The chemistry of triterpenes and related compounds. Part XLVI. Some novel products from the ozonolysis of methyl acetylbetulinate

Abstract

Ozonolysis of methyl acetylbetulinate (II) gives number of products in addition to the nor-ketone (V) formed by the normal fission of the isopropenyl double-bond. They include the Baeyer–Villiger oxidation product (VIII) of the nor-ketone and two trisnor-compounds. In one of these (XVIII) the isopropenyl group has been lost and a Δ^18,19 double-bond has been formed at the carbon to which it was attached. In the other (XI) the isopropenyl group has been replaced by hydrogen. A possible mechanism for the formation of these products is discussed.

Ozone has been shown to be an efficient oxidant for the conversion of the saturated alcohol lupanol into lupanone.