Technical Note:
1.Friedel-Crafts Alkylation: Chiral phosphoric acids were used as catalysts for the Friedel-Crafts alkylations of indolyl enones while both a ruthenium complex and chiral phosphoric acids were used as catalysts for sequential olefin cross-metathesis and Friedel-Crafts alkylations of allyloxymethyl or allylaminomethyl indoles and enones.
Reference:
1. Angew. Chem. Int. Ed., 2009, 48, 7428-7431.