title: Lewis acidity of Si6Cl12 and its role as convenient SiCl2 source.
abstract: The free cyclohexasilane Si6Cl12 (1) was obtained in 66% yield from the corresponding Cl(-) diadduct [nBu4N]2[1·2Cl] and AlCl3 in C6H6. The substituted cyclohexasilane 1,1-(Cl3Si)2Si6Cl10 (2), however, cannot be liberated from [nBu4N]2[2·2Cl] under comparable reaction conditions. Instead, a mixture of several products was obtained, from which the oligosilane Si19Cl36 (3) crystallized in low yields. X-ray crystallography revealed 3 to consist of two Si5 rings, bridged by one silicon atom. Compound 1 possesses Lewis acidic sites above and below the ring centroid. Competition experiments reveal that their corresponding acid strengths are comparable to that of BCl3. The reaction of 1 with 6 equiv of 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (Idipp) leads to a complete breakdown of the cyclic scaffold and furnishes the dichlorosilylene adduct Idipp-SiCl2.
authors.affiliation: Institut für Anorganische Chemie, Goethe-Universität Frankfurt am Main , Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Tillmann
authors.affiliation: Institut für Anorganische Chemie, Goethe-Universität Frankfurt am Main , Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany.
authors.forename: Maximilian
authors.initials: M
authors.lastname: Moxter
authors.affiliation: Institut für Anorganische Chemie, Goethe-Universität Frankfurt am Main , Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Bolte
authors.affiliation: Institut für Anorganische Chemie, Goethe-Universität Frankfurt am Main , Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany.
authors.forename: Hans-Wolfram
authors.initials: HW
authors.lastname: Lerner
authors.affiliation: Institut für Anorganische Chemie, Goethe-Universität Frankfurt am Main , Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Wagner