Nomenclature

2,2,2-Trichloro-1,1-ethanediol; trichloroacetaldehyde monohydrate; Escre (SS Pharm.); Noctec (BMS); Nycton; Somnos (Merck & Co.); Chloraldurat (Pohl).

C₂H₃Cl₃O₂; mol wt 165.40.

Properties

Large, monoclinic plates. Perfect 001 cleavage. Skin irritant. Aromatic, penetrating and sightly acrid odor, slightly bitter, caustic taste. Slowly volatilizes on exposure to air. d 1.91. mp 57° when heated in an open vessel. bp 98° with dissociation into chloral and water. Freely sol in water. One ml of water dissolves the following amounts of chloral hydrate: 2.4 g at 0°, 8.3 g at 25°, 14.3 g at 40°. One gram of chlorate hydrate dissolves in 1.3 ml alcohol, in 2 ml chloroform, in 1.5 ml ether, in 1.4 ml olive oil, in 0.5 glycerol, in 68 g carbon disulfide. Freely sol in acetone, methyl ethyl ketone. Moderately or sparingly sol in turpentine, petr ether, carbon tetrachloride, benzene, toluene. Dissociation in water: Piguet et al., Helv. Chim. Acta 46, 406 (1963). An alcoholic soln of chloral hydrate (1 in 20) does not at once redden moistened blue litmus paper. Dec by NaOH into chloroform. Reduces ammoniacal AgNO₃. Liquefies when triturated with an equal quantity of menthol, camphor or thymol. LD₅₀ orally in rats: 479 mg/kg (Goldenthal).