反应详情

3.24 g of 3-acetoxy-2-cyclobuten-1-one (triketene, 97.5 percent; 25.0 mmol) was dissolved in 1.9 g of ethanol (41.3 mmol) and 40 g of ethyl acetate. 9.83 g of dicyclohexylmethylamine (98.9 percent; 50.0 mmol), dissolved in 10 g of ethyl acetate, was instilled in this solution at 20° C. in 15 minutes and stirred for 1 hour at room temperature. After another hour of stirring at 5° C., the suspension was filtered and dried under vacuum. 3.21 g of the title product with a content of 94.5 percent (according to HPLC), corresponding to a yield of 43.5 percent, relative to the 3-acetoxy-2-cyclobuten-1-one, was obtained. Data for the title compound was:

1. stirringAfter another hour of stirring at 5° C.
2. filtrationthe suspension was filtered
3. customdried under vacuum