Phenylacetic Acid → 4-Benzylpyridazine

Temperature

80 °C

A solution of pyridazine (2.2 g, 27.5 mmol) and 2-phenylacetic acid (18.7 g, 137.5 mmol), AgNO3 (1.4 g, 8.25 mmol) in 2N H2SO4 (27.7 ml) was heated to 60-70° C. under stirring, then, a solution of (NH4)2S2O8 (18.6 g, 82.5 mmol) in 80 ml of water was added within 20 minutes, After heating to 70-90° C. for 1.5 hour, the reaction solution was cooled to room temperature and extracted with DCM (2×100 ml), the combined organic layers were washed with 2NH. SO4 (3×70 ml), then, the combined aqueous layer was made alkaline with 50% NaOH and extracted with DCM (3×80 ml), dried over Na2SO4 and concentrated to get the crude product, which was purified by column chromatography on silica gel (petroleum Ether: EtOAc=2:1) to afford 4-benzylpyridazine (1.0 g, yield: 22%). 1H NMR (CDCl3 400 MHz): δ9.09 (s, 1H), 9.06 (d, J=5.2 Hz, 1H), 7.40-7.28 (m, 3H), 7.25-7.20 (m, 1H), 7.18 (d, J=7.2 Hz, 2H), 4.0 (s, 2H).

1. temperaturethe reaction solution was cooled to room temperature
2. extractionextracted with DCM (2×100 ml)
3. washthe combined organic layers were washed with 2NH
4. extractionextracted with DCM (3×80 ml)
5. dry with materialdried over Na2SO4
6. concentrationconcentrated
7. customto get the crude product, which
8. customwas purified by column chromatography on silica gel (petroleum Ether: EtOAc=2:1)

ORD record

ord-9b8d12fcce19404eb64e2ad67a19c82e

Source dataset

uspto-grants-2015_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09102591B2