Ethylenediamine → 2-(2-Aminoethyl)-1-phenylisoindoline

A solution of 127 g. (0.59 mole) of 2-hydroxymethylbenzhydrol was dissolved in 900 ml. of benzene, 80 g. of anhydrous magnesium sulfate was added and the mixture was cooled in an ice bath. Hydrogen bromide was bubbled into the stirred solution until saturation which took about 30 minutes. During this time the temperature of the solution was kept at 15°-18°. The ice bath was removed and the temperature was allowed to rise to 35° in the course of 1 hour. The mixture was heated for another hour at 40°-45° on a steam bath. During the whole time hydrogen bromide was passed into the solution to keep it saturated. The mixture was filtered and the solution was concentrated in vacuo to give a red oil which was dissolved in 200 ml. of benzene and added to 342 g. (5.7 moles) of ethylenediamine in the course of 15 minutes. During the addition the mixture was stirred and cooled to maintain a temperature of ca. 40°. The mixture was stirred at 25° for 70 minutes. Two layers were obtained and separated. The benzene layer was washed with water and concentrated in vacuo. The residual oil was dissolved in 250 ml. of ether. This solution was extracted twice with 300 ml. of cold 1N hydrochloric acid. The acidic aqueous phase was made alkaline with aqueous sodium hydroxide and extracted with 350 ml. of ether. The ethereal solution was washed with 250 ml. of water, dried and concentrated. The residue was an amber oil which crystallized on scratching. This material melted up to ca. 45°.