Isomerization of Caryophyllene Oxide Catalyzed by Solid Acids and Bases

Article abstract of DOI:10.1246/bcsj.66.218

The reaction of caryophyllene oxide over eleven catalysts of solid acids and bases gave 4,5-dihydrocaryophyllen-5-one (III), (1R, 5S, 8R, 9R)-4,4,8-trimethyltricyclo<6.3.1.0^1,5>dodeca-2-en-9-ol (IV), (2S, 5R, 9R)-caryophylla-1(12),8(15)-dien-9-ol (V), (2S, 5R, 9R)-caryophylla-1(12),7-dien-9-ol (VI), and (2S, 5R, 9S)-caryophylla-1(12)-7-dien-9-ol (VII).A large amount of III was formed together with IV over FeSO4 and Zr(SO4)2.Allylic alcohols (V, VI, and VII) were preferentially given by Al2O3-II and TiO2-ZrO2 in >74percent selectivity: 96percent on TiO2-ZrO2.Other catalysts formed three to five species of the products uniformly.