Asymmetric Intermolecular Cobalt-Catalyzed Pauson-Khand Reaction Using a P-Stereogenic Bis-phosphane

The asymmetric intermolecular and catalytic PausonKhand reaction has remained an elusive goal since Khand and Pauson discovered this transformation. Using a novel family of P-stereogenic phosphanes, we developed the first catalytic system with useful levels of enantioselection for the reaction of norbornadiene and trimethylsilylacetylene. The results demonstrate that Cobisphosphane systems are sufficiently reactive and that they lead to high selectivity in the intermolecular process.