Complexes of decamethylsilicocene: Cp2*Si(CO) and Cp2*Si(N2)

The synthesis and IR spectroscopic detection of the monocarbonyl and mononitrogen complex of decamethylsilicocen in liquid xenon (LXe) and liquid nitrogen (LN₂) is reported. The reactions were found to be highly incomplete under a few bar of CO or N₂ and reversibel when the pressure is released. Cp₂*Si(CO) is characterized by three isotopomeres and Cp₂*Si(N₂) was synthesized on two independent routes.     

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On the reactions of alkylsulfonyl and perfluoroalkylsulfonyl fluorides with hydroxylamines and hydrazines

Sulfonic acid chlorides react with hydroxylamine to form predominantly N-substituted products [1].Sulfonic acid fluorides react with hydroxylamine by formation of N-mesylhydroxylamine, hydrazinium(1+) and hydroxylammonium mesylate [2]. R_fSO₂F (R_f = C₄F₉, C₈F₁₇) reacting in the same way as CH₃SO₂F [3], the latter is considered to be a model compound for this kind of reactions.

The formation of the hydrazinium salt is explained by the occurrence of O-mesylhydroxylamine as intermediate. We conclude from the yields that sulfonic acid fluorides react with hydroxylamine to form predominantly O-substituted products.In order to prepare this O-derivative the reaction between O-(trimethylsilyl)hydroxylamine and mesylfluoride was carried out. Hydrazinium mesylate could be isolated also, which indicates the formation of the instable O-derivative.The reactions of methylhydrazines and silylated hydrazines with mesylfluoride lead to mesylated products as expected.     

Fabrication of Anodic Aluminum Oxide Templates with Small Interpore Distances

The influence of the electropolishing and anodization voltage on surface morphology has been carefully studied for fabrication of ordered anodic aluminum oxide （AAO） templates. In accordance with that in the anodization experiment, the size of small patterns on the foil surface formed from the electropolishing treatment increases with voltage. Using a combined method of small-voltage eleetropolishing and anodization, we have fabricated well ordered templates with much smaller interpore distances compared with that under normal-voltage fabrication conditions. The Ni nanowire arrays with two small diameters are eleetrodeposited through the above templates, exhibiting different magnetic properties. This also helps us to clarify the inner structure of this kind of templates.     

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