Tandem Olefin Metathesis/Oxidative Cyclization: Synthesis of Tetrahydrofuran Diols from Simple Olefins

A tandem
olefin metathesis/oxidative cyclization has been developed
to synthesize 2,5-disubstituted tetrahydrofuran (THF) diols in a stereocontrolled
fashion from simple olefin precursors. The ruthenium metathesis catalyst
is converted into an oxidation catalyst in the second step and is
thus responsible for both catalytic steps. The stereochemistry of
the 1,5-diene intermediate can be controlled through the choice of
catalyst and the type of metathesis conducted. This olefin stereochemistry
then controls the THF diol stereochemistry through a highly stereospecific
oxidative cyclization.