To a stirred mixture of 5-amino-1-pentanol (48.5 mmol, 5.0 g) and sodium bicarbonate (145.4 mmol, 12.2 g) in water (26 mL) was slowly added a solution of benzyl chloroformate (63.1 mmol, 9.0 mL) in THF (26 mL) dropwise at 0-5 °C. After the dropwise addition was completed, the reaction mixture was stirred at room temperature overnight. After completion of the reaction, the organic layer was separated by diluting the reaction mixture with EtOAc and water. The organic layer was washed with brine (2 x 30 mL), dried over anhydrous MgSO4, filtered and concentrated under reduced pressure to remove the solvent. The crude product was dispersed with a minimal amount of cyclohexane and the resulting solid was filtered and dried under vacuum to give 5-(Cbz-amino)-1-pentanol as a white solid (8.2 g, 71%).1H NMR (400 MHz, CDCl3) δ 7.35 (m, 5H), 5.09 (s, 2H), 4.8 (brs, 1H), 3.65 (m, 2H), and 3.20 (m, 2H), 1.50-1.58 (m, 6H), 1.39 (m, 2H).
