Phthalimide → 2-[2-(Hexyloxy)ethoxy]ethanamine

Participants

Reaction Steps

A mixture of ethylene glycol mono-n-hexyl ether (15.0 g, 0.1 mol) and sodium hydride (0.1 mol) was dissolved in dry DMF (150 mL). After the mixture was stirred for 1-2 hours, N-(2-bromoethyl)phthalimide (25.4 g, 0.1 mol) was added with continued stirring and the mixture was warmed on a steam bath for 8 h. The DMF was then removed by evaporation and the residue dissolved in hot toluene, and the solution was concentrated to remove solvent. The residue was purified using silica gel chromatography using ethyl acetate to give 25 g (78%). 1H NMR (CDCl3, TMS): δ 0.87 (t, 3H, J=6.8Hz), 1.24˜1.30 (m, 8H), 1.56˜1.60 (m, 2H), 3.47 (t, 3H, J=6.8 Hz), 3.72 (dd, 2H, J1=4.4 Hz, J2=5.6 Hz), 4.06 (t, 3H, J=9.6 Hz), 4.41˜4.46 (m, 4H) 7.50˜7.52 (m, 2H), 7.72˜7.76 (m, 2H). A solution of the thus-derived isoindoledione and hydrazine hydrate (5.5 g, 0.11 mol) in EtOH (200 mL) was heated at reflux for 8 hours. The precipitate (phthalhydrazide) was removed by filtration, and the filtrate was concentrated to low volume and refiltered. The filtrate was then concentrated to dryness, treated with water (20 mL) and sodium hydroxide (11 g), and extracted with methylene chloride (4×100 mL). The combined organic layers are dried over MgSO4, concentrated, and purified by silica gel to provide 7 g of the amine product (50%). 1H-NMR (CDCl3, TMS): δ 0.89 (t, 3H, J=6.8 Hz), 1.29˜1.36 (m, 6H), 1.55˜1.60 (m, 2H), 2.03 (m, 2H), 3.45˜3.49 (m, 4H), 3.53˜3.55 (m, 2H), 3.71˜3.74 (m, 2H).

Provenance & Evidence