Methanesulfonic Acid → 6-Bromo-8-fluoro-3,4-dihydroisoquinolin-1(2H)-one

Temperature

0 °C

To a mixture of 144d (10.35 g, 45.19 mmol) in DCM (75 mL) was added methanesulfonic acid (52.73 mL, 70.92 g, 737.90 mmol) at 0° C., followed by sodium azide (5.88 g, 90.44 mmol) in several portions. See FIG. 3. The reaction mixture was stirred at 0° C. for 2 h, and 20% aq. NaOH solution (40 mL) was added. The reaction mixture was stirred for 30 min, and the aqueous phase was extracted with DCM (400 mL×3). The combined organic layers were washed with saturated brine (200 mL×2), dried with anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel chromatography (PE/EA=10/1 to 2/1) to afford the 5.2 g (47.1%) of 6-bromo-8-fluoro-3,4-dihydroisoquinolin-1(2H)-one 144e. 1H NMR (400 MHz, CDCl3) δ 7.22-7.25 (d, J=10.4 Hz, 1H), 7.20 (s, 1H), 6.94 (s, 1H), 3.46-3.53 (m, 2H), 2.88-2.97 (m, 2H); MS-ESI [M+H]+=243.9/245.9.

1. stirringThe reaction mixture was stirred for 30 min
2. extractionthe aqueous phase was extracted with DCM (400 mL×3)
3. washThe combined organic layers were washed with saturated brine (200 mL×2)
4. dry with materialdried with anhydrous sodium sulfate
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified by silica gel chromatography (PE/EA=10/1 to 2/1)

ORD record

ord-922b6ab8737c44349c9276a50e6f3ac0

Source dataset

uspto-grants-2016_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09326985B2