2-(Tricyclo[3.3.1.13,7]dec-2-ylamino)ethanol hemihydrate

Grant A Boyle; Thavendran Govender; Hendrik G Kruger; Oluseye K Onajole

doi:10.1107/S1600536808016851

. 2008 Jun 7;64(Pt 7):o1228. doi: 10.1107/S1600536808016851

2-(Tricyclo[3.3.1.1^3,7]dec-2-ylamino)ethanol hemihydrate

Grant A Boyle ^a, Thavendran Govender ^b,^*, Hendrik G Kruger ^a, Oluseye K Onajole ^a

PMCID: PMC2961807 PMID: 21202865

Abstract

The title adamantane derivative, C₁₂H₂₁NO·0.5H₂O, was synthesized as part of an investigation into the biological activities of cage amino–alcohol compounds as potential anti-tuberculosis agents. The structure displays intermolecular O—H⋯N, N—H⋯O, O—H⋯O hydrogen bonding and a layered packing structure with distinct hydrophilic and hydrophobic regions. The water molecule lies on a twofold rotation axis.

Related literature

For related literature, see: Bogatcheva et al. (2006 ▶); du Pont de Nemours and Co. (1969 ▶); Lee et al. (2003 ▶); Tripathi et al. (2006 ▶).

Experimental

Crystal data

C₁₂H₂₁NO·0.5H₂O
M _r = 204.31
Monoclinic,
a = 11.6739 (3) Å
b = 6.5043 (2) Å
c = 28.6241 (7) Å
β = 99.8620 (10)°
V = 2141.33 (10) Å³
Z = 8
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 173 (2) K
0.56 × 0.43 × 0.18 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: none
13147 measured reflections
2584 independent reflections
2352 reflections with I > 2σ(I)
R _int = 0.058

Refinement

R[F ² > 2σ(F ²)] = 0.042
wR(F ²) = 0.112
S = 1.07
2584 reflections
141 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.39 e Å⁻³
Δρ_min = −0.19 e Å⁻³

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: SAINT-Plus (Bruker, 1999 ▶); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: Mercury (Macrae et al., 2006 ▶) and ORTEP-3 (Farrugia, 1997 ▶); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003 ▶).

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808016851/hg2403sup1.cif

e-64-o1228-sup1.cif^{(18.1KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808016851/hg2403Isup2.hkl

e-64-o1228-Isup2.hkl^{(124.4KB, hkl)}

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—H1C⋯N1ⁱ	0.84	1.86	2.7007 (12)	175
N1—H1B⋯O1Wⁱⁱ	0.849 (16)	2.398 (16)	3.2241 (12)	164.6 (14)
O1W—H1W⋯O1ⁱⁱⁱ	0.863 (16)	1.963 (17)	2.8147 (12)	168.7 (16)

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

Acknowledgments

We thank Dr Manuel Fernandes of the Jan Boeyens Structural Chemistry Laboratory at the University of the Witwatersrand for his assistance in the acquisition of the crystallographic data. This work was supported by grants from the National Research Foundation (South Africa), GUN 2046819, the University of KwaZulu–Natal and Aspen Pharmacare.

supplementary crystallographic information

Comment

The title compound, an adamantane derivative, was synthesized as part of an ongoing study to evaluate the biological activity of such compounds as potential anti-tuberculosis agents (Bogatcheva et al. (2006), Lee et al. (2003), Tripathi et al. (2006)). Although the compound is known (du Pont de Nemours and Co.; 1969), its crystal structure has not been reported.

The compound contains a polycyclic (lipophilic) hydrocarbon region, polar amine and hydroxyl units, and crystallizes with half a water molecule in the asymmetric unit (Fig.1)- the water molecule being situated on a crystallographic 2-fold axis at (1, y, 3/4). The title molecule exhibits several C–C bond lengths in the adamantane skeleton that deviate from the expected value of 1.54 Å. This has been observed previously and is typical for these types of compounds.

The structure exhibits intermolecular hydrogen bonding between O1 and N1 of adjacent molecules as well as between O1 and O1W of the water molecule (Fig. 2). There is also a complex network of short contacts between the molecules in structure. These intermolecular interactions result in a layered structure with distinct hydrophilic and hydrophobic regions (Fig. 3). The adamantane skeleton forms the hydrophobic layer while the polar hydroxyl and amino moeties constitute the hydrophilic region.

Experimental

A mixture of 2-adamantanone (2 g, 13 mmol) and 2-aminoethanol (1 g, 16 mmol) in 20 ml of methanol was stirred under dinitrogen atmosphere at room temperature for 2 h. The mixture was cooled to zero degrees using an external ice bath after with NaBH₄ (1 g, 26 mmol) was added slowly over a 30 minutes. The mixture was stirred for overnight at room temperature after which it was concentrated in vacuo and excess NaBH₄ was quenched by adding 40 ml of 10% HCl and the product was also extracted as its HCl salt in the process. The aqueous solution was washed with 2x20ml of dichloromethane, after which the aqueous layer was basified (pH 12) with NH₄OH and the product was extracted from the mixture with dichloromethane (2x30ml), the solvent was dried over Na₂SO₄ and concentrated in vacuo. The product was recrystallized from dichloromethane, thereby affording pure 2-aminoethanol adamantane (2 g, 77% yield).