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. (C) 2022 Elsevier Ltd. All rights reserved.
Key words
2-Oxazoline/One-pot synthesis/Microwave-assisted synthesis/Isocyanate/Retention of configuration/MICROWAVE-ASSISTED SYNTHESIS/CARBOXYLIC-ACIDS/POLY(2-OXAZOLINE) HYDROGELS/OXAZOLINES/2-ARYL-2-OXAZOLINES/TRANSITION/SURFACES/ESTERS
NSTL
Elsevier