ChemInform Abstract: A General Synthesis of Chiral C-4-Alkylated Azetidin-2-ones which are of Potential Use as Intermediates for 1β-Heteroatom-Substituted Carbapenems

A highly diastereocontrolled alkylation at the C-4 position of 4-acetoxyazetidin-2-one (5) employing chiral tin(II) enolates of heteroatom-substituted acetyl derivatives (3a–e) furnishes new synthetic intermediates (6a–e) for 1β-heteroatom-substituted carbapenems (2).