Enantioselective Synthesis of the Functionalized Bicyclo[2.2.1]heptane Derivatives, Key Intermediates for the Chiral Synthesis of Santalenes and Santalols
Optically active functionalized bicyclo[2.2.1] heptane derivatives obtained by the asymmetric Diels–Alder cycloaddition of ethyl p-tolylsulfinylmethylenepropionate with cyclopentadiene provide the potentially useful intermediates for synthesis of bicyclic sesquiterpenes such as (+)-epi-β-santalene.