Conversion of Carbon Dioxide into Oxazolidinones Mediated by Quaternary Ammonium Salts and DBU

Abstract A straightforward method to construct oxazolidinones through a three‐component reaction involving CO 2 , epoxides, and amines promoted by a combination of Bu 4 NI and 1,8‐diazabicyclo[5.4.0]undec‐7‐ene was developed. A wide range of aromatic and aliphatic amines and monosubstituted epoxides were converted into 3,5‐disubstituted‐2‐oxazolidines in up to 95 % yield. This metal‐free and easily available catalytic system was applicable to a broad range of substrates, including conventionally challenging ones such as aliphatic epoxides, at atmospheric pressure. Preliminary mechanistic studies suggested a reaction pathway involving β‐amino alcohols.