[8+2] Formal Cycloaddition Reactions of Tropones with Azlactones under Brønsted Acid Catalysis and Synthesis of α-(2-Tropyl), α-Alkyl α-Amino Acids
作者:Francisco Esteban、Ricardo Alfaro、Francisco Yuste、Alejandro Parra、José Luis García Ruano、José Alemán
DOI:10.1002/ejoc.201301774
日期:2014.3
The reaction of tropones with azlactones catalyzed by Bronsted acids affords a variety of dihydro-2H-cyclohepta[b]furan derivatives, corresponding to a formal [8+2] cycloaddition process. They can easily be opened by nucleophiles to afford a new type of α,α-disubstituted α-amino acid (or peptide) containing seven-membered rings at the quaternary position.