Theoretical illustration on the catalytic effect of alanine methyl ester nitrate ionic liquid on the Diels-Alder reaction between cyclopentadiene and methacrylate

► The [AME][NO3]-catalyzed Diels-Alder reaction between cyclopentadiene and methacrylate is studied theoretically. ► [AME][NO3] plays a role of Lewis acid to promote the reaction. ► The catalytic active center is the NH3 group in [AME]+ cation. ► The optimal molar ratio among two reactants and the catalyst may be 1:1:2.