Changes of Stereoselectivity in Diels–Alder Reactions by Hydrophobic Solvent Effects and by β‐Cyclodextrin

Abstract

The endo/exo product ratios in Diels–Alder reactions can be changed significantly by use of aqueous solvents. The diastereoselectivity can be described as a quantitative function of solvent-solvophobicity parameters. In some cases, addition of β-cyclodextrin effects, even more drastic changes in the endo/exo ratio as well as the formation of chiral Diels–Alder adducts.