Linalool.

Related entries: Geraniol

C₁₀H₁₈O = 154.144.

Linalool, C₁₀H₁₈O, is an unsaturated alcohol, isomeric with geraniol. It occurs in a large number of essential oils, such as oils of coriander, lignaloe, bergamot, spike lavender, thyme, etc., and may be either laevorotatory or dextrorotatory. It is obtained by fractional distillation of the oils, which have previously been saponified, and also in the inactive state by treating the chloride produced by the action of hydrochloric acid on geraniol, with alcoholic potash. Linalool occurs as a fragrant, colourless liquid. Specific gravity, 0.870 to 0.875. Boiling-point, 197° to 199°. Refractive index, 1.4611. Rotation, about 20° in either direction. On oxidation with potassium bichromate and sulphuric acid, linalool yields the aldehyde of geraniol, geranialdehyde or citral. The acetate derived from linalool by heating with acetic anhydride is also contained in oil of bergamot, which owes its odour to this ester. Linalyl acetate, C₁₀H₁₇OC₂H₃O, is laevorotatory, and has a specific gravity of 0.912; boiling-point, 105°. When linalool is reduced with sodium and absolute alcohol, or with zinc dust in a sealed tube, at about 220° to 230°, it yields linalolene, C₁₀H₁₈. Oil of coriander consists almost entirely of d-linalool (coriandrol).

The British Pharmaceutical Codex, 1911, was published by direction of the Council of the Pharmaceutical Society of Great Britain.