Organosilicon chemistry. Part 25. Catalysis of the reaction between alcohols and silanes by hydrido-, dinitrogen-, and ethylene-iron complexes

Abstract

The reaction between alcohols, ROH (R = Me, Et, Prⁿ, or Buⁿ), and SiH(OEt)₃ or SiPh₂H₂ is strongly catalysed at room temperature by [FeH₂(PMePh₂)₄] or by [FeH₂(N₂)(PEtPh₂)₃]. With SiH(OEt)₃, reaction is complicated by alkoxy-exchange when R ≠ OEt. With both catalysts the reactions have induction periods but are thereafter first order in the concentration of each of the reactants and of the catalyst. Mechanisms are proposed based on the formation of iron–silyl complexes. The complex [Fe(C₂H₄)(dppe)₂](dppe = Ph₂PCH₂CH₂PPh₂) also catalyses the reaction but is rapidly deactivated by conversion into [FeH₂(dppe)₂].