Construction of Enantioenriched [3.1.0] Bicycles via a Ruthenium-Catalyzed Asymmetric Redox Bicycloisomerization Reaction

Enantiomerically enriched [3.1.0] bicycles containing vicinal quaternary centers were synthesized from [1,6]-enynes using a cyclopentadienylruthenium catalyst containing a tethered chiral sulfoxide. The reaction was complicated by the fact that the substrates contained a racemic propargyl alcohol that could affect the selectivity of the process. Nonetheless, high levels of enantioinduction were observed, despite complications arising from the...