In a
1-l. three-necked flask fitted with a
stirrer, a
thermometer, and an
ice-cooled spiral condenser (Org. Syn. Coll. Vol. I, 1941, 529) is placed a solution of
98 g. (84.5 cc., 0.8 mole) of ethyl chloroacetate (Note 2, p. 263) in
200 cc. of absolute alcohol. The solution is cooled to 0° by stirring in a
salt-ice bath; and, after the stirrer is stopped,
74 cc. (49 g., 0.83 mole) of trimethylamine, measured after precooling to −5°, is added all at once. The exothermic reaction is controlled sufficiently by cooling so that the temperature of the mixture rises to 60° in the course of about one hour (Note
1). When there is no longer any heat effect, the mixture is allowed to stand at room temperature for twenty hours (without replenishment of the condenser ice).
The condenser is removed, the thermometer replaced by a
dropping funnel, and
40 g. (0.8 mole) of 100 per cent hydrazine hydrate (Note
2) added, with stirring, in the course of ten to fifteen minutes. After being stirred for forty-five minutes longer, the solution is cooled slightly, and, unless crystallization of the reaction product starts spontaneously, the walls of the vessel are scratched with a glass rod to induce crystallization (Note
3). The product separates in fine, colorless needles. After being thoroughly cooled in an
ice bath, the highly hygroscopic salt is collected quickly on a
Büchner funnel, washed with
150 cc. of cold absolute alcohol, and pressed dry under a
rubber dam. Dried in a
vacuum desiccator over concentrated
sulfuric acid, this material weighs
100–108 g. A further crop can be obtained after distilling 200–300 cc. of solvent from the mother liquor and washings at the pressure of the
water pump. The total yield of salt, m.p.
175–180°, with decomposition, is
112–120 g. (
83.5–89.5 per cent of the theoretical amount) (Note
4), (Note
5), and (Note
6).