Synthesis, structure and a nucleophilic coordination reaction of Germanetelturones

beta-Diketiminato cyclopentadienyl and ferrocenylethynyl germylenes LGeR (L = HC[C(Me)N-2,6-iPr(2)C(6)H(3)](2), R = Cp (1) and C equivalent to CFc (2)) were prepared and utilized to synthesize the Ge=Te bond species. Reactions of 1, 2, and LGeC equivalent to CPh (3) with an excess of Te powder proceeded in toluene under reflux successfully yielded germanetellurone L(R)GeTe (R = Cp (4), C equivalent to CFc (5), and C equivalent to CPh (6)). Further reaction of 4 with GeCl2.dioxane at -78 degrees C resulted in L(Cp)GeTe(GeCl2) (7), the first example of a germylene germanetellurone adduct. Both compounds 4 and 7 contain two isomers that are generated by the simultaneous 1,2-H- and 1,3-H-shifts over the Cp ring at the Ge atom. The reactions of L(Me)GeE with AuC6F5 center dot SC4H8 at room temperature led to pentafluorophenyl gold(i) germanethione and germaneselone compounds L(Me)GeE(AuC6F5) (E = S (8) and Se (9)). The formation of compounds 7-9 exhibits a rare nucleophilic coordination reaction pathway by the Ge=E (E = S, Se, Te) bond towards the metal-containing Lewis acidic species. The structures of compounds 1, 2, and 4-9 are studied by the NMR and/or IR spectroscopy and X-ray crystallography.