反应详情

29.5 g (77.5 mmol) of borax and 24.8 g (0.62 mol) of sodium hydroxide are dissolved in 310 ml of water and treated while cooling (17° C.) with 65 g (310 mmol) of 3-carboethoxy-2-cyano-3,5-dimethylcyclopentanone (prepared from ethyl methacrylate and sodium cyanide according to H. Stetter et al, Liebig's Annalen d. Chem. 1979, 944-949). 132.2 g (403 mmol) of Caroat dissolved in 428 ml of water are added dropwise at 13° C. to 19° C. within 25 minutes and the mixture is stirred at room temperature for 3 hours. For the working-up, the mixture is acidified with 30 ml of sulphuric acid (2:1) and extracted four times with ethyl acetate. The organic phase is dried over sodium sulphate, concentrated and dried in a high vacuum for 2 hours. There are obtained 69.8 g (100%) of 3-carboethoxy-2-cyano-2-hydroxy-3,5-dimethylcyclopentanone in the form of a diestereomeric mixture: nD20 =1.4658.

1. additiontreated
2. additionare added dropwise at 13° C. to 19° C. within 25 minutes
3. extractionextracted four times with ethyl acetate
4. dry with materialThe organic phase is dried over sodium sulphate
5. concentrationconcentrated
6. customdried in a high vacuum for 2 hours