反应详情

To 80 ml of methanol solution containing 0.92 g of metallic sodium were added 7.8 g of methyl 2,2-dimethyl-3-(2',2',2'-trichloroethyl)-cyclopropanecarboxylate (purity: 87.8%, cis/trans ratio: 88/12) to heat the resulting mixture for 35 hours under reflux. After distilling off the methanol, the mixture was diluted with water, acidified with diluted hydrochloric acid, subjected to extraction with ether. After washing the ether layer with sodium bicarbonate aqueous solution and a saturated sodium chloride aqueous solution, the ether was distilled off. Vacuum distillation was carried out to obtain 5.4 g of methyl 2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylate, b.p. 64°-72° C./1.2 mmHg, cis/trans ratio 90.9/9.1, purity 87.8%, yield 79.8%. Further, the sodium bicarbonate aqueous wash solution was acidified to obtain 0.5 g of 2,2-dimethyl-3-(2',2'-dichlorovinyl)-cyclopropanecarboxylic acid.

1. temperatureto heat the resulting mixture for 35 hours
2. temperatureunder reflux
3. distillationAfter distilling off the methanol
4. additionthe mixture was diluted with water
5. extractionsubjected to extraction with ether
6. washAfter washing the ether layer with sodium bicarbonate aqueous solution
7. distillationa saturated sodium chloride aqueous solution, the ether was distilled off
8. distillationVacuum distillation