Acetyl chloride → 4-Methoxy-5-methyl-6-(1-ethyl-5-acetoxypyrazol-4-yl)carbonylthiochroman-1,1-dioxide

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Reaction Steps

4-Methoxy-5-methyl-6-(1-ethyl-5-hydroxypyrazol-4-yl) carbonylthiochroman-1,1-dioxide was used as a starting material (XIH). And, 0.40 g (1.1 mmol) thereof was dissolved in 4 ml of methylene chloride, and 0.22 g (2.2 mmol) of triethylamine as a base and 0.17 g (2.2 mmol) of acetyl chloride as a reaction reagent (XII) were added. The resultant mixture was allowed to react at room temperature for 8 hours. A saturated sodium carbonate aqueous solution was added to the reaction mixture, the reaction mixture was extracted with ethyl acetate, and its organic layer was dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and the resultant oil was purified with flush column chromatography (Wako Gel C-300: hexane/ethyl acetate=1:2) to give 0.33 g (yield 73%) of 4-methoxy-5-methyl-6-(1-ethyl-5-acetoxypyrazol-4-yl)carbonylthiochroman-1,1-dioxide (Compound No. 51) as an end compound which comes under the general formula (XI). Table 18 shows the structures of the starting material (XIH) and the reaction reagent (XII), and the structure and the yield of the end product (XI).

Provenance & Evidence