Absolute configuration of (2S)-4-(4-hy­droxy­phen­yl)butan-2-ol

Yousuf, S.; Musharraf, S.G.; Khan, I.; Samiullah; Fun, H.-K.

doi:10.1107/S1600536811010026

organic compounds

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Volume 67| Part 4| April 2011| Page o952

doi:10.1107/S1600536811010026

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Absolute configuration of (2S)-4-(4-hydroxyphenyl)butan-2-ol

S. Yousuf,^a S. G. Musharraf,^a I. Khan,^b Samiullah ^b and Hoong-Kun Fun ^c ^*‡

^aH.E.J. Research Institute of Chemistry, International Center for Chemical and Biological Sciences, University of Karachi 75270, Pakistan, ^bDepartment of Pharmacy, University of Peshawar, Peshawar 25120, Pakistan, and ^cX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
^*Correspondence e-mail: hkfun@usm.my

(Received 14 March 2011; accepted 17 March 2011; online 23 March 2011)

The title compound, C₁₀H₁₄O₂, was isolated from the chloroform extract of Taxus wallichiana Zucc. In the crystal, molecules are linked by intermolecular O—H⋯O hydrogen bonds, forming sheets parallel to (100). There are weak intermolecular C—H⋯π interactions between the sheets.

Related literature

For the isolation of the title compound, see: Fan et al. (1999 ). For the biological activity and medicinal uses of Taxus. wallichiana Zucc, see: Ahmed (1997 ); Baquar (1995 ); Kaul (1997 ); Nisar et al. (2008a ,b ; 2010 ); Prasain et al. (2001 ); Wani et al. (1971 ).

Experimental

Crystal data

C₁₀H₁₄O₂
M_r = 166.21
Monoclinic, P 2₁
a = 7.2342 (2) Å
b = 6.3815 (2) Å
c = 9.9419 (4) Å
β = 92.216 (2)°
V = 458.63 (3) Å³
Z = 2
Cu Kα radiation
μ = 0.66 mm⁻¹
T = 100 K
0.39 × 0.12 × 0.05 mm

Data collection

Bruker SMART APEXII DUO CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.784, T_max = 0.966
4954 measured reflections
1455 independent reflections
1446 reflections with I > 2σ(I)
R_int = 0.028

Refinement

R[F² > 2σ(F²)] = 0.029
wR(F²) = 0.075
S = 1.08
1455 reflections
165 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.24 e Å⁻³
Absolute structure: Flack (1983 ), 579 Friedel pairs
Flack parameter: −0.03 (17)

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C1–C6 ring

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1O1⋯O2ⁱ	0.92 (2)	1.72 (2)	2.6247 (13)	166 (2)
O2—H1O2⋯O1ⁱⁱ	0.91 (2)	1.88 (2)	2.7869 (13)	177.8 (19)
C8—H8A⋯Cg1ⁱⁱⁱ	0.93 (2)	2.822 (15)	3.7033 (13)	158.1 (14)
Symmetry codes: (i) x, y, z-1; (ii) $[-x+1, y+{\script{1\over 2}}, -z+1]$ ; (iii) $[-x, y+{\script{3\over 2}}, -z+1]$ .

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXTL and PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811010026/lh5221sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811010026/lh5221Isup2.hkl

checkCIF report

Comment top

The genus Taxus belonging to the family Taxaceae is well known for its anticancer agents, namely taxol and dosetaxel (Wani et al., 1971; Prasain et al., 2001; Nisar et al., 2008a,b;2010). Taxus. wallichiana Zucc. (Himalayan Yew) is a small to medium sized evergreen tree, native to the northern areas of the Pakistan. Literature survey revealed that this plant is used traditionally for the treatment of high fever and acute painful conditions (Kaul, 1997). Leaves of the plant are used to make herbal tea for indigestion and epilepsy (Baquar, 1995; Ahmed, 1997). During our ongoing search on the medicinally important plants of Pakistan, the title compound was isolated from the chloroform-soluble part of Taxus. wallichiana and the structure was established on the basis of X-ray diffraction studies.

