The reactions of bridged tris(trimethylsilyl)silyl fragments with 2 molar equiv of potassium tert-butoxide allow the generation of R,ω-oligosilyl dianions (1a, 2a, 3a, 4a). Depending on the nature of the spacer between the oligosilyl units, these compounds can be used to generate either linear or cyclic derivatives. They are especially attractive for the formation of homoand heterocyclosilanes, as exemplified by the synthesis of sila-, stanna-, and zirconocenacyclosilanes. A linear bis(potassiumsilyl)acetylene (4a) was used to bridge two zirconocene units, (Cp 2 Zr(Cl)Si(SiMe 3 ) 2 CCSi(SiMe 3 ) 2 Zr(Cl)Cp 2 ) (11).

Synthesis, properties, and reactions of various alkynyl oligosilanes, and their potassium derivatives are described. A series of tris(trimethylsilyl)silylalkynes have been prepared. Their reaction with potassium tert‐butoxide leads to the corresponding potassium derivatives, which can be subjected to further derivatization. X‐ray structures of three oligosilylalkynes are reported. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

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(4-Methyl-pyridin-2-yl)(trimethylsilanyl)amine (ApSi-H) and tert-butyl(4-methyl-pyridin-2-yl)amine (AptBu-H) were synthesized via salt metathesis and aryl amination reactions, respectively. Lithiation of these two aminopyridines using n-BuLi and the reactions with [(dme)NiCl2] (dme = dimethoxyethane) or [(cod)PdCl2] (cod = cyclooctadiene) in THF at low temperature gave rise--after workup in hexane--to group 10 amido compounds, [(ApSi)4Ni2], [(AptBu)2Pd], [(AptBu-H)(AptBu)2Ni], [(AptBu)3(C2H5O)3Ni3OLi(thf)], and [(AptBu)2Ni(tBupy)2] (tBupy = 4-tert-butylpyridine). The aminopyridinato complexes were characterized by X-ray crystal structure analysis. The highly strained binding situation of the aminopyridinato ligands suggested that these compounds might be efficiently converted into catalytically active species. The applications of some of the synthesized complexes as Suzuki cross-coupling catalysts (activation of aryl chlorides) are described and [(ApSi)4Ni2] is a rare example of a "phosphine-free" catalyst system. A number of late transition metal complexes were found to successfully catalyze polymerization of MeH2SiSiH2Me toward soluble, linear poly(methylsilane). Remarkable activity was observed for [(ApSi)2Pd].