SYNTHESIS AND ISOMERISM OF MONOFUNCTIONAL ARYLATED CYCLOTETRASILANES

By the introduction of the novel educt traphenyl-1,2,3,4-tetra-para-to lylcyclotetrasilane (2), which shows significantly higher solubility a nd reactivity than octaphenyl-cyclotetrasilane, the first selective mo nofunctionalization of a perarylated cyclotetrasilane was achieved. Co mpound 2 was synthesized by ring closure of phenyl-para-tolyldichloros ilane with lithium. The cyclotetrasilanes Si(4)Ph(4)-p-Tol(3)X with X = OSO2CF3, F, Cl, Br, I, H or t-Bu were prepared by dearylation of 2 w ith trifluoromethanesulfonic acid and subsequent reaction with lithium or potassium halides, sodium boranate, and tert-butyllithium, respect ively. The compounds were isolated in high yield and purity. They were characterized by H-1, C-13, F-19, and Si-29 NMR spectroscopy.