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 region-and chemoselective fashion. The umpolung α-selective silylation leading to dioxasilolanes is opposed to contemporary β-selective C-C functionalization protocols of cyclopropanols. Lewis base activation of dioxasilolanes as α-silyl carbinol equivalents undergoes the unconventional [1,2]-Brook rearrangement to form tertiary alcohols. Notably, mechanistic studies indicate that an electrophilic metal-π interaction harnessing highly fluorinated ${\text{Tp}}^{{{\text{(CF}}_{\text{3}}\text{)}}_{\text{2}}}\text{Rh(nbd)}$ catalyst permitted a low-temperature C-C activation.