A solution of 134 g. (0.81 mole) of chloral hydrate (Note 1) in 400 ml. of ether (Note 2) is placed in a 2-l. round-bottomed three-necked flask equipped with a dropping funnel, a reflux condenser, and an efficient mercury-sealed stirrer (Note 3). A solution of 12 g. of potassium cyanide (Note 4) in 220 ml. of concentrated ammonium hydroxide (sp. gr. 0.9) is added through the dropping funnel over the course of 15 minutes at a rate sufficient to cause the ether to reflux vigorously. Stirring is continued for an additional 20 minutes (Note 5). The layers are separated, and the ether layer is washed once with 75 ml. of water and once with 75 ml. of 10% aqueous sulfuric acid solution (Note 6). (These washings are retained and used again later.) The aqueous layer from the reaction mixture is extracted with three 75-ml. portions of ether, and each ether extract is washed successively with the same water and sulfuric acid solutions used previously. The combined ether extracts are dried with 40 g. of sodium sulfate, the ether is removed by distillation, and the residue is recrystallized from 200 ml. of benzene. The solid is removed by filtration with suction and washed with two 25-ml. portions of cold benzene. The yield is 66–76 g. melting at 97.5–99.5° (cor.). Concentration of the filtrate gives 1–5 g. of material with a slightly lower (96–97° cor.) melting point, making the total yield 67–81 g. (65–78%).