Hypervalent silicon heterocycles

H. H. Karsch, R. Richter, E. Witt, "Novel Sila-Phospha-Heterocycles and Hypervalent Silicon Compounds with Phosphorus Donors", in Organosilicon Chemistry III From Molecules to Materials (Eds. N. Auner, J Weis), VCH, Weinheim, 1997, p. 460. 

Novel Sila-Phospha-Heterocycles and Hypervalent Silicon Compounds with Phosphorus Donors... 

Keywords Benziodoxoles Hypervalency Hypervalent Hypervalent boron Hypervalent bromine Hypervalent heterocycles Hypervalent iodine Hypervalent silicon Hypervalent sulfur Iodine heterocycles... 

Summary The reaction of two equivalents of lithium phosphinomethanides with di- or trifunctional chlorosilanes yields novel five- and six-membered heterocycles by multistep rearrangements or transmetallation reactions. Silaethene intermediates and hypervalent intermediates are likely to be involved. The reaction of one or two equivalents of lithium phosphinomethanide Li[C(PMe2)2(SiMe2Ph)] TMEDA with pTolSiCb and ci QHbcii iCb yields novel penta- and hexacoordinated silicon complexes. Both are the first examples of truly hypervalent organosilicon species with phosphorus donors characterized by X-ray structure determination. 

Examples of stable, anionic, hypervalent lO-Si-5 silicon—oxygen heterocycles were originally reported by Martin and coworkers (1979JA1591,... 

---