A Parisian Vision of the Chemistry of Hypercoordinated Silicon Derivatives

Abstract

Less than ten years of acquaintance with hypercoordinated silicon derivatives in our lab is described in this account. Martin's spirosilane derivatives open new opportunities as ligands and as agents for the activation of small molecules and bis‐catecholato silicates have proven to be exquisite radical precursors in photoredox conditions for broad synthetic applications.

Nickel-catalysed SET-reduction-based access to functionalized allenes via 1,4-carbohydrogenation of 1,3-enynes with alkyl bromides

“…13 Inspired by the photoredox-catalysed reactions between 1,3-enynes and alkyl silicates, we envision that a nickel-catalysed reductive RPC would be feasible for the preparation of allenes. In contrast to the oxidative generation of radicals with alkyl silicates as the radical precursors using photoredox catalysis, 14 alkyl radicals are generated from alkyl halides via the nickel-catalysed reductive pathway in the presence of an exogenous reductant. 15 Of note, alkyl halides are easily available, low cost, and structurally diverse radical precursors.…”

Bis(catecholato)silicates: Synthesis and Structural Data

“…Recently, the use of Martin's spirosilane (bearing the dianion of hexafluorocumyl alcohol) has emerged as an interesting solution to activate molecules or to deliver new transferable moieties in a practical way. [74] Thus, it is expected that other hypercoordinated silicon species will find their place and become a tool for increasing structural diversity in applied organic chemistry. We hope that this review will facilitate the knowledge of these derivatives and stimulate their research and applications in contemporary synthetic chemistry.…”

“…Future research should focus on the tuning of the silicon ligand. Recently, the use of Martin′s spirosilane (bearing the dianion of hexafluorocumyl alcohol) has emerged as an interesting solution to activate molecules or to deliver new transferable moieties in a practical way [74] . Thus, it is expected that other hypercoordinated silicon species will find their place and become a tool for increasing structural diversity in applied organic chemistry.…”

Synthesis and Reactivity of Martin’s Spirosilane-Derived Chloromethylsilicate

“…They can be prepared either by the addition of a nucleophile to Lewis acidic spirosilane 1 or by addition of the dilithio derivative of hexafluorocumyl alcohol to a trichlorosilane in the case of the methyl- and phenylsilicate [ 13 ]. In recent years, our group has been interested in the synthesis of pentacoordinate silicon derivatives [ 14 ] based on Martin’s ligands in the context of Frustrated Lewis Pair chemistry, which led to new organometallic species [ 15 , 16 , 17 ]. In the present study, we wish to report the first synthesis of chloromethylsilicate 2 that can be obtained from Martin’s spirosilane 1 and its reactivity in the presence of strong nucleophiles, a Lewis acid and a Lewis base ( Figure 1 ).…”