Facile one-pot synthesis of 2-oxazoline

DMAP catalyzed one-pot synthesis of 2-oxazolines from easily accessibly carboxylic acids and 2-chloroethyl isocyanate. During the reaction R 2 substituted carbon at position 1 of the isocyanate can keep the chirality unchanged. Microwave-assisted synthesis can further enhance the reaction yield and reduce the reaction time. The mild and facile synthesis of 2-oxazolines with diversified functionalities implied the impact of this strategy in the field of 2-oxazolines, their derivative and polymers. We developed a facile one-pot synthesis of 2-oxazolines from carboxylic acid and 2-chloroethyl isocyanate, involving amide bond formation and a following intramolecular cyclization using 4-dimethylaminopyridine as the catalyst. A large variety of functional groups are well tolerated by the mild reaction conditions to afford diverse 2-oxazolines in good to excellent yields. This reaction will keep the chirality of the isocyanate at position 1, the R 2 substituted carbon. Microwave-assisted synthesis can further enhance the reaction yield and reduce the reaction time to <5 min. This method facilities the synthesis of 2-oxazolines for diverse applications, such as 2-oxazoline derived polymers and materials.