Me₃SiSiMe₂(O^<i>n</i>Bu): a disilane reagent for the synthesis of diverse silacycles <i>via</i> Brook- and retro-Brook-type rearrangement

Abstract

Herein, a readily available disilane Me₃SiSiMe₂(O ^<i>n</i> Bu) has been developed for the synthesis of diverse silacycles <i>via</i> Brook- and retro-Brook-type rearrangement. This protocol enables the incorporation of a silylene into different starting materials, including acrylamides, alkene-tethered 2-(2-iodophenyl)-1<i>H</i>-indoles, and 2-iodobiaryls, <i>via</i> the cleavage of Si-Si, Si-C, and Si-O bonds, leading to the formation of spirobenzosiloles, fused benzosiloles, and π-conjugated dibenzosiloles in moderate to good yields. Preliminary mechanistic studies indicate that this transformation is realized by successive palladium-catalyzed bis-silylation and Brook- and retro-Brook-type rearrangement of silane-tethered silanols.