反应详情

A solution of 3.8 g of the resulting 5-amino-2-chloro-4-fluorothiobenzoic acid (methoxycarbonylmethyl) ester in 100 ml of dichloromethane is added dropwise at from 25° to 30° C. to a suspension of 6 g of calcium carbonate, 4 ml of thiophosgene, 20 ml of dichloromethane and 20 ml of water. When the evolution of carbon dioxide has ceased, the batch is stirred for a further 18 hours at room temperature. After filtering and washing with water, the organic phase is separated off, dried over sodium sulfate and then concentrated by evaporation to yield 4.8 g of 2-chloro-4-fluoro-5-isothiocyanatothiobenzoic acid (methoxycarbonylmethyl) ester in the form of an oil which is used without further purification in the next reaction step.

1. filtrationAfter filtering
2. washwashing with water
3. customthe organic phase is separated off
4. dry with materialdried over sodium sulfate
5. concentrationconcentrated by evaporation