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The synthesis of levetiracetam and its enantiomer by deracemization of (±)-2-bromobutyric acid using either ( S )- or ( R )- N -phenylpantolactam as chiral auxiliaries, followed by S N 2 substitution of the bromine atom by a 2-oxopyrrolidin-1-yl group and amidation of the carboxylic acid, is described.

Enantiomerically pure central and planar chiral ferrocenyl cyanohydrins have been used for the synthesis of previously unreported 5-ferrocenyl-oxazolines and a 5-ferrocenyl-thiazoline where the central chirality lies on the carbon bearing the oxygen or the sulfur atom. The epimerization at C 5 of the oxazoline ring has also been investigated.

Enantiopure fluorinated isoxazolidines and amino polyols were obtained from the 1,3-dipolar cycloaddition of allylic fluorides and Z-α-phenyl-N-methylnitrone under environment-friendly conditions.

A synthesis of ferrocenyl-oxazolines is described using an iodide-mediated ring expansion of N-ferrocenoyl-aziridine-2-carboxylic esters. The ring enlargements take place with full stereocontrol, namely net retention of configuration. Modification of the ester function by a Grignard reaction leads to three new types of ferrocenyl-oxazoline carbinol ligands, which were used as chiral ligands in the asymmetric addition of diethylzinc to benzaldehyde (e.e.s ranging from 46 to 62%). The planar chiral ferrocenyl-oxazoline carbinol ligand gave a very good result (e.e. 90%) in the palladium-catalyzed allylic substitution of 1,3-diphenyl prop-2-enylacetate with dimethyl malonate.

The new allylaminosilanes 2a – c , derived from chiral amines, react with benzaldehyde and pivalaldehyde in the presence of SnCl 4 to give homoallylic alcohols 4a – b with enantiomeric excesses of up to 30%.