351–359.
Rigaku (2004). RAPID-AUTO. Rigaku Corporation, Tokyo, Japan.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.
Yao, X. F. & Han, H. (1999). Hunan Huagong, A29, 14–16.
![[Figure 1]](./hg2613fig1thm.gif)
![[Figure 2]](./hg2613fig2thm.gif)
The molecule of the title compound (Fig.1) is useful as an important intermediate for the preparation of vitamin E (Close et al., 1977; Mulhauser et al., 1986; Yao et al., 1999;). We report here the crystal structure of the title compound. The crystal data show that the molecule is approximately planar and and disposed about a crystallographic centre of symmetry. Two hydroxy groups are attached at C1 and C1a of the benzene ring. The only one hydrogen of the benzene ring can be found in other four positions. The occupancies of hydrogen atom(H2') and methyl group(C4) are 0.100 (3) and 0.900 (3) at C2 and the same of its symmetric location(C2a). And the occupancies of H3' and C5 are 0.401 (3) and 0.599 (3) at C3 and C3a. Also the H atoms of methyl group(C4) are disordered over two positions by rotation about its C—C δ bond with equal occupancies.In the crystal structure, adjacent molecules are linked through O—H···O hydrogen bonds to form a two-dimensional hydrogen-bonded network parallel to the [1 0 1] crystallographic plane (Tab 1 and Fig. 2).