Paul W. Groundwater, Toqir Sharif, Andrea Arany, David E. Hibbs, Michael B. Hursthouse, Ian Garnett and Miklós Nyerges
A novel synthesis of didehydroamino acid (DDAA) esters 5 is described, starting from aldimines 2. The mechanism for this reaction has been shown to involve the cycloaddition of an azomethine ylide 3 to an imine 2, followed by the base-catalysed ring-opening of the resulting imidazolidine intermediate 7. This novel method has also been extended to the synthesis of DDAA esters 5 catalysed by imines.