EXTRAORDINARY REACTIVITY OF RING SI-C BONDS IN 1,1-DIMETHYL-TRANS-2,3-BIS(2',2'-DIMETHYLCYCLOPROPYLIDENE)-1-SILACYCLOPROPANE

The reactions of the title silirane with oxygen, water, alcohols, primary and some secondary amines, hydrogen sulfide, carboxylic acids and hydrazoic acid proceeded exothermally at room temperature with opening of the SiC bond of the SiC2 ring. Hydrogen chloride reacted rapidly at -78°C, as did methyl- and phenyl-lithium and lithium dialkylamides. Ring cleavage of the silirane also could be effected with acetyl chloride, boron trichloride and lithium aluminum hydride. A comparison of the reactivity of the title silirane with that of 1,1-dimethyl-1-silacyclobutane shows the dramatic effect of the high ring strain in the former, which results in hyper-reactive ring SiC bonds. © 1978.