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Updated: Aug 29, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Characteristics of the two frontier orbital interactions in the Diels-Alder cycloaddition
Claude Spino1, Hadi Rezaei, Yves L Dory
1Université de Sherbrooke, Département de Chimie, 2500 Boulevard Université, Sherbrooke, QC, Canada J1K 2R1. claude.spino@usherbrooke.ca
Abstract:
Two electron-deficient dienes were reacted with a series of twelve electron-poor and electron-rich dienophiles to give, in some cases, the corresponding Diels-Alder adducts. Clear differences in the roles played by the two frontier orbital interactions emerged. It was demonstrated that in the case of normal Diels-Alder cycloadditions, the FMO theory could predict the relative reactivities between dienophiles, while in the case of inverse-electron demand Diels-Alder reactions, it could not. It was shown that the dissymmetry in electron-rich dienophiles increases their reactivities.
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