Khusimone (1), one of the main odor-donating compounds of vetiver oil
is subject of the following study on structure/odor relationship. The
omittance of the ethano bridge of the tricyclic khusimone leads to a b
icyclic system. The stereoselective approach to this degraded structur
e is described, and the olfactory properties are studied. The key step
of the synthesis of the hydrindane nucleus is based on a highly diast
ereoselective conjugate addition to a chiral oxo-cyclopentene-2-carbox
ylate.