The molecular structure of the title compound is shown in Fig. 1. In the crystal structure, molecules are linked by intermolecular O1—H1O1···O2ⁱ and O2—H1O2···O1ⁱⁱ (see Table 1 for symmetry codes) hydrogen bonds to form two-dimensional sheets paralel to the (100) (Fig.2). A weak C—H···π interaction is also observed.

Related literature top

For the isolation of the title compound, see: Fan et al. (1999). For the biological activity and medicinal uses of Taxus. wallichiana Zucc, see: Ahmed (1997); Baquar (1995); Kaul (1997); Nisar et al. (2008a,b; 2010); Prasain et al. (2001); Wani et al. (1971).

Experimental top

Plant material: Taxus. wallichiana Zucc. was collected from the Hazara division of the North-western Frontier Province, Pakistan, in March 2005 and identified by Dr. Hasan Sher, a taxonomist of the Department of Botany, Jehanzeb Postgraduate College Saidu Sharif, Swat, Pakistan. A voucher specimen was deposited in the herbarium of the same institution. The aerial parts of the plant were air-dried under shade for six consecutive weeks at room temperature. The dried plant material was later on chopped, finely ground and stored in polyethylene bags under refrigeration for further experimentation.

The isolation of 4-(4'-hydroxyphenyl)-(2S)-butanol was previously carried out by Fan et al. (1999). Extraction and purification: The air-dried and powdered bark (4.0 K g) was macerated in methanol with occasional manual shaking at room temperature for a period of 72 h. The process was repeated 3 times followed by filtration. The combined filtrates were evaporated under reduced pressure at 313K to obtain a crude gummy material (514 g, 12.85% w/w), which was suspended in distilled water and successively extracted with hexane (11% w/w), chloroform (31.9% w/w), ethyl acetate (38.8% w/w), and finally with water (18.2% w/w) to give the respective fraction. The chloroform fraction (182 g) was further separated using silica gel column chromatography (95 mm in diameter). The column was eluted with increasing polarities of n-hexane with chloroform (1%-100%) followed by the gradient mixtures of chloroform and methanol. The methanol gradient was increased carefully to collect twenty seven sub-fractions (C1—C27). The sub-fraction C17 (611 mg) obtained on elution with 6% methanol/chloroform mixture was finally purified by flash column chromatography (silica gel, 8 g) by using chloroform: methanol; (95:5) as eluent to yield a colorless crystalline compound, 4-(4'-hydroxyphenyl)-(2S)-butanol (928 mg). Crystals suitable for X-ray diffraction were grown from a solution of the title compound in a mixture of chloroform: methanol (95:5).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids.
	Fig. 2. Part of the crystal structure with O-H···O hydrogen bonds shown as dashed lines. Only H atoms involved in hydrogen bonds are included.

(2S)-4-(4-hydroxyphenyl)butan-2-ol top

Crystal data top

C₁₀H₁₄O₂	F(000) = 180
M_r = 166.21	D_x = 1.204 Mg m⁻³
Monoclinic, P2₁	Cu Kα radiation, λ = 1.54178 Å
Hall symbol: P 2yb	Cell parameters from 3477 reflections
a = 7.2342 (2) Å	θ = 6.1–70.3°
b = 6.3815 (2) Å	µ = 0.66 mm⁻¹
c = 9.9419 (4) Å	T = 100 K
β = 92.216 (2)°	Block, colorles
V = 458.63 (3) Å³	0.39 × 0.12 × 0.05 mm
Z = 2

Data collection top

Bruker SMART APEXII DUO CCD area-detector diffractometer	1455 independent reflections
Radiation source: fine-focus sealed tube	1446 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.028
ϕ and ω scans	θ_max = 67.5°, θ_min = 6.1°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −8→8
T_min = 0.784, T_max = 0.966	k = −7→7
4954 measured reflections	l = −11→10

