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Ring opening of two equivalents of racemic styrene epoxide by benzylamine gives rise to racemic mixture of 2-(benzyl -(2-hydroxy-2-phenylethyl)-amino)-1- phenylethanol, among other diethanolamine products. The racemic mixture is efficiently separated into its enantiomers by complexation with (-) camphor-10-sulphonic acid. The corresponding diastereomeric complex was also characterized by single crystal X-ray diffraction method. This resolution method offers an economically more viable route for the isolation and use of the chiral ligand that has proved to be useful in many asymmetric catalysis reactions. ? ARKAT.

A novel and general method has been developed for the stereoselective construction of 5-hydroxymethyl azabicyclic ring skeletons based on epoxide-initiated cationic cyclization of azides. The key cyclization reaction was systematically studied with the model compound, 3-(1-oxa-spiro[2.4]hept-4-yl)propyl azide 3a, and EtAlCl 2 was found to be an ideal choice as the catalyst. The generality of this transformation was further tested with different ring sizes, where six- and seven-membered epoxyazides 3b,c underwent smooth cyclization to give 5-hydroxymethyl azepine 4b and 5-hydroxymethyl azocine 4c, respectively, as a single detectable diastereomer. This novel methodology was elegantly applied in the stereoselective total synthesis of indolizidine alkaloids 167B and 209D. Further, the enantioselective total synthesis of natural and unnatural indolizidine alkaloids 167B and 209D was accomplished by using Sharpless asymmetric dihydroxylation as a key step.

Two novel chiral rhodium complexes were successfully synthesized from the reaction of chiral bidentate nitrogen ligands with RhCl3-3H2O in ethanol under reflux. Their unusual crystal structures were unambiguously obtained by X-ray analysis. Copyright ? 2001 John Wiley & Sons, Ltd.