Highly Regioselective Friedel–Crafts Reactions of Electron‐Rich Aromatic Compounds with Pyruvate Catalyzed by Lewis Acid‐Base: Efficient Synthesis of Pesticide Cycloprothrin

An efficient synthesis of aromatic lactate esters is reported via highly regioselective Friedel–Crafts reactions of electron‐rich aromatic compounds with pyruvate ester promoted by TiCl4 in the presence of basic Al2O3. The utility of the reaction is shown by the efficient synthesis of the pesticide cycloprothrin in high yield.