α-Aminophosphonates. III. Cycloaddition anionique-1,3 des esters α,β-insatures: Preparation et transformations des Δ1-pyrrolines
The anions of the 2-azaallylphosphonates 1 react with the α,β-unsaturated esters 2 to yield intermediates 4'.These intermediates form the 2-diethoxyphosphonyl-4-ethoxycarbonylpyrrolidines 4 following a protonation while an elimination of the anion of the