周邦基. 氯霉素,Ⅱ.α-溴代-对-硝基苯乙酮的合成J. 药学学报, 1960, 8(1): 43-46.
引用本文: 周邦基. 氯霉素,Ⅱ.α-溴代-对-硝基苯乙酮的合成J. 药学学报, 1960, 8(1): 43-46.
CHOU PANG-TE. CHLORAMPHENICOL, Ⅱ. SYNTHESIS OF α-BROMO-p-NITROACETOPHENONEJ. Acta Pharmaceutica Sinica, 1960, 8(1): 43-46.
Citation: CHOU PANG-TE. CHLORAMPHENICOL, Ⅱ. SYNTHESIS OF α-BROMO-p-NITROACETOPHENONEJ. Acta Pharmaceutica Sinica, 1960, 8(1): 43-46.

氯霉素,Ⅱ.α-溴代-对-硝基苯乙酮的合成

CHLORAMPHENICOL, Ⅱ. SYNTHESIS OF α-BROMO-p-NITROACETOPHENONE

  • 摘要: 本文叙述了二种制备氯霉素的重要中間体α-溴代-对-硝基苯乙酮的方法。(一) α-苯基-β-溴代乙醇(Ⅱ)經硝化生成α-对-硝基苯基-β-溴代乙醇硝酸酯(Ⅲ),将此硝酸酯直接水解即生成相应的醇,但以先轉化成α-对-硝基苯基-β-溴代乙醇乙酸酯(Ⅳ),然后醇解成α-对硝基苯基-β-溴代乙醇(Ⅴ)收率較高,后者可用鉻酸氧化成α-溴代-对-硝基苯乙酮(Ⅳ),由最初原料苯乙烯(Ⅰ)計算全程收率分別为37.2%与40.8%。(二) β-溴代乙苯(Ⅶ)依次經硝化及氧化作用亦生成α-溴代-对-硝基苯乙酮(Ⅵ),全程收率50.8%。

     

    Abstract: Two methods for the preparation of α-bromo-p-nitroacetophenone (Ⅵ), a useful intermediate for the synthesis of chloramphenicol, are described. Styrene bromohydrin (Ⅱ) obtained by the addition of HOBr to styrene (Ⅰ) was nitrated to α-p-nitrophenyl-β-bromoethyl nitrate (Ⅲ). The nitrate (Ⅲ) was then hydrolized directly to p-nitrostyrene bromohydrin (Ⅴ), or preferably through its acetate (Ⅳ) by alcoholysis. The bromohydrin (Ⅴ) was oxidized with chromic acid in acetic acid to give α-bromo-p-nitroacetophenone (Ⅵ) in over-all yields of 37.2% and 40.8% respectively. α-Bromo-p-nitroacetophenone (Ⅵ) can also be obtained by nitration of β-bromoethyl benzene (Ⅶ) followed by oxidation of the resulting p-nitro compound (Ⅷ) in an over-all yield of 50.8%.

     

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