3-Methyl-8-methylidene-1,2,4,5,6,7,8,8a-octahydroazulen-6-ol → 3-Methyl-8-methylidene-2,4,5,7,8,8a-hexahydroazulen-6(1H)-one

Participants

Reaction Steps

A solution, cooled to -10°, of 26.7 g of 6-hydroxy-1-methyl-4-methylen-2,3,3a,4,5,6,7,8-octahydroazulene in 1500 ml of acetone was treated dropwise within 30 minutes with 65 ml of Jones reagent (172 mM CrO3). The mixture was poured on to excess ice-cold bicarbonate solution and exhaustively extracted with ether. The organic phase was washed with bicarbonate solution and water, dried with anhydrous magnesium sulphate and concentrated under reduced pressure. The crude product which was obtained in the form of a yellow oil, was fractionated under reduced presdure and yielded 20.5 g (yield 77%) of pure 1-methyl-4-methylen-6-oxo-2,3,3a,4,5,6,7,8-octahydroazulene; b.p.0.005 62°-65°; IR(film)νmax = 3090, 1708, 1640, 1450/38, 1345, 1322, 1305, 1262, 1240, 1195, 1140, 1108, 950, 900, 800 cm-1. The compound has a herb-like, camphorous, terpin oil-like odour.

Provenance & Evidence