Abstract An efficient one‐pot general method for the high‐yield synthesis in solution of oxazolidinones and oxazinones from allyl‐ and homoallylamines, respectively, has been developed. The reaction is carried out at an atmospheric pressure between 0°C and room temperature using a solution of carbon dioxide in acetonitrile and hindered guanidine as the base.
A cyclizative atmospheric CO2 fixation by unsaturated amines such as allyl and propargylamines under mild reaction conditions, efficiently leading to cyclic carbamates bearing a iodomethyl group, have been developed utilizing tert-butyl hypoiodite (t-BuOI).