Cyclisation reactions of dienyl-and enynylsilanes by carbon–carbon bond formation under RCM conditions yield five-, six-and seven-membered silacycloalkenes. The relative ease of ring formation from dienes was in the order six-> seven-> five-membered rings. A conjugated vinylsilacyclopentene was formed from the corresponding enyne substrate. Silaspirenes have been prepared from silacarbacycles by the same methodology. ...
