反应详情

N,2-Dihydroxybenzenecarboximidoyl chloride in 100 mL of ethanol was added to sodium salt of ethyl 2-methyl4,6-dioxocyclohexanecarboxylate in a solvent mixture of 125 mL of water and 75 mL of ethanol at a temperature of 55° C. over an hour. The reaction mixture was maintained at this temperature for 4 hours and then cooled down to room temperature. After diluting with water (100 mL), the mixture was extracted with ethyl acetate (2×100 mL). The resulting extract was washed with saturated sodium chloride aqueous solution (150 mL), dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. The residue was treated with diethyl ether to give the product (2.48 g) as white powders. The residue was further purified by silica gel preparative thin layer chromatography to give additional 2.15 g of the product as white powders (total amount yielded at the 2 steps: 4.63 g, yield: 60%). The physicochemical properties of the compound obtained are shown below.

1. temperatureThe reaction mixture was maintained at this temperature for 4 hours
2. extractionthe mixture was extracted with ethyl acetate (2×100 mL)
3. extractionThe resulting extract
4. washwas washed with saturated sodium chloride aqueous solution (150 mL)
5. dry with materialdried over anhydrous sodium sulfate
6. concentrationconcentrated under reduced pressure
7. additionThe residue was treated with diethyl ether