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7-氯-2-氧代庚酸乙酯是合成西司他丁的中间体。以二氯乙酸为起始原料,酯化制成2,2-二乙氧基乙酸乙酯,收率55·6%,2,2-二乙氧基乙酸乙酯与1,3-丙二硫醇成环生成1,3-二噻烷-2-羧酸乙酯,收率72·4%;1,3-二噻烷-2-羧酸乙酯再与1-溴-5-氯戊烷烷基化反应后经氧化到7-氯-2-氧代庚酸乙酯,收率80%。本路线简化了2,2-二乙氧基乙酸乙酯的合成工艺,用1-溴-5-氯戊烷代替1,5-二溴戊烷,减少了双烷基化副反应,使收率有所提高。
Ethyl 7-chloro-2-oxoheptanoate is an intermediate for the synthesis of cilastatin. Dichloroacetic acid as starting material, esterification made of 2,2-diethoxyacetate, yield 55.6%, 2,2-diethoxyethyl acetate and 1,3-propanediol Thiol to form 1,3-dithiane-2-carboxylic acid ethyl ester, yield 72.4%; ethyl 1,3-dithiane-2-carboxylate was reacted with 1-bromo- Pentane alkylation was oxidized to ethyl 7-chloro-2-oxoheptanoate in 80% yield. This route simplifies the synthesis of ethyl 2,2-diethoxyacetate using 1-bromo-5-chloropentane instead of 1,5-dibromopentane, reducing the double alkylation side reactions Rate has improved.