Umpolung α-Silylation of Cyclopropyl Acetates via Low-Temperature Catalytic C-C Activation

We report a redox-neutral, catalytic C-C activation of cyclopropyl acetates to produce silicon containing five-membered heterocycles in a highly regio- and chemoselective fashion. The umpolung alpha-selective silylation leading to dioxasilolanes is opposed to contemporary beta-selective C-C functionalization protocols of cyclo-propanols. Lewis base activation of dioxasilolanes as alpha-silyl carbinol equivalents undergoes the unconventional [1,2]-Brook rearrangement to form tertiary alcohols. Notably, mechanistic studies indicate that an electrophilic metal-pi interaction harnessing highly fluorinated Tp((CF3)2)Rh(nbd) catalyst permitted a low-temperature C-C activation.