Scheme 4. (A) Diethyl(α-acetoxymethyl)vinylphosphonate (DVP) reacts slowly with glycine to form a double adduct of DVP on glycine. In the presence of DABCO, this reaction proceeds roughly 15-fold faster via a DABCO-DVP adduct, which possesses a significant lifetime and can be isolated. (B) Depending on the electron-withdrawing group (EWG) and leaving group (LG), MAs possess vastly different reactivity towards nucleophiles, just as different nucleophiles show different reactivity towards MAs. These trends can act as a general guideline for the reader.