Hydrochloric Acid → HCID 58292673, compound

Participants

Reaction Steps

To a solution [6-(3-tert-butoxycarbonylamino-propoxy)-1-hydroxy-4-methyl-1,3-dihydro-benzo[c][1,2]oxaborol-3-yl]-acetic acid ethyl ester (0.445 g, 1.09 mmol) in THF (14 mL) was added a solution of LiOH (0.229 g, 5.44 mmol) in water (5 mL) at 0° C. The resulting mixture was stirred at room temperature for 3 hours then acidified to pH=2 with 6M HCl and extracted with EtOAc (3×25 mL). The organic extracts were washed with brine, dried (MgSO4), filtered and concentrated in vacuo. The residue was purified by silica gel flash column chromatography (20% EtOAc/hexane) to give [6-(3-tert-butoxycarbonylamino-propoxy)-1-hydroxy-4-methyl-1,3-dihydro-benzo[c][1,2]oxaborol-3-yl]-acetic acid (0.450 g, 80%). 1H NMR (400 MHz, DMSO-d6) δ ppm 9.08 (s, 1H), 7.00 (d, J=1.90 Hz, 1H), 6.87 (br. s., 1H), 6.81 (s, 1H), 5.41 (dd, J=9.52, 2.22 Hz, 1H), 3.93 (t, J=6.19 Hz, 2H), 3.06 (t, J=6.34 Hz, 2H), 3.00 (dd, J=15.55, 2.54 Hz, 1H), 2.23 (s, 3H), 2.03 (dd, J=15.39, 9.68 Hz, 1H), 1.80 (t, J=6.66 Hz, 2H), 1.35 (s, 9H).

Provenance & Evidence