Reactions of strained organosilicon heterocycles with nonacarbonyldi-iron(0). Part 2. Preparation and reactions of silaferracyclopentanes

Abstract

The formation of silaferracyclopentanes, by the reaction of silacyclobutanes with iron carbonyls, is described and their properties and reactions are discussed. The parent complex, 2,2,2,2-tetracarbonyl-1,1 -dimethyl-1 -sila-2- ferracyclopentane, has been prepared by the reaction of Me₂[graphic omitted]CH₂ with [Fe(CO)₉](the preferred route) or, under u.v. irradiation, with [Fe(CO)₅] or [Fe₃(CO)₁₂]; it has also been synthesised from Na₂[Fe(CO)₄] and SiMe₂(CH₂CH₂CH₂Cl)Cl. Analogues having aryl, alkoxy-, or chloro-substituents at silicon are described, together with derivatives of 1,1,3,3-tetramethyl-1,3-disilacyclobutane and two silabenzocyclobutenes. Infrared, ¹H and ¹³C n.m.r., and mass spectroscopic data are discussed. Chemical properties of the silaferracyclopentanes are contrasted with those of the parent silacyclobutanes. The complex [graphic omitted]SiMe₂)(CO)₄] shows some activity as a hydrosilylation catalyst.