Hydrochloric Acid → HCID 56837987, compound

To a solution of 5 (400 mg, 1.35 mmol) in 4 mL of absolute ethanol was added anhydrous 1M HCl in EtOAc (4 mL, 4 mmol). The reaction was stirred at room temperature for 16 h. The mixture was then concentrated and azeotroped with acetonitrile (3×10 mL) to give a sticky solid. Ether (10 mL) was added to the azeotroped sticky solid and the resulting precipitate was filtered. The filtered solid was rinsed with additional ether (5 mL) and dried to give ethyl 2-((3R,6S)-2-hydroxy-3-(2-(thiophen-2-yl)acetamido)-1,2-oxaborinan-6-yl)acetate 65 (300 mg, 0.92 mmol, 68.5% yield). 1H NMR (CD3OD) δ ppm 0.98-1.09 (q, J=14 Hz, 1H), 1.23-1.26 (t, J=7 Hz, 3H), 1.49-1.54 (dd, J=14 Hz, J=3 Hz, 1H), 1.57-1.64 (dt, J=11 Hz, J=2 Hz, 1H), 1.72-1.78 (brd, J=14 Hz, 1H), 2.24-2.28 (dd, J=15 Hz, J=6 Hz, 1H), 2.34-2.39 (dd, J=15 Hz, J=8 Hz, 1H), 2.63 (brs, 1H), 3.99 (s, 2H), 4.07-4.13 (q, J=4 Hz, 3H), 6.99-7.01 (t, J=4 Hz, 1H), 7.05-7.06 (d, J=3 Hz, 1H), 7.35-7.36 (dd, J=5 Hz, J=1.3 Hz, 1H); ESIMS found for C14H20BNO5S m/z 308.1 (M−H2O)+.

1. concentrationThe mixture was then concentrated
2. customazeotroped with acetonitrile (3×10 mL)
3. customto give a sticky solid
4. filtrationthe resulting precipitate was filtered
5. washThe filtered solid was rinsed with additional ether (5 mL)
6. customdried

ORD record

ord-7acf0fd91a6b4fb7bfb698af7bb6d2f1

Source dataset

uspto-grants-2016_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09296763B2