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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)₃ allowed 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.

SUBMITTER: Hlina J

PROVIDER: S-EPMC3714166 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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Cyclic Disilylated and Digermylated Germylenes.

Hlina Johann J Baumgartner Judith J Marschner Christoph C Albers Lena L Müller Thomas T

Organometallics 20130529 11

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)3 allowed 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 ...[more]

PMID: 23874054

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Basic Reactivity Pattern of a Cyclic Disilylated Germylene.

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