Poly (germanium thiolate): A new class of organometallic polymers having a germanium-sulfur bond in the main chain

A novel germanium-containing copolymer 3a having a germanium(IV) unit and a trimethylene sulfide unit alternatingly in the main chain was prepared by the combined use of a germylene, 1,3-bis(trimethylsilyl)-1,3-diaza-2-germa(II)-indan (1a) and thietane (2). The resulting copolymer has a very high molecular weight (M̄_w > 10⁶). The usage of a germylene, bis[bis(trimethylsilyl)aminato]germanium(II) (1b), as a comonomer also gave an alternating copolymer 3b with high molecular weight in good yields. On the other hand, the reaction of a germylene, bis(N-trimethylsilyl-tert-butylaminato)germanium(II) (c), with thietane afforded a 1:1 adduct 4c having a 1-thia-2-germacyclopentane structure without producing an alternating copolymer.