Nootkatanes

Nonacarbonyldilron, 110-111 Nootkatanes, 31 N-Noiapomorphine, 236 Norbornene, 382, 383 Noicaradienes, 264 Norcocainc, 384 Noiit, 52... 

Rearrangement of a 10-epieudesmane derivative to a nootkatane derivative. Treatment of the cyclopropyl ketone (1) with BF3 at 20° leads to (2) in 46% yield (GLC) together with four minor, unidentifled products. The reaction... 

Chamaecyparis nootkatensis) and later from grapefruit Citrus paradisi) juice. It is responsible for the typical grapefruit flavor, and is commercially produced synthetically. Other examples of nootkatane type from woody parts of plants are (+)-valerianol (245) from roots of Valeriana officinalis, and a-vetivone (246), an important component of vetiver oil (314). Of several eremophilanolides (146), mention may be made of furanoeremophilanolide 247 from roots of Ligularia hodgsoni. Over 50 new furanoeremophilanes have been isolated from roots of various Euryops spp. (52). 

From the roots of Aristolochia indica, the tetracyclic sesquiterpenes ishwarane (252) and ishwarone (253) have been isolated (314). A few other related compounds are known. Biogenetically, they appear to be derived from the nootkatane cation (240). 

Irradiation of lumiproducts in aqueous acetic add with UV light above 300 nm brings about photorearrangement to SpirocycHc dienones. This type of transformation was used for the conversion of the nootkatane sesquiterpenes 3,4-dehydronootkatone (153) into the spirovetivane anhydro-P-rotunol (155) and in the synthesis of P-vetivone and 4-epi-P-vetivone from dehydro-P-vetivone. ... 

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