Staudinger synthesis

The first step is a nucleophilic attack by the imine nitrogen on the carbonyl carbon to generate a zwitterionic intermediate.

Under photochemical and microwave conditions the intermediate's 4π-electron system cannot undergo a disrotatory ring closure to form the β-lactam, possibly because the two double bonds are not coplanar.

[12] If the ring closure step is rate-determining, stereochemical predictions based on torquoselectivity are reliable.

The ketene substituent affects the transition state by either speeding up or slowing down the progress towards the β-lactam.

[11] Reviews on asymmetric induction of the Staudinger synthesis, including the use of organic and organometallic catalysts, have been published.

In 2014, Doyle and coworkers reported a one-pot, multicomponent Staudinger synthesis of β-lactams from azides and two diazo compounds.

The solvent used for this reaction is dichloromethane (DCM) and the solution needs to rest for 3 hours at room temperature.