Interaction of diazoalkanes with unsaturated compounds. 12. Stereochemistry of cyclopropanation of norbornenes with diazomethane in the presence of transition metal complexes

Article abstract of DOI:10.1007/BF00704005

The stereochemistry of cyclopropanation of norbornenes with diazomethane in the presence of Cu, Pd, and Rh compounds has been studied.Stereoselectivity of the cyclopropanation depends on the nature of the transition metal and does not depend on its valent state or ligand environment.The reaction proceeds predominantly as exo-cycloaddition of the methylene fragment.The greatest amount of endo-isomer (up to 47 percent) is formed in cyclopropanation of norbornadiene and exo-tricyclo<3.2.1.0^2,4>oct-6-ene in the presence of Cu and Rh compounds.