Defluorosilylation of trifluoromethane: upgrading an environmentally damaging fluorocarbon

Abstract

The rapid, room-temperature defluorosilylation of trifluoromethane, a highly potent greenhouse gas, has been achieved using a simple silyl lithium reagent.

Silylboronate-Mediated Defluorosilylation of Aryl Fluorides with or without Ni-Catalyst

“…A highly nucleophilic, silyl anionic species directly reacts with alkyl fluorides via a concerted S N 2 process ( Scheme 1B ). The defluorosilylation reaction was then successfully reported by several groups ( Gao et al, 2019 ; Liu et al, 2019 ; Kojima et al, 2019 ; Mallick et al, 2019 ; Coates et al, 2019 ; Lim et al, 2020 ; Sheldon et al, 2020 ). In 2019, Martin and co-workers reported the lithium-promoted defluorosilylation of organic fluorides, in which lithium bis(trimethylsilyl)amide (LiHMDS) and dimethyl ether (DME) cooperated well to activate the inert C–F bond ( Scheme 1C ); ( Liu et al, 2019 ).…”

Repurposing of F-gases: challenges and opportunities in fluorine chemistry

“… 183 Greater access to easy-to-use fluorinated transfer agents often leads to an increased use of those fluorinated moieties in pharmaceutical design. 179 …”

“…178 In 2020, our group reported the rapid, room-temperature defluorosilylation of CF 3 H with the silyl lithium reagent 1 (Scheme 2d). 179 The reaction forms a valuable difluoromethyl organosilicon building block, 2, which is closely related to Me 3 Si-CF 2 H, both are known difluoromethyl transfer agents. 180,181 The reaction was successfully scaled up to synthesise 2 on a gram-scale in a 68% isolated yield.…”

Bipyridinium and Phenanthrolinium Dications for Metal‐Free Hydrodefluorination: Distinctive Carbon‐Based Reactivity

“…Since then, cationic aluminum [13] and germanium [14] systems have been used as initiators for the catalytic HDF of fluoroalkanes. Further, HDF has been reported using cationic lithium, [15] silicon [16] and phosphorus [17] centers.…”