Author/Authors :
Estelle Marchal، نويسنده , , Philippe Uriac، نويسنده , , Béatrice Legouin، نويسنده , , Loïc Toupet، نويسنده , , Pierre Van de Weghe، نويسنده ,
Abstract :
We have developed a gold(I)-catalyzed intramolecular cyclization of γ- and δ-alkyne acids in mild conditions yielding various alkylidene lactones. Whereas a slight electronic effect of the R group was observed on the regioselectivity, bulky substituents on the R group bearing the alkyne strongly modify the reactivity. The cycloisomerization of o-alkynylbenzoic methyl esters was achieved rather with AuCl3 as catalyst owing the presence of water affording exclusively the isocoumarins.