Terpenoids-LXVI: ring enlargement produced by the alkaline fusion of ω-bromolongifolene

Abstract

By analogy with ω-bromocamphene, ω-bromolongifolene on fusion with alkali, but at a comparatively higher temperature, gives several monomeric and dimeric products as a result of ring enlargement. The monomeric products have been characterized as longihomocamphenilone (VIII) and longi-isohomocamphenilone (IX). The dimeric products are composed of a mixture of longifolenyl ethers and the kinetic dimers. lead tetraacetate oxidation of longifolene, according to the method of Ourisson, has been found to yield, not only longihomocamphenilone and longidione, but also a crystalline alcohol, identified as isolongifolol (XI).