In an open
3-l. three-necked flask, equipped with an
efficient mechanical stirrer (Note
1) and two
dropping funnels, are placed 500 ml. of water,
250 ml. of technical naphtha boiling at
95–110°, and
195 g. (1.5 moles) of freshly distilled ethyl acetoacetate. The mixture is cooled to 5° with a
water-ice bath, and
65 ml. of 33% sodium hydroxide solution
(33 g. sodium hydroxide in 100 g. solution) is added. As the temperature is maintained below 10° (Note
2) and the pH near 11 (Note
3), the mixture is stirred vigorously (Note
1), and there are added simultaneously from the two dropping funnels
230 g. (1.62 moles) of benzoyl chloride and
270 ml. of 33% sodium hydroxide solution. This addition should be made during about 2 hours. After addition is complete, the cooling bath is removed, and the mixture is allowed to come to room temperature. In order to ensure complete reaction, the mixture is finally brought to 35° during about 1 hour. The stirrer is then stopped, and the aqueous layer is separated and placed in a
2-l. Erlenmeyer flask (Note
4).
To the mixture is added
80 g. of technical ammonium chloride; then it is stirred slowly overnight. The specific gravity is brought to 1.13 by the addition of about
90 g. of sodium chloride, after which the mixture is transferred to a
separatory funnel. About
10 ml. of benzene is used to rinse the flask and is added to the separatory funnel. The aqueous layer is withdrawn (Note
5), and the oil is washed three times with 100-ml. portions of cold water.