反应详情

温度

-40 °C

Oxalyl chloride (0.78 g, 6.2 mmol) was dissolved in dichloromethane (12 ml), and the solution was cooled to -40° C. A solution of dimethylsufloxide (1.0 g, 12.3 mmol) in dichloromethane (4 ml) was dropwise added thereto over a period of 10 minutes. Fifteen minutes later, a solution of 2-(4-hydroxy-2-butynyl)cyclopropanecarboxylic acid methyl ester (0.70 g, 4.1 mmol) in dichloromethane (5 ml) was dropwise added thereto over a period of 15 minutes. Forty minutes later, triethylamine (2.5 g, 25 mmol) was added thereto, and the temperature was raised to 0° C. Water was added thereto, and the product was extracted with dichloromethane, and the crude product thereby obtained was roughly separated by silica gel column chromatography to obtain 2-(4-oxo-2-butynyl)cyclopropanecarboxylic acid methyl ester (0.32 g).

1. waitover a period of 15 minutes
2. temperaturethe temperature was raised to 0° C
3. extractionthe product was extracted with dichloromethane
4. customthe crude product thereby obtained
5. customwas roughly separated by silica gel column chromatography