Europium(III)triflate has been proved to be an effective catalyst for intramolecular cyclization of aryl-substituted carboxylic acid to afford arylated γ-butyrolactone. Various attractive features, such as broad substrate scope, a wide range of functional group tolerance, operational simplicity, complete atom economy, and good-to-excellent yields have made this new protocol more appealing. Moreover, this method provides a practical alternative to the existing catalysts.
Key words
γ-butyrolactones - lanthanide catalyst [Eu(OTf)
3] - ω-alkenoic acid - intramolecular hydroacyloxylation reaction - O-containing heterocycles