Development of [CpRu(η 6 -benzylcarbamate)]X salts as two-stage photobase generators

Silylimidazolium Hexafluorophosphate Salts as Synthetic Precursors to N-Heterocyclic Carbene Pentafluorophosphorus Adducts

“…(KPF 6 ) = 460 °C) suggested to us that Lewis acidic cations could facilitate defluorination of PF 6 – at lower temperatures. Inspired by prior work in which PF 6 – decomposition was observed in the presence of electrophilic silanes (Figure a), − we envisaged that the Si-centers of silylimidazolium cations 3 may be sufficiently Lewis acidic to elicit defluorinative decomposition of PF 6 – to PF 5 (Figure b). Desilylation of a 2-silylimidazolium would deliver the requisite NHC 4 and PF 5 , similar to the mechanism proposed by Borzov, but with a comparatively inert fluorosilane as the byproduct, rather than HF.…”