Adducts formed between some halogenosilanes and the organic bases pyridine, trimethylamine, and tetramethylethylenediamine. Part I. Stoichiometry
Pyridine causes SiH3F, SiH3Cl, SiH2F2, and some silyl pseudohalides to decompose. With each of the other halides of formula SiH4–nXn it forms a single adduct, of 1 : 2 (halide : base) composition in most cases, though SiH2Br2, SiH2I2, SiHBr3, and SiHI3, like SiI4, give 1 : 4 adducts. Trimethylamine forms two adducts with most halogenosilanes, one of which is always of 1 : 1 composition, while tetramethylethylenediamine forms 1 : 1 adducts with the fluorosilanes, the chlorosilanes, and bromosilane. Methylation at silicon reduces the acceptor properties of the silicon atom.