title: Hypervalent Pentafluoroethylgermanium Compounds, [(C2F5)nGeX5-n]-and [(C2F5)3GeF3]2-(X=F, Cl; n=2-5).
abstract: This paper gives an account on hypervalent fluoro- and chloro(pentafluoroethyl)germanium compounds. The selective synthesis of the tris(pentafluoroethyl)dichlorogermanate salt [PNP][(C2F5)3GeCl2] as well as its X-ray structural analysis is described. As a representative example for pentafluoroethylfluorogermanates, the synthesis and structure of 2,4,6-triphenylpyryliumtris(pentafluoroethyl)difluorogermanate [C23H17O][(C2F5)3GeF2] is reported. Fluoride-ion affinities for pentafluoroethylgermanes were calculated using quantum chemical methods, disclosing (C2F5)3GeF as a weaker Lewis acid than (C2F5)3SiF or (C2F5)3PF2. The theoretical results were confirmed by experiments and give the basis of a synthetic protocol for (C2F5)3GeF. Pentakis(pentafluoroethyl)germanate [PPh4][Ge(C2F5)5] was detected as an intermediate during the synthesis of [PPh4][(C2F5)4GeF] starting from tris(pentafluoroethyl)difluorogermanate and LiC2F5.
authors.affiliation: Centrum für Molekulare Materialien, Fakultät für Chemie, Anorganische Chemie, Universität Bielefeld, Universitätsstraße 25, 33615, Bielefeld, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Pelzer
authors.affiliation: Centrum für Molekulare Materialien, Fakultät für Chemie, Anorganische Chemie, Universität Bielefeld, Universitätsstraße 25, 33615, Bielefeld, Germany.
authors.forename: Beate
authors.initials: B
authors.lastname: Neumann
authors.affiliation: Centrum für Molekulare Materialien, Fakultät für Chemie, Anorganische Chemie, Universität Bielefeld, Universitätsstraße 25, 33615, Bielefeld, Germany.
authors.forename: Hans-Georg
authors.initials: HG
authors.lastname: Stammler
authors.affiliation: Consultant, Merck KGaA, Frankfurter Str. 250, 64293, Darmstadt, Germany.
authors.forename: Nikolai
authors.initials: N
authors.lastname: Ignat'ev
authors.affiliation: Centrum für Molekulare Materialien, Fakultät für Chemie, Anorganische Chemie, Universität Bielefeld, Universitätsstraße 25, 33615, Bielefeld, Germany. b.hoge@uni-bielefeld.de.
authors.forename: Berthold
authors.initials: B
authors.lastname: Hoge
keywords: Lewis acids; fluoride ion affinity; fluorine; germanate; pentafluoroethyl