反应详情

温度

100 °C

Phenyl acetyl chloride (2.2 ml.) was added to a stirred solution of ethyl 2-(3-amino-4-hydroxyphenyl)propionate (3.15g.) in anhydrous pyridine (50 ml.) and the solution was heated at 100° C for two hours. Excess pyridine was removed by distillation and the residue heated until the temperature of the distillate immediately above the reaction mixture was 200° C. The resultant dark brown gum was dissolved in ether (75 ml.) and then washed with water (3 × 50 ml.) The ether solution was extracted with 1N sodium hydroxide (50 ml.), washed with water (2 × 50 ml.) and evaporated to give ethyl 2-(2-benzyl-5-benzoxazolyl)propionate as a light brown mobile gum, which was shown to be pure by thin layer chromatography. Similarly the following esters were prepared and characterised:

1. customExcess pyridine was removed by distillation
2. temperaturethe residue heated until the temperature of the distillate immediately above the reaction mixture
3. customwas 200° C
4. dissolutionThe resultant dark brown gum was dissolved in ether (75 ml.)
5. washwashed with water (3 × 50 ml.) The ether solution
6. extractionwas extracted with 1N sodium hydroxide (50 ml.)
7. washwashed with water (2 × 50 ml.)
8. customevaporated