[3,3]-Sigmatropic Rearrangement of Cyclopropenylcarbinyl Cyanates: Access to Alkylidene(aminocyclopropane) Derivatives.

Cyclopropenylcarbinyl cyanates, generated in situ by dehydration of the corresponding carbamates, underwent an efficient and stereoselective [3,3]-sigmatropic rearrangement leading to the corresponding alkylidene(isocyanatocyclopropanes), which could be converted into various alkylidene(aminocyclopropane) derivatives in a one-pot manner. This transformation complements the repertoire of sigmatropic rearrangements involving cyclopropenylcarbinol derivatives and in particular, the previously reported Overman rearrangement of cyclopropenylcarbinyl trichloroacetimidates.