2,4-Difluorophenylhydrazine hydrochloride → HCID 118431621, compound

HRID 2207907Notes

Reaction equation

[CH3:1][O:2][C:3](=[O:14])[C:4](=O)[CH:5]=[CH:6][C:7]1[S:8][C:9]([Br:12])=[CH:10][CH:11]=1.Cl.[F:16][C:17]1[CH:22]=[C:21]([F:23])[CH:20]=[CH:19][C:18]=1[NH:24][NH2:25]>C(O)(=O)C>[CH3:1][O:2][C:3]([C:4]1[CH2:5][CH:6]([C:7]2[S:8][C:9]([Br:12])=[CH:10][CH:11]=2)[N:24]([C:18]2[CH:19]=[CH:20][C:21]([F:23])=[CH:22][C:17]=2[F:16])[N:25]=1)=[O:14]

Participants

Conditions

Temperature: 125 °C

Procedure

4-(5-Bromo-thiophen-2-yl)-2-oxo-3-butenoic acid methyl ester (17.0 g, 61.8 mmol) prepared in Step 2 and 2,4-difluorophenylhydrazine hydrochloride (12.3 g, 68.0 mmol) were added to acetic acid (200.0 mL). The reaction mixture was stirred at 125° C. for 2 hours, concentrated under reduced pressure, and then ethyl acetate was added thereto. The mixture was washed with a saturated solution of sodium hydrogen carbonate, dried on anhydrous magnesium sulfate, and then concentrated under reduced pressure to give a yellow liquid residue. The resulting residue was purified by silica gel column chromatography (eluent: ethyl acetate/n-hexane=1/20) to give 15.1 g of the titled compound as a yellow solid.

Workup

concentrationconcentrated under reduced pressure
additionethyl acetate was added
washThe mixture was washed with a saturated solution of sodium hydrogen carbonate
dry with materialdried on anhydrous magnesium sulfate
concentrationconcentrated under reduced pressure
customto give a yellow liquid residue
customThe resulting residue was purified by silica gel column chromatography (eluent: ethyl acetate/n-hexane=1/20)

Sources & evidence

ORD record: ord-ca00f81fdb1148a99958d6ea271c0e9e
Source dataset: uspto-grants-2016_06
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US09376420B2

Reaction notes

Loading…