The general procedure for the synthesis of 3,3'-iminobis-1-propanol from 3-amino-1-propanol and 3-chloro-1-propanol was as follows: a mixture of 3-amino-1-propanol (45 mL, 0.59 mol), 3-chloro-1-propanol (25 mL, 0.30 mol), and water (130 mL) was reacted for 24 hr under reflux conditions. Subsequently, potassium hydroxide was added to the reaction mixture. After the potassium hydroxide was completely dissolved, all water was removed by evaporation to obtain a mixture containing viscous oil and a large amount of potassium chloride. The solid potassium chloride was separated by filtration and the filter cake was washed with dry acetone. The combined organic phases were dried with anhydrous magnesium sulfate, filtered and the solvent evaporated to give a dark brown oil. The oily substance was purified by distillation under reduced pressure to afford the target product 3,3'-iminobis-1-propanol as a colorless or pale yellow liquid (yield: 31.5 g, 0.24 mol, yield: 80%). The 1H NMR (CDCl3) data of the product were as follows: δ 1.73 (quadruple peak, 4H, N-CH2-CH2-CH2-OH), 2.81 (triple peak, 4H, N-CH2-CH2-CH2-OH), 3.20 (single peak, 3H, HN-CH2-CH2-CH2-OH), 3.75 (triple peak, 4H, N-CH2- CH2-CH2-OH).
