Triethylamine → [2-(2-Hydroxy-ethoxy)-ethyl]-carbamic acid benzyl ester

To 2-(2-aminoethoxyl)ethanol (20 g) dissolved in dichloromethane (200 ml) was added stepwise triethylamine (26.5 ml) and benzyloxy(carbonyloxy)succinimide (47.47 g). The reaction mixture was stirred overnight at room temperature. The solvent was distilled off under reduced pressure and the residue was dissolved in deionized water (500 ml). The insoluble layer was separated, and the aqueous layer was mixed with 50 g of NaCl and the pH adjusted to 5.0 with 5% H3PO4. The product was extracted with dichloromethane (100 ml, 50 ml, and 50 ml) and the extract was dried with MgSO4, filtered, and evaporated to dryness under reduced pressure. The residue was dried under vacuum overnight, then combined with the previously separated insoluble layer and dissolved in dichloromethane (300 ml). The solution was washed with 5-% aqueous NaCl solution (3×50 ml) and dried with MgSO4. The solvent was distilled under reduced pressure, and the residue was dried overnight under vacuum, giving 40 g of the desired product.