Enantioselective 1,3-Dipolar Cycloadditions with Silver Catalysts
C. Nájera, M. de Gracia Retamosa, J. M. Sansano*
Universidad de Alicante, Spain
22. November 2007 (online)
The 1,3-dipolar cycloaddition reaction can generate four stereocenters with defined stereochemistry in a single step. The authors report on the reaction of azomethine ylides with N-methylmaleimide as dipolarophile in the presence of a chiral silver catalyst. The catalyst itself is insoluble in the reaction solvent and can be recovered and used consecutively up to four times with minimal loss in activity and selectivity.