Potassium Hydroxide → 5-(Chloromethyl)-1,2-oxazole-3-carboxylic acid

Temperature

65 °C

14 g (250 mmol) of potassium hydroxide were added to 47.3 g (250 mmol) of ethyl 5-chloromethylisoxazole-3-carboxylate in 150 ml of ethanol, and the reaction mixture was stirred for 6 hours at 60-70° C. After cooling, the mixture was concentrated in vacuo, the residue was taken up in water and extracted with ether, the aqueous phase was acidified with hydrochloric acid and subsequently extracted repeatedly with ether, and the ether phase was dried over sodium sulfate and concentrated in vacuo (oil pump, 50° C.). 31 g of the required product resulted (77% of theory)

1. temperatureAfter cooling
2. concentrationthe mixture was concentrated in vacuo
3. extractionextracted with ether
4. extractionsubsequently extracted repeatedly with ether
5. dry with materialthe ether phase was dried over sodium sulfate
6. concentrationconcentrated in vacuo (oil pump, 50° C.)

ORD record

ord-a6726453d7bb47f7847093625a1a8176

Source dataset

uspto-grants-2004_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06740647B1