A process for the carbonylation of allylic alcohols such as nerolidol, farnesol, or their monocyclic analogues with carbon monoxide at a pressure of at least 30 bar in the presence of a polar solvent and a palladium halide catalyst, optionally an alkali metal halide salt, and optionally an alcoholic solvent. The carbonylated product may then be reduced to the corresponding alcohol, which is cyclized in the presence of Lewis or Bronsted acids to afford an ambergris fragrance compound.