Alkali metal reduction of crown ether encapsulated alkali metal cations

Abstract

[{SiN^Dipp}BeClM]₂ ({SiN^Dipp} = {CH₂SiMe₂N(Dipp)}₂; M = Li, Na, K, Rb) are converted to ionic species by treatment with a crown ether. Whereas the lithium derivative reacts with Na or K to provide [{SiN^Dipp}BeCl]⁻[M(12-cr-4)₂]⁺ (M = Na, K), the resultant sodium species is resistant to reduction by potassium. These observations are rationalised by a hybrid experimental/theoretical analysis.