Tandem metathesis- dihydroxylation and metathesis- oxidative cyclization reactions

Tandem catalysis provides an opportunity to assemble significant mol. complexity via mechanistically distinct reactions with a single catalyst. We have developed a tandem Z- selective cross metathesis - dihydroxylation, and have explored the substrate specificity of the catalytic system. We have also developed a tandem metathesis - oxidative cyclization to assemble THF diol motifs. Due to the stereospecificity of the oxidn. step, the product stereochem. is detd. in part by the olefin geometry. The stereochem. of the olefin in turn is detd. by the type of metathesis performed and choice of catalyst. The reaction scope and applications of the oxidative cyclization will be explored. Mechanistic comparisons between dihydroxylation and oxidative cyclization will also be discussed, specifically with regards to the nature of the ruthenate ester hydrolysis step