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.029	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.075	w = 1/[σ²(F_o²) + (0.0499P)² + 0.0461P] where P = (F_o² + 2F_c²)/3
S = 1.08	(Δ/σ)_max = 0.001
1455 reflections	Δρ_max = 0.19 e Å⁻³
165 parameters	Δρ_min = −0.24 e Å⁻³
1 restraint	Absolute structure: Flack (1983), 579 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.03 (17)

Crystal data top

C₁₀H₁₄O₂	V = 458.63 (3) Å³
M_r = 166.21	Z = 2
Monoclinic, P2₁	Cu Kα radiation
a = 7.2342 (2) Å	µ = 0.66 mm⁻¹
b = 6.3815 (2) Å	T = 100 K
c = 9.9419 (4) Å	0.39 × 0.12 × 0.05 mm
β = 92.216 (2)°

Data collection top

Bruker SMART APEXII DUO CCD area-detector diffractometer	1455 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	1446 reflections with I > 2σ(I)
T_min = 0.784, T_max = 0.966	R_int = 0.028
4954 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.029	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.075	Δρ_max = 0.19 e Å⁻³
S = 1.08	Δρ_min = −0.24 e Å⁻³
1455 reflections	Absolute structure: Flack (1983), 579 Friedel pairs
165 parameters	Absolute structure parameter: −0.03 (17)
1 restraint

Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K. Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105–107.

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	0.33418 (12)	0.03888 (15)	0.11761 (9)	0.0200 (2)
O2	0.33463 (12)	0.33901 (17)	0.93717 (9)	0.0214 (2)
C1	0.22229 (17)	0.3267 (2)	0.42530 (13)	0.0191 (3)
C2	0.25737 (17)	0.2886 (2)	0.29010 (14)	0.0184 (3)
C3	0.29911 (15)	0.08712 (19)	0.24875 (13)	0.0161 (3)
C4	0.30875 (17)	−0.0757 (2)	0.34234 (14)	0.0191 (3)
C5	0.27631 (16)	−0.0347 (2)	0.47664 (13)	0.0187 (3)
C6	0.23165 (16)	0.1659 (2)	0.52052 (13)	0.0173 (3)
C7	0.19572 (19)	0.2007 (2)	0.66828 (14)	0.0222 (3)
C8	0.20129 (16)	0.4288 (2)	0.71453 (13)	0.0179 (3)
C9	0.18659 (17)	0.4510 (2)	0.86638 (13)	0.0202 (3)
C10	0.1875 (2)	0.6786 (3)	0.91038 (16)	0.0286 (4)
H1	0.192 (2)	0.463 (3)	0.4534 (16)	0.019 (4)*
H2	0.245 (2)	0.401 (3)	0.2254 (19)	0.026 (4)*
H4	0.339 (2)	−0.216 (3)	0.3145 (17)	0.024 (4)*
H5	0.281 (2)	−0.143 (3)	0.5411 (18)	0.025 (4)*
H7A	0.076 (2)	0.136 (3)	0.6896 (18)	0.027 (4)*
H7B	0.293 (3)	0.123 (3)	0.720 (2)	0.032 (5)*
H8A	0.103 (3)	0.501 (3)	0.6728 (18)	0.026 (4)*
H8B	0.322 (2)	0.494 (3)	0.6865 (15)	0.013 (4)*
H9	0.078 (2)	0.383 (3)	0.8913 (17)	0.020 (4)*
H10A	0.075 (3)	0.755 (4)	0.873 (2)	0.044 (6)*
H10B	0.304 (2)	0.749 (3)	0.8792 (17)	0.021 (4)*
H10C	0.183 (3)	0.691 (3)	1.011 (2)	0.040 (5)*
H1O1	0.319 (3)	0.151 (4)	0.062 (2)	0.043 (6)*
H1O2	0.444 (3)	0.400 (3)	0.920 (2)	0.036 (5)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0240 (4)	0.0247 (5)	0.0115 (5)	0.0004 (4)	0.0046 (3)	−0.0002 (4)
O2	0.0213 (5)	0.0303 (5)	0.0125 (5)	−0.0034 (4)	0.0007 (3)	0.0033 (4)
C1	0.0245 (6)	0.0192 (7)	0.0135 (6)	−0.0005 (5)	0.0016 (5)	−0.0021 (5)
C2	0.0220 (6)	0.0222 (8)	0.0110 (6)	−0.0008 (5)	0.0003 (5)	0.0023 (5)
C3	0.0138 (6)	0.0244 (7)	0.0101 (6)	−0.0007 (5)	0.0023 (4)	−0.0021 (5)
C4	0.0188 (6)	0.0195 (7)	0.0193 (7)	0.0006 (5)	0.0038 (4)	0.0005 (5)
C5	0.0201 (6)	0.0218 (7)	0.0142 (7)	−0.0017 (5)	0.0018 (4)	0.0029 (5)
C6	0.0180 (6)	0.0223 (7)	0.0115 (7)	−0.0027 (5)	0.0003 (5)	0.0003 (5)
C7	0.0304 (7)	0.0262 (8)	0.0102 (7)	−0.0047 (6)	0.0024 (5)	−0.0003 (5)
C8	0.0172 (6)	0.0247 (7)	0.0119 (6)	−0.0009 (5)	0.0004 (4)	0.0005 (5)
C9	0.0161 (6)	0.0325 (8)	0.0123 (7)	−0.0010 (5)	0.0024 (4)	−0.0019 (6)
C10	0.0278 (7)	0.0378 (9)	0.0201 (8)	0.0062 (7)	−0.0012 (5)	−0.0108 (6)

