Hydrochloric Acid → 3-cyano-3-Hydroxy-4-Chlorobutyric Acid

Beteiligte Stoffe

Reaktionsschritte

68.8 g of 3-oxo-4-chlorobutyric acid (94.2 percent purity by NMR) (0.476 mols) was mixed with 200 ml of distilled water in a three neck flask fitted with a thermometer, dropping funnel, stirrer and connected via an ice condenser to a nitrogen bubbler which was connected to a NaOh trap in series. Sodium cyanide (24.5 g) (0.50 mol) was dissolved in 75 ml of water and placed in the dropping funnel. The contents of the flask were cooled in an ice bath and the NaCN solution added at 10°-15°C to give a pH of 8. The mixture was brought to a pH of 0.8 with 46 ml (0.568 mol) concentrated HCl and then extracted with five 100 ml. portions of ether. The combined ether extract was dried with anhydrous MgSO4. After filtering off the drying agent and washing the solids with ether, the ether was evaporated on a rotary evaporator at 35°-40°C. Assay of the 78.3 g of product by NMR showed 80.6 percent 3-cyano-3-hydroxy-4-chlorobutyric acid, 8.22 percent water, 3.53 percent acetoacetic acid and 7.6 percent ether. The last traces of ether and water were quite difficult to remove. The yield was 82 percent.

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