Abstract The first synthesis of a monomeric C-unsubstituted silole is described. Photo- oxygenation of 1, 1-dimethyl-1-silacyclopent-3-ene leads to an allylic hydroperoxide with a shifted carobon—carbon double bond (ene reaction) which, upon treatment with a reducing agent (NaBH 4) gives 1, 1-dimethyl-1-silacyclopent-4-ene-3-ol. Catalytic vacuum-flow dehydration of this alcohol gives monomeric 1, 1-dimethylsilole, which is characterized by ...