Esters as Acylating Reagent in a Friedel-Crafts Reaction: Indium Tribromide Catalyzed Acylation of Arenes Using Dimethylchlorosilane

The Friedel-Crafts acylation of arenes with esters by dimethylchlorosilane and 10 mol % of indium tribromide has been achieved. The key intermediate RCOOSi(Cl)Me-2 is generated from alkoxy esters with the evolution of the corresponding aikanes. The scope of the alkoxy ester moiety was wide: tert-butyl, benzyl, allyl, and isopropyl esters were successful. In addition. we demonstrated the direct synthesis of the indanone intermediate 11 of salviasperanol from ester 10.