Progress in the Halogenation of Organic Silicon Compounds

The Review deals mainly with the direct halogenation of organic silicon compounds by halogens and halogenated compounds as among the most important methods for the preparation of organosilicon compounds containing halogen in the organic radicals. With respect to preparative possibilities, experimental simplicity, and in individual cases the yields obtained, the direct chlorination and bromination of organic silicon compounds has no equal. The preparation of halogenated alkyl (and aryl) silanes by various methods has been partly covered in previous monographs and reviews1–8, but the direct halogenation of organic halogenosilanes has not yet been adequately reported in the review literature. The present paper makes an attempt to fill this gap. It gives a detailed discussion of the conditions and the mechanisms of radical halogenation (mainly with chlorination as example) under the influence of various initiators (ultraviolet radiation, peroxides, azo-compounds, γ-rays) and also electrophilic substitution and cleavage of the silicon–carbon bond in aryl- and alkylaryl-chlorosilanes. Besides substitutive halogenation, involving replacement of hydrogen in organic radicals by halogen atoms, the addition of halogen at double bonds present in these radicals is also surveyed. A list of 335 references is included.