反应详情

The method described in Part B of Example 3 was repeated with 1-tetrahydro-4H-pyran-4-ylideneacetone (4.0 g, 28.5 mmol), and the resulting 1-tetrahydro-2H-pyran-4-ylacetone was mixed with diethyl oxalate (4.66 g, 31.9 mmol) and added to a solution of sodium tert-butoxide (3.07 g, 31.9 mmol) in ethanol (22 mL). The reaction was carried out according to the method described in Part C of Example 3 with the following modifications. Hydroxyethylhydrazine (2.43 g, 31.9 mmol) was used instead of ethylhydrazine oxalate. Extractions were carried out seven times with chloroform, and the crude product was not purified. Ethyl 1-(2-hydroxyethyl)-5-(tetrahydro-2H-pyran-4-ylmethyl)-1H-pyrazole-3-carboxylate (8.2 g) was obtained as a viscous yellow oil.

1. extractionExtractions
2. customthe crude product was not purified