γ-Di-n-Butylaminopropylamine (CAS NO.: ), which is also known as 1,3-diamine, N,N-di-n-butyl-, could be produced through the following synthesis routes.

In a 500-ml. distilling flask are placed 107 g. (0.40 mole) of γ-bromopropylphthalimide 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. 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 residue, a thick brown oil, which is crude γ-di-n-butylaminopropylamine dihydrochloride, is treated with a solution of 80 g. of potassium hydroxide in 80 ml. of water. A brown oil separates above the aqueous layer, which contains a considerable amount of solid potassium chloride. The whole is extracted with one 200-ml. portion and two 50-ml. portions of benzene. The combined extracts are then placed in a 500-ml. Erlenmeyer flask over 50 g. of potassium hydroxide and allowed to dry overnight.

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%).