It is classified as a metallole, i.e. an unsaturated five-membered ring containing a heteroatom.

It is a structural analog of cyclopentadiene, with tin replacing the saturated carbon atom.

[1] 1λ2-Stannole has formula C4H4Sn, with no hydrogen on the tin atom, which is in the +2 oxidation state.

[2] 1,1-Dibutylstannole is a pale yellow oil prepared from 1,4-dilithio-1,3-butadiene and dibutyltin dichloride.

[3] 1,1-Dimethyl-2,3,4,5-tetraphenyl-1H-stannole, for example, can be formed by the displacement reaction of 1,4-dilithio-1,2,3,4-tetraphenyl-1,3-butadiene and dimethyltin dichloride.