Hydrochloric Acid → HCID 58292745, compound

Participants

Reaction Steps

To a solution of (3R)-[1-hydroxy-4-methyl-6-(pyrazin-2-yloxy)-1,3-dihydro-benzo[c][1,2]-oxaborol-3-yl]-acetic acid ethyl ester (0.90 g, 2.74 mmol, 1st peak) in methanol (15 mL) was added a solution of LiOH (0.328 g, 13.7 mmol) in water (12 mL) at 0° C. The resulting mixture was stirred at room temperature for 3 hours then acidified to pH=2 with dilute hydrochloric acid and extracted with EtOAc (2×30 mL). The organic extracts were washed with brine, dried over sodium sulfate and concentrated in vacuo. The residue was purified by silica gel flash column chromatography (DCM/MeOH/AcOH=20:1:trace) to give pure product as a white powder after lyophilization (0.681 g, 82.8%). 1HNMR (400 MHz, DMSO-d δ 9.20 (s, 1H), 8.53 (d, J=1.17 Hz, 1H), 8.35 (d, J=2.64 Hz, 1H), 8.19 (dd, J=2.63, 1.46 Hz, 1H), 7.25 (d, J=2.05 Hz, 1H), 7.10 (d, J=1.46 Hz, 1H), 5.51 (dd, J=9.51, 2.20 Hz, 1H), 3.07 (dd, J=15.52, 2.63 Hz, 1H), 2.28 (s, 3H), 2.13 (dd, 1H). MS (ESI) m/z=301 [M+H]+.

Provenance & Evidence