Benzyl chloroformate → benzyl 2-(2-hydroxyethoxy)ethylcarbaMate

2-(2-Aminoethoxy)ethanol (5.26 g, 50 mmol) and sodium hydroxide (2.1 g, 52.5 mmol) were dissolved in water (200 mL). The resulted solution was cooled in ice bath, followed by the dropwise addition of benzyl chloroformate. After the addition, the reaction mixture was continuously stirred in ice bath for another hour. The desired product was extracted with ethyl acetate (EtOAc, 200 mL). The EtOAc layer was washed with water (3×100 mL) and then dried over anhydrous sodium sulfate. The solvent was removed in vacuo to yield the crude product. The product was further purified by flash column chromatography (SiO2, 1:2 Hexane:EtOAc) to give [2-(2-hydroxy-ethoxy)-ethyl]-carbamic acid benzyl ester as a clear oil (8.07 g, 67.5% yield). 1H-NMR (CDCl3, ppm) 7.35 (m, 5H), 5.34 (b, 1H), 5.10 (s, 2H), 3.71 (m, 2H), 3.56 (m, 4H), 3.41 (m, 2H), 2.20 (b 1H),. ESMS 240.0 (M+1).

1. temperatureThe resulted solution was cooled in ice bath
2. additionAfter the addition
3. extractionThe desired product was extracted with ethyl acetate (EtOAc, 200 mL)
4. washThe EtOAc layer was washed with water (3×100 mL)
5. dry with materialdried over anhydrous sodium sulfate
6. customThe solvent was removed in vacuo
7. customto yield the crude product
8. customThe product was further purified by flash column chromatography (SiO2, 1:2 Hexane:EtOAc)

ORD record

ord-32298d0b10014a2aa40f8511e9cc147b

Source dataset

uspto-grants-2001_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06255323B1