Grant A. Boyle

NMR elucidation of a novel (S)-pentacyclo-undecane bis-(4-phenyloxazoline) ligand and related derivatives.

The NMR elucidation of a novel ligand (S)‐pentacyclo‐undecane bis‐(4‐phenyloxazoline) and related pentacyclo‐undecane (PCU) derivatives is reported. Two‐dimensional NMR proved to be a powerful technique in overcoming the difficulties associated with the elucidation of these compounds when only one‐dimensional NMR data is utilized. A chiral substituent was introduced to both ‘arms’ of the PCU skeleton to produce derivatives 1–3. These derivatives display C1 symmetry with all thecage atoms being nonequivalent. Owing to overlapping of peaks in the 1H spectra, identification of these diastereomeric protons was very difficult. The 13C spectra gave rise to clear splitting of the nonequivalent carbons. This is unusual compared to similar PCU derivatives with chiral substituents as splitting of all the diastereomeric cage carbons has not yet been reported. Nuclear Overhauser enhancement spectroscopy (NOESY) correlations of derivatives 1–3 confirm the different conformations of the molecule in which the side ‘arms’ occupy different orientations with respect to cage moiety. Copyright

(4-Hydr­oxy-3-nitro­benz­yl)methyl­ammonium chloride

The title compound, C8H11N2O3 +·Cl−, was synthesized as an intermediate in the development of a new sugar sensor. The structure displays N—H⋯Cl and O—H⋯O hydrogen bonding, as well as weak O—H⋯Cl interactions and π–π stacking (3.298 Å). There are two formula units in the asymmetric unit.

8-(Biphenyl-4-yl)-8-hydroxy­penta­cyclo­[5.4.0.02,6.03,10.05,9]undecan-11-one ethyl­ene ketal

The title compound, C25H24O3, synthesized as a potential chiral catalyst, exhibits a range of C—C bond lengths in the pentacycloundecane cage between 1.5144 (18) and 1.5856 (16) Å. The two benzene rings are not planar with respect to each other, but rather are twisted at a torsion angle of 34.67 (17)°. The molecule has an intramolecular O—H⋯O interaction and participates in two C—H⋯O intermolecular interactions to form a one-dimensional chain.

N-(2-Hydroxy­ethyl)-N-(tricyclo­[3.3.1.13,7]dec-2-yl)benzamide

The title adamantane derivative, C19H25NO2, was synthesized as part of a study into potential antituberculosis agents. The adamantane skeleton displays shorter than normal C—C bond lengths ranging between 1.5230 (15) and 1.5329 (16) Å. The structure displays O—H⋯O hydrogen bonding and an interdigitated layered packing structure with distinct hydrophilic and hydrophobic regions.

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

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.

(S)-(+)-2-Formamido-4-methylpentanoic acid

Boyle, G. A., Govender, T., Kruger, H. G. & Maguire, G. E. M. (2004). Tetrahedron Asymmetry, 15, 2661–2666. Bruker (2005). APEX2 (Version 2.0-1) and SAINT-NT (Version 6.0). Bruker AXS Inc., Madison, Wisconsin, USA. Bruno, I. J., Cole, J. C., Edgington, P. R., Kessler, M., Macrae, C. F., McCabe, P., Pearson, J. & Taylor, R. (2002). Acta Cryst. B58, 389–397. Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838. Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany. organic compounds