Geometric parameters (Å, º) top

O1—C3	1.3728 (15)	C5—H5	0.94 (2)
O1—H1O1	0.91 (3)	C6—C7	1.5180 (17)
O2—C9	1.4473 (16)	C7—C8	1.5265 (19)
O2—H1O2	0.90 (2)	C7—H7A	0.988 (19)
C1—C6	1.3959 (19)	C7—H7B	0.99 (2)
C1—C2	1.3988 (18)	C8—C9	1.5241 (17)
C1—H1	0.943 (19)	C8—H8A	0.93 (2)
C2—C3	1.3865 (18)	C8—H8B	1.018 (15)
C2—H2	0.96 (2)	C9—C10	1.517 (2)
C3—C4	1.3948 (18)	C9—H9	0.938 (17)
C4—C5	1.390 (2)	C10—H10A	1.01 (2)
C4—H4	0.97 (2)	C10—H10B	1.013 (18)
C5—C6	1.3942 (19)	C10—H10C	1.01 (2)

C3—O1—H1O1	112.1 (15)	C8—C7—H7A	110.2 (11)
C9—O2—H1O2	109.6 (13)	C6—C7—H7B	106.5 (12)
C6—C1—C2	121.21 (12)	C8—C7—H7B	108.1 (12)
C6—C1—H1	118.9 (10)	H7A—C7—H7B	107.0 (15)
C2—C1—H1	119.9 (10)	C9—C8—C7	112.65 (11)
C3—C2—C1	119.72 (12)	C9—C8—H8A	108.3 (11)
C3—C2—H2	120.5 (11)	C7—C8—H8A	109.0 (12)
C1—C2—H2	119.7 (11)	C9—C8—H8B	109.0 (9)
O1—C3—C2	122.67 (11)	C7—C8—H8B	108.8 (9)
O1—C3—C4	117.40 (11)	H8A—C8—H8B	109.0 (14)
C2—C3—C4	119.93 (11)	O2—C9—C10	109.73 (11)
C5—C4—C3	119.64 (12)	O2—C9—C8	110.92 (10)
C5—C4—H4	119.9 (11)	C10—C9—C8	112.02 (12)
C3—C4—H4	120.4 (11)	O2—C9—H9	104.8 (11)
C4—C5—C6	121.57 (12)	C10—C9—H9	111.0 (11)
C4—C5—H5	120.8 (12)	C8—C9—H9	108.0 (10)
C6—C5—H5	117.6 (12)	C9—C10—H10A	111.3 (13)
C5—C6—C1	117.92 (12)	C9—C10—H10B	109.5 (11)
C5—C6—C7	119.18 (11)	H10A—C10—H10B	109.7 (16)
C1—C6—C7	122.90 (12)	C9—C10—H10C	111.3 (13)
C6—C7—C8	115.31 (11)	H10A—C10—H10C	105.7 (17)
C6—C7—H7A	109.3 (11)	H10B—C10—H10C	109.3 (15)

