Methylenespiro[2.3]hexanes via Nickel-Catalyzed Cyclopropanations with [1.1.1]Propellane
Songjie Yu, Adam Noble, Robin B. Bedford* and Varinder K. Aggarwal*
*School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K., Email: r.bedfordbristol.ac.uk, v.aggarwalbristol.ac.uk
S. Yu, A. Noble, R. B. Bedford, V. K. Aggarwal, J. Am. Chem. Soc., 2019, 141, 20325-20334.
DOI: 10.1021/jacs.9b10689 (free Supporting Information)
see article for more reactions
Nickel(0) catalysis enables the use of [1.1.1]propellane as a carbene precursor in cyclopropanations of a range of functionalized alkenes to give methylenespiro[2.3]hexane products. Computational studies provide support for initial formation of a Ni(0)-[1.1.1]propellane complex followed by concerted double C-C bond activation to give the key 3-methylenecyclobutylidene-nickel intermediate.
see article for more examples
proposed concerted C-C bond activation (retro-cyclopropanation)