Silicon potassium radical anions

Dodecamethylcyclohexasilane gives a radical anion when treated with sodium-potassium alloy in dimethoxyethane-tetrahydrofuran at — 95° C (86). By ESR analysis, it was concluded that the unpaired electron is delocalized equally over all six silicon atoms and so contacts equally all of the protons on the 12 methyl groups of the molecule. Recently, similar radical anions [Si(CH3)2]5T and [Si(CH3)2]7T have been obtained from the five- and seven-membered ring cyclopolysilanes (21,205a). 

Stable ladder oligosilanes are also of interest. The potassium metal reduction of the neutral ladder oligosilanes containing 6-12 silicon atoms fully substituted by isopropyl groups leads to the formation of corresponding anion-radicals that are highly stable at room temperatnre (Kyushin et al. 2000). These silanes can be nsed as electric switchers. 

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