Enantioselective terpene synthesis based on R- ( +)-limonene

The prevalence of a C- common c o r e in diverse C te rpenes has been recognised. A bifun%onal C I 2-cyclopentanoid deriva%: % corresponding to this common-core has been prepared f rom R-(+)-limonene. The enant io-merical ly pure 2 has been e labora ted to severa l sesqui- and d i te rpene skeleta. In par t icular, enant iose lec t ive syntheses of isodaucane sesqui terpene, (+)-apha-namol-I, 3 and a dolabel lane di terpene, 6-araneosene 26 have been accom-plished for t h e f i r s t t ime. A genera l solution to t h e s te reochemica l problem assoc ia ted wi th th i s c lass of compounds has been devised. Syntheses of (-)-daucene 8 and (+)-isoamijiol 17 a r e a lso described