1-Aminovinylphosphonate esters as substrates for the Diels-Alder reaction: First synthetic and theoretical study

The Diels‐Alder reaction of 1‐aminovinylphosphonate esters has been studied for the first time as a suitable procedure leading to quaternary carbocyclic α‐aminophosphonates. The reaction is influenced by steric effects at the phosphonate functionality (bulky groups hinder the reaction) and electronic effects at the amino group (electron‐withdrawing substituents increase the reaction rate). The exo/endo ratio is constant, and no influence of the solvent is observed. The experimental results have been rationalized by DFT methods.This work was supported by the Ministerio de Economía y Competitividad (grants CTQ2013–40855-R to C.C. and CTQ2016–76155-R to P.M.) and the Gobierno de Aragón–FEDER (Biological and Computational Chemistry Group E34_R17 and Amino acids and Peptides Group E19_17R). M.M.J.-A. thanks the Gobierno de Aragón-FSE for predoctoral grant.Peer reviewe