Submitted by Lawrence H. Amundsen and James J. Sanderson.
Checked by R. L. Shriner and John L. Rendall.
1. Procedure
In a
500-ml. distilling flask are placed
107 g. (0.40 mole) of γ-bromopropylphthalimide (Note
1) and
240 ml. of xylene. Solution is effected by heating, and
24 ml. of xylene is distilled to remove traces of moisture. After cooling, the solution is transferred to a
1-l. round-bottomed flask with a ground-glass joint and treated with
107 g. (140 ml., 0.83 mole) of di-n-butylamine. The flask is fitted with a
reflux condenser and heated with occasional shaking for 10 hours in an
oil bath maintained at 140–150°.
The solution is allowed to cool, and the
di-n-butylamine hydrobromide, which separates in the course of the reaction, is removed by means of a
suction filter (Note
2). The filtrate is transferred to a 500-ml. distilling flask, and the
xylene is removed by distillation. The crude
γ-di-n-butylaminopropylphthalimide, a brown oil, is transferred to a 500-ml. round-bottomed flask with a ground-glass joint and treated with 20 ml. of water and
120 ml. of 12 N hydrochloric acid. The flask is fitted with a reflux condenser, and the solution is heated for 6 hours in an oil bath maintained at 140–150°. After the solution has cooled to room temperature, the precipitated
phthalic acid is removed by filtration and washed with four 25-ml. portions of cold water. The combined filtrates are transferred to a
600-ml. beaker and heated on a
steam bath to evaporate the water and
hydrochloric acid.
The dried
benzene extract is placed in a 500-ml. round-bottomed flask with a ground-glass joint. The flask is fitted with a
Vigreux column, and the
benzene is distilled from the solution at atmospheric pressure, an oil bath maintained at 100–110° being the source of heat. The crude
γ-di-n-butylaminopropylamine is fractionated under reduced pressure from a
250-ml. Claisen flask; heat is supplied by an oil bath maintained at 170–180°. The yield of product boiling at
108–110.5°/5–6 mm. or
98–100°/2 mm. amounts to
57–60 g. (
77–80%) (Note
4).
2. Notes
3. The increase in volume of the first portion is about 75 ml. There is no noticeable increase in the volumes of the two 50-ml. portions.
3. Discussion
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