Acid-Catalyzed Cascade Ring-Opening and Addition Reactions ofArylvinylcyclopropenes with α,β-Unsaturated Substrates,Scope and Limitations

摘要

Catalyzed by Al(III) catalyst, arylvinylcyclopropenes react with α,β-unsaturated substrates smoothly toproduce the Diels—Alder adducts in moderate to good yields through a cascade ring-opening reaction/Diels—Alder cycloaddition. On the other hand, strong Bronsted acid TfOH can promote the cascadeintramolecular Friedel -Crafts/1,4-addition reaction to produce indene derivatives in moderate to goodyields under mild conditions. The acidity of the catalysts plays a key role in these reactions.