Asymmetric Total Synthesis of (−)-Vinigrol

A new strategy was
developed for the asymmetric total synthesis
of (−)-vinigrol. The strategy involved a linear sequence of
15 steps from 3-methyl-butanal (14 steps from chloro-dihydrocarvone)
and did not need protecting groups. The synthetically challenging
1,5-butano­decahydro­naphthalene core was constructed efficiently
via a type II intra­molecular [5+2] cycloaddition, followed by
a unique ring-contraction cascade.