Reaction #1163

Reaction equation

4-methoxyimino-5-methyl-6-(1-ethyl-5-hydroxypyrazol-4-yl)carbonylthiochroman-1,1-dioxide

pyrazole

phenacyl bromide

potassium carbonate

→

4-methoxyimino-5-methyl-6-(1-ethyl-5-phenacyloxypyrazol-4-yl)carbonylthiochroman-1,1-dioxide

Yield 52.0%

Solvents

acetone

Conditions

Workup

1. 1
   Temperatureunder heat for 8 hours
2. 2
   OtherInsolubles were removed by filtration
3. 3
   workup.DISTILLATIONthe acetone was distilled off
4. 4
   workup.DISSOLUTIONThe residue was dissolved in ethyl acetate
5. 5
   Washthe mixture was washed with a saturated sodium chloride aqueous solution
6. 6
   Dryingdried over sodium sulfate
7. 7
   workup.DISTILLATIONThe ethyl acetate was distilled off under reduced pressure

Procedure

0.4 Gram (1.1 mmol) of 4-methoxyimino-5-methyl-6-(1-ethyl-5-hydroxypyrazol-4-yl)carbonylthiochroman-1,1-dioxide corresponding to pyrazole derivative (I-H), 0.23 g (1.2 mmol) of phenacyl bromide corresponding to compound B-A-Hal and 0.15 g of potassium carbonate were added to 10 ml of acetone, and the mixture was stirred under heat for 8 hours. Insolubles were removed by filtration, and then the acetone was distilled off. The residue was dissolved in ethyl acetate, and the mixture was washed with a saturated sodium chloride aqueous solution and dried over sodium sulfate. The ethyl acetate was distilled off under reduced pressure, and the residue was subjected to column chromatography (hexane/ethyl acetate) to give 4-methoxyimino-5-methyl-6-(1-ethyl-5-phenacyloxypyrazol-4-yl)carbonylthiochroman-1,1-dioxide (Compound Ib-2) at a yield of 52%.

Source