Study on Silenes With Reference to Their Properties |
Inone study a disilene is prepared by an intramolecular coupling of a1,1-dibromosilane with potassium graphite. The silicon double bond in theresulting compound has a bond length of 227 picometer (second largest everfound) with trans-bent angles 33° and 31° (by X-ray diffraction). Inaddition to this the substituents around the Si-Si bond are twisted by 43°. Thedisilene isomerizes to a tetracyclic compound by heating at 110°C in xylenethereby releasing its strain energy. Siloles,also called silacyclopentadienes,are members of a larger class of compounds called metalloles. They are thesilicon analogs of cyclopentadienes and are of current academic interest due totheir electroluminescence and other electronic properties. Siloles areefficient in electron transport. They owe their low lying LUMO to a favorableinteraction between the antibonding sigma silicon orbital with an antibondingpi orbital of the butadiene fragment.