Study on the Synthesis of Thujopsane-8, 9-diol from Thujopsene

Thujopsane-8, 9-diol was synthesized by the dihydroxylation of thujopsene using KMnO₄ as oxidant, tertiary-butyl alcohol/H₂O(2:1, volume ratio) as solvent in the presence of NaOH. The effects of reaction conditions on the dihydroxylation reaction were investigated and the optimal reaction conditions were reaction temperature 40 ℃, molar ratio of raw materials n(KMnO₄): n(thujopsene)=1.8:1, reaction time 3 h, mass fraction of KMnO₄ aqueous solution 5%. Under these conditions, the conversion rate of thujopsene was 98.3%, the yield and selectivity of thujopsane-8, 9-diol were 88.7% and 90.2%, respectively. The structure of the product was characterized by GC-MS, FT-IR and ¹H NMR, and confirmed to be thujopsane-8, 9-diol.