DBU-Mediated Carboxylative Coupling of Primary Amines, Carbon Dioxide and Propargyl Chlorides

A carboxylative coupling reaction of various primary amine and 3-phenyl-2-propynyl or 2-nonynyl chloride in the presence of 8-diazabicyclo[5.4.0]undec-7-ene (DBU) using carbon dioxide as carboxylative reagent was presented. This transition-metal free reaction system shows broad substrate scope and gives a series of propargylcarbamates in moderate to good yield. The obtained N-alkyl substituted carbamate product can undergo base-catalyzed intramolecular cyclization reaction to afford functionalized 4-methylene-2-oxazolidinone in good yield.