In a 500-ml. three-necked round-bottomed flask equipped with a sealed stirrer, a reflux condenser, a dropping funnel, and a thermometer is placed 78 g. (70 ml., 1 mole) of 2-mercaptoethanol (Note 1). Into the dropping funnel is poured 67 ml. (54.3 g., 1 mole) of acrylonitrile (Note 2), and after the addition of about 3 ml. of the nitrile, with stirring, the contents are warmed with a water bath to about 35–40° for 5 minutes. The remainder of the acrylonitrile is then added dropwise during 10 minutes. The temperature soon mounts to about 65° and is kept between 55° and 60° by intermittent short cooling with water until it only slowly increases or remains stationary at 55–60° (Note 3). Forty milliliters of acrylonitrile is then added all at once, cooling being applied if necessary, and the contents are stirred for 16 hours at room temperature. The product is distilled from a 250-ml. Claisen flask after removal of excess acrylonitrile under reduced pressure. The yield of nitrile distilling at 178–180°/14 mm., n²⁵D 1.5101, as a colorless viscous liquid is 121–123 g. (92–94%) (Note 4).