Collect. Czech. Chem. Commun. 1979, 44, 2393-2400

Radical cyclisation reactions of ketones with alkenes initiated by silver(II) and lead(IV) oxides

Milan Hájek, Přemysl Šilhavý and Jaroslav Málek

Institute of Chemical Process Fundamentals, Czechoslovak Academy of Sciences, 165 02 Prague 6-Suchdol


Acetone and 2,4-pentanedione react with α-methylstyrene in the presence of the title oxides to form 2,5-dimethyl-5-phenyl-4,5-dihydrofuran and its 3-acetyl derivative, respectively, in about 70% yields. The reaction of these ketones with styrene, which is more prone to telomerisation and polymerisation reactions, gives the corresponding 5-phenylsubstituted 4,5-dihydrofuran derivatives in lower yields (30-40%). Cyclization reaction of acetophenone with 1-octene induced by silver(II) oxide produces 4-n-hexyl-α-tetralone and decanophenone in a 70 : 30 ratio.