The scope of catalytic enantioselective tandem carbonyl ylide formation-intramolecular [3 + 2] cycloadditions.
Catalytic enantioselective tandem carbonyl ylide formation-intramolecular 1,3-dipolar cycloaddition reactions of 2-diazo-3,6-diketoesters show promising scope in terms of asymmetric induction as the tethered alkene/alkyne dipolarophile component is varied. Cycloadditions were found to occur in moderate to very good yields, with a difference in ee exhibited by the electronically different 2-diazo-3,6-diketoesters 1, 25 and 33, 34. Values for ee of up to 90% for alkene dipolarophiles and up to 86% for alkyne dipolarophiles were obtained.
Hodgson
David M
DM
Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QY, UK. david.hodgson@chem.ox.ac.uk
Labande
Agnès H
AH
Pierard
Françoise Y T M
FY
Expósito Castro
María A
MA