Butyl lithium (nBuLi)-mediated carboxylation of vinylidenecyclopropanes with CO2

A novel butyl lithium (nBuLi)-mediated carboxylation of vinylidenecyclopropanes with CO2 in THF at −78 °C followed by the further transformation has been realized to afford the corresponding carboxylic adducts in moderate to good yields under normal conditions. The scope and limitations as well as the plausible reaction mechanism have been also discussed in this paper.