Abstract
Cyclopropyldiphenylsulfonium salt, a famous ylide precursor previously extensively
employed in the preparation of cyclic compounds, has been successfully utilized as
an efficient allylation reagent in this work. The copper-catalyzed reactions of cyclopropyldiphenylsulfonium
trifluoromethanesulfonate with amines in the presence of an appropriate ligand provided
the N-allylated products in good yields. Aliphatic/aromatic amines and primary/secondary
amines were all converted under mild reaction conditions. This protocol was also applicable
to N-functionalization of drug molecules, supplying the corresponding N-allylated compounds in satisfactory yields. The reaction, which showed good functional
group tolerance with a wide range of substrates and excellent chemoselectivity, offers
an interesting method for the synthesis of N-allyl amines.
Key words
sulfonium salts - amines - copper - allylation - catalysis
