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The use of 1,2-diselenolato-1,2-dicarba-closo-dodecaborane(12) dianions [1,2-(1,2-C 2 B 10 H 10 )Se 2 ] 2− prepared in situ as the dilithium salt may lead to irreproducible results. This is shown by the straightforward synthesis of silanes using the purified and isolated dianions, in contrast with previous less successful attempts. Thus, the reactions of the dianions with dichlorosilanes afford the five-membered diselenasila cycles containing the SiMe 2 or the SiPh 2 units, and with 1,2-dichloro-tetramethyldisilane the six-membered cycle containing the Si 2 Me 4 unit. The latter was studied by X-ray diffraction, and all products were characterized by multinuclear magnetic resonance ( 1 H, 13 C, 29 Si, 77 Se NMR) in solution. Novel isotope effects were detected in 13 C and 77 Se NMR spectra. Exchange reactions of the five-and six-membered diselanasila cycles with chlorosilanes were studied.

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1,1′‐Diaminoferrocene (2) and 1,1′‐bis(trimethylsilylamino)ferrocene (3) have been converted into sulfinylamines by treatment with thionyl chloride in the presence of triethylamine. In the case of 2 the 1:2 reaction affords 1,1′‐bis(sulfinylamino)ferrocene (5) and the 1:1 reaction gives 6‐amino‐1‐sulfinylaminoferrocene (6). Bis(trimethylsilylamino)ferrocene reacts with thionyl chloride in a 1:1 molar ratio to give 1‐sulfinylamino‐6‐(trimethylsilylamino)ferrocene (8). In contrast, the reaction of N,N′‐dilithiobis(trimethylsilylamino)ferrocene (4) with thionyl chloride gives the [3]ferrocenophane 9, which contains an N–S(O)–N bridge, rather than sulfinylamines or a sulfur diimide. The molecular structures of 5 and 8 were determined by X‐ray analysis. The 57Fe NMR chemical shift (δ = +2597.0 ppm) for 5 indicates the strong π‐acceptor properties of the NSO groups. Dynamic 1H and 13C NMR spectra prove the hindered rotation of the NSO group about the C–N bonds in 5, 6 and 8. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

The most efficient strategies for the synthesis of novel 1,3dichalcogeno-2-phospholanes (chalcogen E = O, S, Se, Te) are introduced, starting from 1,2-dicarba-closo-dodecaborane(12) ("ortho-carborane"), its 1,2-di-lithiated derivative, and various phosphorus halides. The annelation of the phospholane ring with the rigid three-dimensional carborane framework causes markedly different properties when compared with other phospholanes.