Study Based on Electronic Descriptors of the Diastereoselective Aza-Diels-Alder Cycloaddition of [(1r)-10-(N,n-Diethylsulfamoyl)isobornyl] 2h-Azirine-3-Carboxylate to E,e-1,4-Diacetoxy-1,3-Butadiene

Abstract

Cycloaddition of chiral [(1R)-10-(N,N-diethylsulfamoyl)isobornyl] 2H-azirine-3-carboxylate to E,E-1,4-diacetoxy-1,3-butadiene shows complete diatereoselectivity giving a single cycloadduct (-)Our main objective is to identify electronic/steric parameters capable of describing the observed tendencies of this reaction. The results of the calculations conclude that: even though the steric factors can play an important role at the initial steps of the reaction, at the transition states the behavior of several electronic parameters; like hardness, polarizability, aromaticity, charge transfer, etc is decisive enough to justify the obtained product. Finally, this work summarizes an exhaustive analysis of electronic descriptors and empirical reactivity principles, reaching a definitive and comprehensive explanation to the observed experimental result.

Simple descriptors for assessing the outcome of aza-Diels–Alder reactions

“…Previous studies have systematically reported the exo cycloadducts to be sterically less hindered, and thus thermodynamically more stable than their endo counterparts. 6,9,10,17,41 In this study, however, we noticed the endo products with R 1 ¼ tBu to be slightly more stable than their exo analogues when considering their energy at 0 K relative to the free reactants, DE Prod . These results are depicted in Fig.…”

“…6,9,10,17,41 In this study, however, we noticed the endo products with R 1 ¼ tBu to be slightly more stable than their exo analogues when considering their energy at 0 K relative to the free reactants, DE Prod . These results are depicted in Fig.…”