反应详情

A mixture of 4-[N-methyl-N-(5-chloro-2-benzoxazolyl)amino]phenol (1.0 g, 0.0039 mole; see Example 7 part (a), ethyl 4-bromovalerate (0.89 g, 0.0043 mole), anhydrous potassium carbonate (0.54 g) and methyl isobutyl ketone (15 ml) was heated under reflux for a period of 30 hours with further portions (0.05 g) of anhydrous potassium carbonate being added at 3 hour intervals. The reaction mixture was cooled, filtered and the filtrate was distilled under reduced pressure to remove the solvent. The residue (a red oil) was distilled under reduced pressure, bp 240°-260° C. at 0.04 mm Hg and the distillate was further purified by preparative thin layer chromatography on silica gel (eluent chloroform/ethanol 15:1) to give the title compound (0.47 g) as a red oil. The pmr and mass spectra of the compound were consistent with the assigned structure.

1. temperaturewas heated
2. additionadded at 3 hour intervals
3. temperatureThe reaction mixture was cooled
4. filtrationfiltered
5. distillationthe filtrate was distilled under reduced pressure
6. customto remove the solvent
7. distillationThe residue (a red oil) was distilled under reduced pressure, bp 240°-260° C. at 0.04 mm Hg
8. distillationthe distillate was further purified by preparative thin layer chromatography on silica gel (eluent chloroform/ethanol 15:1)