反应详情

With thorough cooling 13.6 g of 3-chloro-4-cyclohexyl-α-(2-carboxyethyl)-hydratropic acid are dissolved in 70 ml of 100% sulfuric acid and the solution is kept over-night at room temperature, then cautiously poured out over ice and the aqueous mixture is extracted with ethyl acetate and the extract is evaporated. The resulting crystals are recrystallized from acetone, to yield 11.5 g of 1-methyl-4-oxo-6-cyclohexyl-7-chloro-1,2,3,4-tetrahydronaphthalene-1-carboxylic acid, melting at 227°-228°C, of the formula ##SPC5##

1. waitthe solution is kept over-night at room temperature
2. additioncautiously poured out over ice
3. extractionthe aqueous mixture is extracted with ethyl acetate
4. customthe extract is evaporated
5. customThe resulting crystals are recrystallized from acetone