Chemistry Letters, Vol.39, No.7, 702-703, 2010
Cyclopropanation of Olefins with Diazo Compounds Catalyzed by a Dicopper-substituted Silicotungstate [gamma-H2SiW10O36Cu2(mu-1,1-N-3)(2)](4-)
The dicopper-substituted gamma-Keggin silicotungstate (TBA)(4)[gamma-H2SiW10O36Cu2II(mu-1,1-N-3)(2)] (I, TBA = tetra-n-butylammonium) could act as an efficient precatalyst for the chemoselective cylopropanation of olefins with diazo compounds. Various kinds of olefins were efficiently converted to the corresponding cyclopropane derivatives in good yields.