Dinuclear organogermanium chalcogenide complexes as intermediates towards functionalized clusters

Abstract

Reactions of R¹GeCl₃ (R¹ = CMe₂CH₂COMe) with (Me₃Si)₂E (E = S, Se, Te) yield three new organogermanium chalcogenide complexes [(R¹GeCl)₂S₂] (1), [(R¹GeCl)₂Se₂] (2), and [(R¹GeCl)₂Te₂] (3) with functionalized ligands R¹ = CMe₂CH₂COMe. NMR titration experiments clearly demonstrate that these dimeric complexes are intermediates in the formation of the well-known sesquichalcogenide clusters [(R¹Ge)₄E₆]. In striking contrast to related tin compounds that were recently reported, the mono-bridged complexes of the type “[(R¹GeCl₂)₂E]” and defect-heterocubane-type clusters “[(R¹Ge)₃E₄Cl]” do not form on the NMR time scale for E = S or Te, and only in traces for E = Se.