Synthetic Studies on Terpenic Compounds. XII. Selective Degradation of the Side Chain in Portulal

Stepwise degradation of the side chain in portulal has been investigated in connection with synthetic studies. Selective cleavage of the double bond in the side chain was achieved by ozonolysis after protection of the endo-double bond by iodoetherification of the corresponding alcohol. Further degradation led to the formation of the γ-lactone via the δ-lactone.