反应详情

To 50 ml of ethyl acetate, there were added 4.61 g (24.4 mmol) of N-(tert-butoxycarbonyl)-β-alanine and 5.03 g (24.4 mmol) of N,N'-dicyclohexyl carbodiimide and stirred at room temperature for 30 minutes. To the solution thus obtained, there were added 3.00 g (24.4 mmol) of 6-amino-m-cresol and 2.51 g (24.4 mmol) of triethylamine and stirred at room temperature for 17 hours. After the completion of the reaction, 100 ml of ethyl acetate was added to the solution. After filtering insoluble crystals, the filtrate was washed with 1N hydrochloric acid, a saturated aqueous solution of sodium hydrogencarbonate and a saturated aqueous solution of common salt and dried over anhydrous Glauber's salt. After distilling off the solvent under reduced pressure, the brown solid thus obtained was subjected to silica gel column chromatography (Si60 manufactured by Merck; 230-400 mesh; 300 g; eluent: 5% methanol-chloroform). After distilling off the solvent from the 600-1,200 ml fraction under reduced pressure, pale brown crystals were obtained. These crystals were recrystallized from chloroform and thus 1.56 g (5.3 mmol) of N-(2-hydroxy-4-methylphenyl)-3-(tert-butoxy-carbonyl)aminopropionamide was obtained as pale brown crystals. The yield was 22%.

1. customTo the solution thus obtained
2. stirringstirred at room temperature for 17 hours
3. additionwas added to the solution
4. filtrationAfter filtering insoluble crystals
5. washthe filtrate was washed with 1N hydrochloric acid
6. dry with materiala saturated aqueous solution of sodium hydrogencarbonate and a saturated aqueous solution of common salt and dried over anhydrous Glauber's salt
7. distillationAfter distilling off the solvent under reduced pressure
8. customthe brown solid thus obtained
9. distillationAfter distilling off the solvent from the 600-1,200 ml fraction under reduced pressure
10. custompale brown crystals were obtained
11. customThese crystals were recrystallized from chloroform