Lithium borohydride → Benzyl (1-(hydroxymethyl)cyclopropyl)carbamate

To a stirred solution of ethyl 1-(benzyloxycarbonylamino)cyclopropanecarboxylate (8.7 g, 33.0 mmol) in 50 mL of THF was slowly added at room temperature LiBH4 (2.26 g, 103.76 mmol) and the mixture was stirred at room temperature for 16 hours. The reaction mixture was cooled to 0° C. and quenched by adding a 50% HOAc solution (10 mL). The reaction mixture was partitioned between 70 mL of water and 70 mL of diethyl ether. The organic phase was washed with saturated aqueous NaHCO3 solution (15 mL), brine (10 mL) and dried over anhydrous sodium sulfate. The drying agent was removed by filtration and the filtrate was evaporated at 40° C. under reduced pressure to give a crude product, which was purified by column chromatography (silica gel, 200-300 mesh, eluting with a mixture of petroleum ether and ethyl acetate (1:1, v/v) to give benzyl 1-(hydroxymethyl)cyclopropylcarbamate (6.36 g, 87.1%) as a white solid. MS: (M+H)+=222.1; 1H NMR (300 MHz, CDCl3): δ 7.46-7.35 (m, 5H), 5.38 (brs, 1H), 5.19 (s, 2H), 3.71 (s, 2H), 0.96 (s, 4H).

1. temperatureThe reaction mixture was cooled to 0° C.
2. customquenched
3. additionby adding a 50% HOAc solution (10 mL)
4. customThe reaction mixture was partitioned between 70 mL of water and 70 mL of diethyl ether
5. washThe organic phase was washed with saturated aqueous NaHCO3 solution (15 mL), brine (10 mL)
6. dry with materialdried over anhydrous sodium sulfate
7. customThe drying agent was removed by filtration
8. customthe filtrate was evaporated at 40° C. under reduced pressure
9. customto give a crude product, which
10. customwas purified by column chromatography (silica gel, 200-300 mesh
11. washeluting with a mixture of petroleum ether and ethyl acetate (1:1

ORD record

ord-f39f7fc310804f5fb47120cae4488742

Source dataset

uspto-grants-2014_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08658646B2