Stable dicarbonylcarbene complexes of bis(oxazolinyl)pyridine ruthenium and osmium

Article abstract of DOI:10.1246/cl.1996.1071

The reaction of RuCl₂(pybox)(C₂H₄) [pybox = 2,6-bis(oxazolinyl)pyridine] 1 and OsCl₂(pybox)(propylene) 6 with dimethyl diazomalonate gave stable dicarbonylcarbene complexes 9 and 10 in 92% and 59% yields, respectively. The carbene moiety of 9 proved to be almost parallel in the Cl-Ru-Cl plane by 10-12° and perpendicular to the pybox plane by X-ray analysis. The transfer of the carbene moiety of 9 to styrene could be observed at 110°C to give the corresponding cyclopropane 15 but in a low yield (11%) with asymmetric induction in 36% ee.