C6—C1—C2—C3	1.14 (18)	C2—C1—C6—C5	−0.29 (18)
C1—C2—C3—O1	179.72 (10)	C2—C1—C6—C7	179.64 (11)
C1—C2—C3—C4	−0.99 (17)	C5—C6—C7—C8	163.67 (11)
O1—C3—C4—C5	179.33 (10)	C1—C6—C7—C8	−16.26 (18)
C2—C3—C4—C5	0.01 (17)	C6—C7—C8—C9	−173.32 (10)
C3—C4—C5—C6	0.86 (17)	C7—C8—C9—O2	58.43 (14)
C4—C5—C6—C1	−0.71 (17)	C7—C8—C9—C10	−178.58 (11)
C4—C5—C6—C7	179.36 (11)

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C1–C6 ring

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1O1···O2ⁱ	0.92 (2)	1.72 (2)	2.6247 (13)	166 (2)
O2—H1O2···O1ⁱⁱ	0.91 (2)	1.88 (2)	2.7869 (13)	177.8 (19)
C8—H8A···Cg1ⁱⁱⁱ	0.93 (2)	2.822 (15)	3.7033 (13)	158.1 (14)

Symmetry codes: (i) x, y, z−1; (ii) −x+1, y+1/2, −z+1; (iii) −x, y+3/2, −z+1.

Experimental details

Crystal data
Chemical formula	C₁₀H₁₄O₂
M_r	166.21
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	100
a, b, c (Å)	7.2342 (2), 6.3815 (2), 9.9419 (4)
β (°)	92.216 (2)
V (Å³)	458.63 (3)
Z	2
Radiation type	Cu Kα
µ (mm⁻¹)	0.66
Crystal size (mm)	0.39 × 0.12 × 0.05

Data collection
Diffractometer	Bruker SMART APEXII DUO CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.784, 0.966
No. of measured, independent and observed [I > 2σ(I)] reflections	4954, 1455, 1446
R_int	0.028
(sin θ/λ)_max (Å⁻¹)	0.599

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.029, 0.075, 1.08
No. of reflections	1455
No. of parameters	165
No. of restraints	1
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.19, −0.24
Absolute structure	Flack (1983), 579 Friedel pairs
Absolute structure parameter	−0.03 (17)

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C1–C6 ring

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1O1···O2ⁱ	0.92 (2)	1.72 (2)	2.6247 (13)	166 (2)
O2—H1O2···O1ⁱⁱ	0.91 (2)	1.88 (2)	2.7869 (13)	177.8 (19)
C8—H8A···Cg1ⁱⁱⁱ	0.93 (2)	2.822 (15)	3.7033 (13)	158.1 (14)

Symmetry codes: (i) x, y, z−1; (ii) −x+1, y+1/2, −z+1; (iii) −x, y+3/2, −z+1.

Footnotes

‡Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

SY thanks the School of Physics, Universiti Sains Malaysia, for providing X-ray diffraction research facilities. HKF thanks the Malaysian Government and Universiti Sains Malaysia for the Research University Grant No. 1001/PFIZIK/811160.

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Volume 67| Part 4| April 2011| Page o952

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