[Alkylation of delta 6-octalone-1]

In connection with the synthesis of shwarone (II), a sesquiterpinoid with interesting pharmacological properties, some results on the alkylation in the 9-position of the model substance delta6-octalone-1 (VI) are reported. Methylation, especially if carried out in polar aprotic solvents, gives mainly the trans derivative, this being the type needed for synthesis of compound (II); alkylation with allylbromides and propargyl gives mainly the cis isomer.