rac-(S)-2-(1H-Imidazol-1-yl)-3-methyl­butan-1-ol

Abstract

In the crystal structure of the title compound, C₈H₁₄N₂O, inter­molecular O—H⋯N hydrogen bonds link mol­ecules related by translation along the a axis into chains. Weak inter­molecular C—H⋯O hydrogen bonds and C—H⋯π inter­actions enhance the crystal packing stability.

Related literature

For useful applications of imidazole derivatives, see Lu et al. (2006 ▶); Zou et al. (2006 ▶). For details of the synthesis, see Bao et al. (2003 ▶); Guo et al. (2006 ▶).

Experimental

Crystal data

• C₈H₁₄N₂O

• M _r = 154.21

• Monoclinic,

• a = 7.356 (4) Å

• b = 7.212 (3) Å

• c = 16.549 (5) Å

• β = 90.54 (3)°

• V = 877.9 (7) ų

• Z = 4

• Mo Kα radiation

• μ = 0.08 mm⁻¹

• T = 292 K

• 0.58 × 0.54 × 0.42 mm

Data collection

• Enraf–Nonius CAD-4 diffractometer

• Absorption correction: none

• 1931 measured reflections

• 1630 independent reflections

• 965 reflections with I > 2σ(I)

• R _int = 0.004

• 3 standard reflections every 120 reflections intensity decay: 0.3%

Refinement

• R[F ² > 2σ(F ²)] = 0.067

• wR(F ²) = 0.197

• S = 1.18

• 1630 reflections

• 104 parameters

• H-atom parameters constrained

• Δρ_max = 0.31 e Å⁻³

• Δρ_min = −0.24 e Å⁻³

Data collection: DIFRAC (Gabe & White, 1993 ▶); cell refinement: DIFRAC; data reduction: NRCVAX (Gabe et al., 1989 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 ▶); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 ▶).

Supplementary Material

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

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N2i	0.82	1.93	2.751 (3)	176
C1—H1A⋯O1ii	0.93	2.43	3.353 (4)	173
C4—H4⋯Cgii	0.98	2.86	3.716 (4)	146

Symmetry codes: (i) ; (ii) . Cg is the centroid of the C1–C3/N1/N2 ring.

supplementary crystallographic information

Comment

Imidazole is important for biological systems, and its derivatives have attracted widespread interest due to their further expanded application in perfume chemistry and in the construction of some interesting metal–organic frameworks (Lu et al. 2006; Zou et al. 2006). Here, we report the crystal structure of the title compound, (I), which is a basic unit of constructing chiral receptors and could be applied for the preparation of perfume.

As shown in Fig. 1, there is a chiral center at C4 derived from the source L-valine. In the crystal, intermolecular O—H···N hydrogen bonds (Table 1) link the molecules related by translation along axis a into chains. Weak intermolecular C—H···O hydrogen bonds and C—H···π interactions (Table 1) enhance the crystal packing stability.

Experimental

The title compound was prepared according to the literature (Guo et al. 2006). Starting from L-valine, methyl 2-(1H-imidazol-1-yl)-3-methylbutanoate was easily prepared according to literature procedure (Bao et al. 2003). Following, NaBH₄ (1.52 g, 40 mmol) was added to methyl 2-(1H-imidazol-1-yl)-3-methylbutanoate (1.82 g, 10.0 mmol) in ethanol (50 ml) at 273 K during 30 min. The mixture was stirred at 333 K for another 20 h and then evaporated under vacuum. The residue was diluted with 50 ml saturated K₂CO₃ and extracted with 30 ml ethyl acetate. The organic layer was dried over anhydrous Na₂SO₄ and concentrated under reduced pressure. The resulting residue was purified by column chromatography on silica gel eluting with CH₂Cl₂/CH₃OH (20/1, v/v). Then, colourless crystals suitable for X-ray analysis can be obtained by recrystallization of the compound from ethyl acetate.

Refinement

All H atoms were positioned geometrically and refined in the riding model approximation, with C—H = 0.93–0.98 Å and O—H = 0.82 Å, and U_iso(H) = 1.2–1.5 U_eq of the parent atom.

Figures

Fig. 1.

The molecular structure of (I), showing 30% probability displacement ellipsoids and the atomic numbering.

