A Chemical Study of Virginia Tobacco Flavour (Nicotiana tabacum L.) II. Isolation and synthesis of cis-2-isopropenyl-8-methyl-1,2,3,4-tetrahydro-1-naphthalenol and 3-isopropenyl-5-methyl-1,2-dihydronaphthalene

Gas liquid chromatography allowed isolation of the novel cis-2-isopropenyl-8-methyl-1,2,3,4-tetrahydro-1-naphthalenol ( A ) and its dehydration product, 3-isopropenyl-5-methyl-1,2-dihydronaphthalene ( B ), from two small subfractions of Virginia tobacco condensate. Both these norsesquiterpenes were identified on spectral grounds and synthesized from 1-methylnaphthalene in a way (9 steps) that also afforded the «non-natural», trans-alcohol A ′. The possible biogenesis of A and B in tobacco is briefly outlined.