Diethyl Ether → tert-butyl N-hydroxycarbamate

Temperature

0 °C

To a -78° C. solution of 547 mg (3.44 mmol) of N-Boc glycinal (20) in 17 mL of diethyl ether was added 5.16 mL (10.3 mmol, 3 equiv) of isobutylmagnesium chloride (2.0M in diethyl ether). After five minutes, the solution was warmed to 0° C. and stirred for 24 h. The reaction mixture was then diluted with 300 mL of ethyl acetate, washed with 1N aqueous sodium bisulfate, dried over magnesium sulfate and concentrated. Purification by flash chromatography (20×150 mm silica gel, 30% ethyl acetate/hexane) gave 291 mg (39%) of the title compound as a clear oil: Rf 0.20 (30% ethyl acetate/hexane); 1H NMR (300 MHz, CDCl3) δ5.19 (br t, J=5.4 Hz, 1H), 3.69 (br m, 1H), 3.24-3.19 (br m, 1H), 3.09 (br s, 1H), 2.92 (br pent, J=6.4 Hz, 1H), 1.72 (hept, J=6.4 Hz, 1H), 1.45-1.29 (m, 1H), 1.39 (s, 9H), 1.15 (ddd, J=4.8, 8.7, 13.4 Hz, 1H), 0.86 (t, J=6.3 Hz, 6H); MS(FAB) 218 (M+1), 162.

1. washwashed with 1N aqueous sodium bisulfate
2. dry with materialdried over magnesium sulfate
3. concentrationconcentrated
4. customPurification by flash chromatography (20×150 mm silica gel, 30% ethyl acetate/hexane)

ORD record

ord-2d23b0b4ab464098a4b7f50e943bdf92

Source dataset

uspto-grants-1993_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05254682