Crystal data

C8H14N2O	F(000) = 336
Mr = 154.21	Dx = 1.167 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 21 reflections
a = 7.356 (4) Å	θ = 4.6–7.4°
b = 7.212 (3) Å	µ = 0.08 mm−1
c = 16.549 (5) Å	T = 292 K
β = 90.54 (3)°	Block, colourless
V = 877.9 (7) Å3	0.58 × 0.54 × 0.42 mm
Z = 4

Data collection

Enraf–Nonius CAD-4 diffractometer	Rint = 0.004
Radiation source: fine-focus sealed tube	θmax = 25.5°, θmin = 2.5°
graphite	h = −8→8
ω/2θ scans	k = 0→8
1931 measured reflections	l = −7→20
1630 independent reflections	3 standard reflections every 120 reflections
965 reflections with I > 2σ(I)	intensity decay: 0.3%

Refinement

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)] = 0.067	H-atom parameters constrained
wR(F2) = 0.197	w = 1/[σ2(Fo2) + (0.0941P)2] where P = (Fo2 + 2Fc2)/3
S = 1.18	(Δ/σ)max < 0.001
1630 reflections	Δρmax = 0.31 e Å−3
104 parameters	Δρmin = −0.24 e Å−3
0 restraints	Extinction correction: SHELXS97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.046 (11)

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.4065 (2)	0.1870 (3)	0.31165 (14)	0.0557 (7)
H1	0.3011	0.1697	0.3255	0.084*
N1	0.7629 (3)	0.0340 (3)	0.34211 (14)	0.0459 (7)
N2	1.0479 (3)	0.1263 (4)	0.34916 (16)	0.0598 (8)
C4	0.6043 (3)	−0.0816 (4)	0.32307 (17)	0.0456 (8)
H4	0.6473	−0.1848	0.2898	0.055*
C5	0.4713 (4)	0.0284 (4)	0.27157 (18)	0.0480 (8)
H5A	0.5306	0.0660	0.2221	0.058*
H5B	0.3692	−0.0503	0.2570	0.058*
C1	0.9353 (4)	0.0047 (4)	0.31778 (19)	0.0514 (8)
H1A	0.9698	−0.0901	0.2830	0.062*
C3	0.7676 (4)	0.1855 (4)	0.39170 (18)	0.0559 (8)
H3	0.6696	0.2406	0.4174	0.067*
C6	0.5261 (4)	−0.1657 (4)	0.39954 (16)	0.0487 (8)
H6	0.4769	−0.0643	0.4322	0.058*
C2	0.9438 (4)	0.2392 (4)	0.3958 (2)	0.0597 (9)
H2	0.9875	0.3387	0.4260	0.072*
C7	0.3712 (5)	−0.2990 (5)	0.3805 (2)	0.0693 (10)
H7A	0.4164	−0.4013	0.3495	0.104*
H7B	0.2786	−0.2355	0.3500	0.104*
H7C	0.3208	−0.3444	0.4300	0.104*
C8	0.6711 (5)	−0.2629 (5)	0.4495 (2)	0.0761 (11)
H8A	0.6199	−0.3035	0.4996	0.114*
H8B	0.7693	−0.1786	0.4602	0.114*
H8C	0.7157	−0.3681	0.4202	0.114*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
O1	0.0302 (11)	0.0505 (12)	0.0864 (15)	0.0012 (9)	−0.0025 (10)	−0.0011 (11)
N1	0.0288 (13)	0.0493 (13)	0.0595 (15)	0.0029 (11)	−0.0026 (10)	−0.0055 (11)
N2	0.0307 (14)	0.0628 (16)	0.086 (2)	−0.0005 (12)	−0.0039 (13)	−0.0031 (14)
C4	0.0325 (15)	0.0424 (15)	0.0617 (18)	−0.0002 (12)	−0.0060 (13)	−0.0027 (14)
C5	0.0355 (16)	0.0499 (16)	0.0586 (17)	−0.0024 (13)	−0.0038 (13)	−0.0008 (14)
C1	0.0334 (16)	0.0518 (17)	0.069 (2)	0.0086 (14)	0.0035 (14)	−0.0014 (14)
C3	0.0353 (16)	0.0655 (19)	0.0669 (19)	0.0006 (15)	−0.0020 (14)	−0.0129 (16)
C6	0.0407 (16)	0.0520 (17)	0.0532 (17)	0.0002 (14)	−0.0043 (13)	0.0040 (14)
C2	0.0405 (17)	0.0628 (19)	0.075 (2)	−0.0027 (15)	−0.0125 (15)	−0.0133 (16)
C7	0.066 (2)	0.071 (2)	0.071 (2)	−0.0228 (19)	0.0010 (17)	0.0087 (18)
C8	0.063 (2)	0.085 (2)	0.081 (2)	0.0034 (19)	−0.0120 (19)	0.025 (2)

