A-methylene carbamates

It is worth mentioning the synthesis of cyclic a-methylene carbamates, which were also produced via Markovnikov intramolecular nucleophilic addition of O-car-bamates, generated in situ from a propargylic amine and CO2, in the presence of Ru(cod) (cot)/phosphine as catalyst precursor (cod cyclooctadiene cot cycloocta-triene) (Scheme 8.23) [75]. 

---