3-Methyl­amino-3-phenyl­propan-1-ol

Wolfgang Frey; Mohammad M Ibrahim; Basem F Ali; Volker Jäger

doi:10.1107/S160053681203694X

. 2012 Sep 5;68(Pt 10):o2857. doi: 10.1107/S160053681203694X

3-Methylamino-3-phenylpropan-1-ol

Wolfgang Frey ^a, Mohammad M Ibrahim ^b, Basem F Ali ^b, Volker Jäger ^a,^*

PMCID: PMC3470215 PMID: 23125659

Abstract

The title compound, C₁₀H₁₅NO, is an amino alcohol with the hydroxy group residing on the terminal C atom. Apart from the hydroxy group and the phenyl ring, all non-H atoms are almost coplanar. In the crystal, classical O—H⋯N and N—H⋯O hydrogen bonds connect the molecules into centrosymmetric dimers [R ₂ ²(12) descriptor] and tetrameric units [R ₄ ⁴(8) descriptor] as ring motifs, consolidating a three-dimensional network.

Related literature

For the syntheses of amino alcohols from isoxazolidines, isoxazolines and isoxazolinium salts, see: DeShong & Leginus, (1983 ▶); Henneböhle et al. (2004 ▶); Ibrahim (2009 ▶); Jäger & Buss, (1980 ▶); Jäger et al. (1985 ▶, 2010 ▶); Jäger & Colinas (2002 ▶); Lubell et al. (1991 ▶). For hydrogen-bond motifs see: Bernstein et al. (1995 ▶). For standard bond lengths, see: Allen et al. (1987 ▶).

Experimental

Crystal data

C₁₀H₁₅NO
M _r = 165.23
Monoclinic,
a = 5.9816 (8) Å
b = 23.8962 (19) Å
c = 7.4653 (8) Å
β = 111.119 (7)°
V = 995.40 (19) Å³
Z = 4
Cu Kα radiation
μ = 0.56 mm⁻¹
T = 293 K
0.80 × 0.50 × 0.20 mm

Data collection

Siemens P4 diffractometer
3535 measured reflections
1704 independent reflections
896 reflections with I > 2σ(I)
R _int = 0.087
3 standard reflections every 100 reflections intensity decay: 3%

Refinement

R[F ² > 2σ(F ²)] = 0.071
wR(F ²) = 0.201
S = 1.04
1704 reflections
119 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.22 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Data collection: XSCANS (Bruker, 1996 ▶); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 2008 ▶); software used to prepare material for publication: XP in SHELXTL-Plus.

Supplementary Material

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S160053681203694X/im2389sup1.cif

e-68-o2857-sup1.cif^{(21KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S160053681203694X/im2389Isup2.hkl

e-68-o2857-Isup2.hkl^{(84KB, hkl)}

Supplementary material file. DOI: 10.1107/S160053681203694X/im2389Isup3.cml

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
N1—H1B⋯O1ⁱ	1.02 (4)	2.06 (3)	3.023 (4)	157 (2)
O1—H1A⋯N1ⁱⁱ	1.12 (4)	1.70 (4)	2.815 (3)	176 (3)

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Symmetry codes: (i) Inline graphic ; (ii) .

Acknowledgments

We thank the German Academic Exchange Service (DAAD) for PhD scholarship to MMI.

supplementary crystallographic information

Comment

Isoxazolidines, isoxazolines, and isoxazolinium salts are useful intermediates for syntheses of 1,3-amino alcohols by reduction with cleavage of the N–O bond (DeShong & Leginus, 1983; Jäger & Buss, 1980; Jäger et al., 1985; Jäger & Colinas, 2002; Henneböhle et al., 2004; Jäger et al., 2010). The structures and conformations of previously synthesized amino alcohols were all assigned on the basis of analytical as well as IR, ¹³C and ¹H NMR data. When the 2-methyl-3-phenylisoxazolidine-3-carbonitrile was heated to reflux with lithium aluminium hydride in ether (abs.), the title compound I was formed in good yield. The starting isoxazolidine had been obtained from the corresponding N-methyl-isoxazolinium salt by cyanide addition (Henneböhle et al., 2004; Ibrahim, 2009; Jäger et al. 2010). The formation of the amino alcohol I was rationalized elsewhere (Ibrahim, 2009). The title compound I is already known from other routes (Lubell et al., 1991), yet, the crystal structure of I has not been published so far. We herein report the synthesis and the crystal structure of I, along with the supramolecular motifs present in the crystal lattice.

The asymmetric unit of I consists of one amino alcohol molecule with bond distances and angles in the normal range (Allen et al., 1987). The molecule, a primary alcohol and a secondary amine, adopts a planar zigzag-chain conformation (C1/C2/C3/N1/C4 almost coplanar), with both the hydroxy and the phenyl group being out-of-plane. The hydroxy and the phenyl group enclose dihedral angles of -60.3 (4)° and -63.0 (3)°, respectively, with the atoms of the carbon-chain (hydroxyl-O1/phenyl-C5-C1-C2-C3), see Fig. 1. In the crystal structure, molecules are hydrogen-bonded through the hydroxy groups as well as the amino groups (Table 1) giving rise to a three-dimensional network. The cooperative hydrogen bonds (alternating between hydroxy and amino groups) connect the molecules into chains down the crystallographic a axis (Fig. 2). These chains consist of alternating centrosymmetric dimers, with each dimer further interacting through the hydroxyl and amino groups with the adjacent one to form tetrameric units (Fig. 2). In terms of graph-set description, the hydrogen-bonded molecules might be described as forming two types of rings (Bernstein et al., 1995), the centrosymmetric dimers being R₂²(12) while R₄⁴(8) represents the descriptor for the tetramer units. These interactions consolidate a three-dimensional network.

This amino alcohol conformation in the crystal found here is in contrast to the conformations elucidated in solution on the basis of IR dilution experiments and extensive collections of ¹³C and ¹H NMR data, notably coupling constants and substituent increments - there intramolecular hydrogen bonds O—H···N prevail to form monomers with chair-like arrangements (Jäger & Buss, 1980).

Experimental

A solution of 2-methyl-3-phenylisoxazolidine-3-carbonitrile (150 mg, 0.80 mmol) in anhydrous diethylether (5 ml) at 0°C was added to a suspension of LiAlH₄ (61.0 mg, 1.6 mmol, 2 eq) in anhydrous diethylether (15 ml) and stirred for 30 min. The mixture was allowed to warm up to room temperature and stirred for 1 h. The reaction mixture was then heated to reflux for 12 h. The solution was cooled to r.t., then at 0°C with vigorous stirring. H₂O (0.5 ml), 5% NaOH (0.5 ml), and H₂O (1.5 ml) were added sequentially. The reaction mixture was extracted with ether (4 x 15 ml) and CH₂Cl₂ (2 x 10 ml). The organic layers were dried over Na₂SO₄. The solvent was evaporated in vacuo (5 mbar, 40°C) to afford the amino alcohol I in analytically and spectroscopically pure form as a colorless solid [100 mg, 84%, m.p. 56–57°C; lit. 56–57°C (Lubell et al., 1991)]. Crystallization of the solid from ether afforded colorless crystals suitable for crystal structure determination. Analysis for C₁₀H₁₅NO, Calc.: C 72.69, H 9.15, N 8.48; Found: C 72.39, H 9.11, N 8.07.