The central neck of a
5-l. three-necked round-bottomed flask is fitted with a stopper carrying a
mercury-sealed mechanical stirrer. One of the side necks is connected by means of a short piece of heavy rubber tubing to a
large reflux condenser about 2 m. long, with an inner tube 2.5 cm. in diameter (Note
1). The third neck is fitted with a
separatory funnel.
In the flask are placed
70 g. (3 moles) of sodium and
200 cc. of dry toluene (Note
2). The flask is heated in an
oil bath until the
sodium is melted. The stirrer is then started; when the
sodium is finely divided, the oil bath is removed and the mixture allowed to cool. Stirring must be continued during the cooling in order to keep the
sodium finely divided.
When the mixture has cooled to about 60°, there are added from the separatory funnel, first, a solution of
114 g. (0.5 mole) of ethyl laurate (Note
3) in
150 cc. of absolute alcohol (Note
4), then
500 cc. more of alcohol, as rapidly as is possible (Note
5) without loss of material through the condenser. The time required for the addition of the ester solution and the alcohol is less than five minutes, usually two or three minutes. When the reaction has subsided, the flask is heated on a steam bath until the
sodium is completely dissolved (Note
6). The mixture is then steam-distilled to remove the
toluene and
ethyl alcohol. The contents of the flask are transferred to a separatory funnel while still hot and washed three times with 200-cc. portions of hot water to remove the
sodium laurate (Note
7). The
lauryl alcohol is extracted with
ether from the cooled mixture and the washings. The combined
ether extracts are washed with water,
sodium carbonate solution, and again with water, and dried over anhydrous
magnesium sulfate. The ether is evaporated and the
lauryl alcohol distilled under diminished pressure. The yield is
60–70 g. (
65–75 per cent of the theoretical amount) of a product boiling at
143–146°/18 mm. or
198–200°/135 mm. (Note
8).