Gold-catalyzed cyclization of allenyl acetal derivatives

• Dhananjayan Vasu,
• Samir Kundlik Pawar and
• Rai-Shung Liu

Beilstein J. Org. Chem. 2013, 9, 1751–1756, doi:10.3762/bjoc.9.202

• Dhananjayan Vasu Samir Kundlik Pawar Rai-Shung Liu Department of Chemistry, National Tsing Hua University, Hsinchu, 30013, Taiwan (ROC) 10.3762/bjoc.9.202 Abstract The gold-catalyzed transformation of allenyl acetals into 5-alkylidenecyclopent-2-en-1-ones is described. The outcome of our

• of the acetate group at the allyl cation intermediate. Keywords: allenyl acetals; 5-alkylidenecyclopent-2-en-1-ones; cyclization; gold catalysis; Introduction Gold-catalyzed cyclization/cycloaddition reactions [1][2][3][4][5] are useful synthetic methods to construct complicated carbo- and

• oxacyclic frameworks. Such cascade reactions have been well studied on various difunctionalized molecules including oxoalkynes [6][7][8][9][10][11][12][13], oxoallenes [14], oxoalkenes [15] and allenyl acetals [16][17][18]. In this cascade sequence, two new rings and three chemical bonds are generated in a