Ring-closing metathesis of N-alkenyl-cyanamides

An entry to new classes of nitrogen-containing heterocycles featuring both a cyanamide and an unsaturated 5-, 6- or 7-membered ring is reported. They can be readily obtained by ring-closing metathesis of the corresponding N-alkenyl-cyanamides – new partners for olefin metathesis that can be easily obtained by copper- or palladium-catalyzed alkenylation of cyanamides – using Hoveyda–Grubbs or Grubbs second generation catalysts. In addition to the potential of these novel heterocycles in drug discovery or as building blocks, the presence of the endocyclic double bond was shown to provide a useful access to novel polycyclic heterocycles.