Recent Advances in the Preparation of Enantiomerically Pure Hydroxylamines from Nitrones

This review covers the recent advances in the synthesis of enantiomerically pure hydroxylamine's employing nitrones as starting materials. Nucleophilic additions of organometallic reagents to nitrones are the most common way for introducing a hydroxyamino group into carbon skeletons with the concomitant formation of a new carbon-carbon bond. Addition of nucleophiles derived from enolates, cyanide or fluorinated derivatives allows the preparation of complex structures. Radical additions and, in particular samarium diiodidemediated reductive coupling of nitrones with carbonyl compounds and α,β-unsaturated esters have also been considered. All these approaches provide efficient methods of preparation of enantiomerically pure hydroxylamine's that are valuable synthetic intermediates. Keywords: Hydrocyanation, hydroxylamines, mannich reaction, nitrones, organometallics, reductive coupling.