Studies on the Components of Citrus Species (Rutaceae). III

Studies on the Constituents of Orange Oil. (2)

Abstract

Auraptene, m.p. 68°, obtained as the crystalline component of orange oil and confirmed as 7-hydroxycoumarin geranyl ether, was catalytically reduced with platinum black at ordinary temperature and pressure from which the corresponding phenol, i.e. 7-hydroxycoumarin, was obtained. As a model experiment to confirm this fact, various ethers of hydroxycoumarins were prepared and their catalytic reduction was carried out, by which it was observed that the aromatic ethers possessing β, γ-unsaturated alkyl side chain easily underwent hydrogenolysis to give the corresponding phenols. 7-Hydroxycoumarin was also obtained by pyrolysis of auraptene.