ChemInform Abstract: Fluorosilyl(pyrrolyl)silylamines as Precursors for Intra- and Intermolecularly Stabilized Iminosilanes

Three indolyl- and pyrrolylsilylamines 1–3 were prepared from lithiated heterocyclics and fluorosilylamines. Further reaction with di- tert -butyldifluorosilane led to the fluorosilylpyrrolylsilylamines 4 and 5 . The fluorosilylpyrrolylsilylamine 6 was prepared by reaction of bis(fluorodiisopropylsilyl)amine and lithium pyrrolide. Lithiiation with n-butyllithium of 4–6 solved in THF gave the iminosilane-LiF adducts 7–9 ; in contrast, lithiation of 5 in n-hexane led to the lithium fluorosilylamid 10 . Heating of the iminosilane-LiF adduct 7 gave the bicyclic system 11 , an intramolecularly stabilized iminosilane. Addition of chlorotrimethylsilane to 9 led to fluorine-chlorine exchange and elimination of lithium chloride. The product is the intermolecular stabilization of the intermediate iminosilane as a four-membered ring 12 . The X-ray structures of 1, 11 and 12 have been determined.