title: Cyclic Disilylated and Digermylated Germylenes.
abstract: The preparation of triethylphosphine adducts of cyclic disilylated or digermylated germylenes was achieved by reaction of 1,4-dipotassio-1,1,4,4-tetrakis(trimethylsilyl)tetramethyltetrasilane with GeBr2·(dioxane) and PEt3. Phosphine abstraction with B(C6F5)3allowed formation of the base-free germylenes, which undergo 1,2-trimethylsilyl shifts to the germylene atom to form the respective silagermene or digermene, which further dimerize in [2 + 2] cycloadditions to tricyclic compounds. The reasons responsible for the germylenes' completely different reactivities in comparison to the previously studied analogous stannylenes and plumbylenes were elucidated in a theoretical study.
authors.affiliation: Institut für Anorganische Chemie, Technische Universität Graz , Stremayrgasse 9, A-8010 Graz, Austria.
authors.forename: Johann
authors.initials: J
authors.lastname: Hlina
authors.forename: Judith
authors.initials: J
authors.lastname: Baumgartner
authors.forename: Christoph
authors.initials: C
authors.lastname: Marschner
authors.forename: Lena
authors.initials: L
authors.lastname: Albers
authors.forename: Thomas
authors.initials: T
authors.lastname: Müller