Sodium hydride → (4-Bromo-benzyl)-(3-fluoro-propyl)-carbamic acid tert-butyl ester

Temperature

55 °C

To a solution of 117 (286 mg, 1.0 mmol) in anhydrous DMF (3.0 mL) was added sodium hydride (NaH, 60% oil dispersion, 48.0 mg, 1.2 mmol, 1.2 equiv) at 0° C. The resulting mixture was stirred at 0° C. for 30 min before 1-bromo-3-fluoropropane 118 (170 mg, 1.2 mmol, 1.2 equiv) was added. The reaction mixture was subsequently warmed to 50-60° C. and stirred for 24 hours. The reaction mixture was then quenched with water (10 mL), and the resulting aqueous solution was extracted with EtOAc (2×20 mL). The combined organic extracts were washed with water (10 mL) and saturated aqueous NaCl (10 mL), dried over MgSO4 and concentrated in vacuo. The residue was purified by column chromatography (10-15% EtOAc/hexane gradient elution) to afford the desired (4-bromo-benzyl)-(3-fluoro-propyl)-carbamic acid tert-butyl ester 115 (158 mg, 46% yield) as a colorless oil.

1. additionwas added
2. customThe reaction mixture was then quenched with water (10 mL)
3. extractionthe resulting aqueous solution was extracted with EtOAc (2×20 mL)
4. washThe combined organic extracts were washed with water (10 mL) and saturated aqueous NaCl (10 mL)
5. dry with materialdried over MgSO4
6. concentrationconcentrated in vacuo
7. customThe residue was purified by column chromatography (10-15% EtOAc/hexane gradient elution)

ORD record

ord-e0718d6d5f1744989b1ccb80e7ac55d3

Source dataset

uspto-grants-2014_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08895741B2