title: Synthesis of tris- and tetrakis(pentafluoroethyl)silanes.
abstract: The synthesis and complete characterization of functional, highly Lewis acidic tris(pentafluoroethyl)silanes as well as tetrakis(perfluoroalkyl)silanes Si(C2F5)4 and Si(C2F5)3 CF3 by direct fluorination is described. The reaction of SiCl4 with LiC2F5 invariably affords (pentafluoroethyl)fluorosilicates. To avoid silicate formation by fluoride transfer from LiC2F5 the Lewis acidity of the silane has to be decreased by electron-donating substituents, such as dialkylamino groups. The easily accessible Si(C2F5)3 NEt2 is a valuable precursor for a series of tris(pentafluoroethyl)silanes.
authors.affiliation: Fakultät für Chemie, Universität Bielefeld, Universitätsstrasse 25, 33615 Bielefeld (Germany).
authors.forename: Simon
authors.initials: S
authors.lastname: Steinhauer
authors.forename: Julia
authors.initials: J
authors.lastname: Bader
authors.forename: Hans-Georg
authors.initials: HG
authors.lastname: Stammler
authors.forename: Nikolai
authors.initials: N
authors.lastname: Ignat'ev
authors.forename: Berthold
authors.initials: B
authors.lastname: Hoge
mesh_terms: D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D012821:Silanes / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D012821:Silanes
keywords: Lewis acids; direct fluorination; fluorine; silanes