Highly stereocontrolled and concise asymmetric synthesis of the β-lactam framework via a TCC method

Article abstract of DOI:10.1016/S0040-4039(00)74424-8

The conjugate addition of LSA 1 to t-butyl (4S)-4-(trityl)oxy-2-pentenoate 2d followed by aldol condensation with acetaldehyde produces a key intermediate 3 to β-lactam derivatives as a single diastereoisomer in 77% yield.