反应详情

8.3 ml (108 mmol) methyl chloroformate dissolved in 25 ml tetrahydrofuran (THF) is added dropwise over 15 minutes to a solution of 23.9 g (107 mmol) 4-(acetylamino)-3-nitrobenzoic acid and 14.8 ml (107 mmol) triethylamine in 150 ml dry THF under nitrogen and chilled in an acetone/ice bath. The temperature is kept below -5°. After stirring at -5° for 30 minutes, the triethylamine.HCl is filtered off and washed with 30 ml cold THF. The combined filtrates are added dropwise to a stirred solution of 10.3 g (108 mmol) sodium borohydride in 100 ml water chilled in an acetone/ice bath. The temperature is not allowed to exceed 15°. The resulting mixture is stirred at room temperature for 4 hours. After acidification with concentrated hydrochloric acid, the reaction mixture is taken up in ethyl acetate which is washed with water, 10% NaOH (X 2), water (X 2), dried (Na2SO 4), and evaporated: 17 g. This material is crystallized from 20 ml methanol to give 9.1 g of the title compound, m.p. 114°-115°.

1. temperaturechilled in an acetone/ice bath
2. customis kept below -5°
3. filtrationHCl is filtered off
4. washwashed with 30 ml cold THF
5. temperaturechilled in an acetone/ice bath
6. customto exceed 15°
7. stirringThe resulting mixture is stirred at room temperature for 4 hours
8. washis washed with water, 10% NaOH (X 2), water (X 2)
9. dry with materialdried (Na2SO 4)
10. customevaporated
11. customThis material is crystallized from 20 ml methanol