Geometric parameters (Å, °)

O1—C5	1.408 (3)	C3—C2	1.354 (4)
O1—H1	0.8200	C3—H3	0.9300
N1—C1	1.351 (4)	C6—C8	1.515 (4)
N1—C3	1.367 (3)	C6—C7	1.522 (4)
N1—C4	1.466 (3)	C6—H6	0.9800
N2—C1	1.310 (3)	C2—H2	0.9300
N2—C2	1.362 (4)	C7—H7A	0.9600
C4—C5	1.516 (3)	C7—H7B	0.9600
C4—C6	1.521 (4)	C7—H7C	0.9600
C4—H4	0.9800	C8—H8A	0.9600
C5—H5A	0.9700	C8—H8B	0.9600
C5—H5B	0.9700	C8—H8C	0.9600
C1—H1A	0.9300
C5—O1—H1	109.5	N1—C3—H3	126.9
C1—N1—C3	106.6 (2)	C8—C6—C4	111.6 (2)
C1—N1—C4	126.5 (2)	C8—C6—C7	110.0 (3)
C3—N1—C4	126.8 (2)	C4—C6—C7	111.6 (2)
C1—N2—C2	105.6 (2)	C8—C6—H6	107.8
N1—C4—C5	109.4 (2)	C4—C6—H6	107.8
N1—C4—C6	110.8 (2)	C7—C6—H6	107.8
C5—C4—C6	115.4 (2)	C3—C2—N2	110.1 (3)
N1—C4—H4	107.0	C3—C2—H2	125.0
C5—C4—H4	107.0	N2—C2—H2	125.0
C6—C4—H4	107.0	C6—C7—H7A	109.5
O1—C5—C4	112.3 (2)	C6—C7—H7B	109.5
O1—C5—H5A	109.1	H7A—C7—H7B	109.5
C4—C5—H5A	109.1	C6—C7—H7C	109.5
O1—C5—H5B	109.1	H7A—C7—H7C	109.5
C4—C5—H5B	109.1	H7B—C7—H7C	109.5
H5A—C5—H5B	107.9	C6—C8—H8A	109.5
N2—C1—N1	111.6 (3)	C6—C8—H8B	109.5
N2—C1—H1A	124.2	H8A—C8—H8B	109.5
N1—C1—H1A	124.2	C6—C8—H8C	109.5
C2—C3—N1	106.1 (3)	H8A—C8—H8C	109.5
C2—C3—H3	126.9	H8B—C8—H8C	109.5
C1—N1—C4—C5	−115.0 (3)	C1—N1—C3—C2	−0.8 (3)
C3—N1—C4—C5	69.3 (3)	C4—N1—C3—C2	175.7 (2)
C1—N1—C4—C6	116.8 (3)	N1—C4—C6—C8	−51.7 (3)
C3—N1—C4—C6	−59.0 (3)	C5—C4—C6—C8	−176.6 (2)
N1—C4—C5—O1	−61.5 (3)	N1—C4—C6—C7	−175.2 (2)
C6—C4—C5—O1	64.2 (3)	C5—C4—C6—C7	59.9 (3)
C2—N2—C1—N1	0.0 (3)	N1—C3—C2—N2	0.8 (4)
C3—N1—C1—N2	0.5 (3)	C1—N2—C2—C3	−0.5 (4)
C4—N1—C1—N2	−175.9 (2)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N2i	0.82	1.93	2.751 (3)	176
C1—H1A···O1ii	0.93	2.43	3.353 (4)	173
C4—H4···Cgii	0.98	2.86	3.716 (4)	146

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