Sodium borohydride → HCID 118431940, compound

HRID 2207908Notes

Reaction equation

C[O:2][C:3]([C:5]1[CH2:9][CH:8]([C:10]2[S:11][C:12]([Br:15])=[CH:13][CH:14]=2)[N:7]([C:16]2[CH:21]=[CH:20][C:19]([F:22])=[CH:18][C:17]=2[F:23])[N:6]=1)=O.[BH4-].[Na+]>CO>[Br:15][C:12]1[S:11][C:10]([CH:8]2[N:7]([C:16]3[CH:21]=[CH:20][C:19]([F:22])=[CH:18][C:17]=3[F:23])[N:6]=[C:5]([CH2:3][OH:2])[CH2:9]2)=[CH:14][CH:13]=1

Participants

Conditions

Temperature: 80 °C

Procedure

To a solution of 5-(5-bromo-thiophen-2-yl)-1-(2,4-difluoro-phenyl)-4,5-dihydro-1H-pyrazole-3-carboxylic acid methyl ester (15.1 g, 37.6 mmol) prepared in Step 3 in methanol (125.3 mL), was slowly added sodium borohydride (6.4 g, 169.2 mmol) at 0° C. The reaction mixture was stirred at 80° C. for 18 hours, concentrated under reduced pressure, acidified by a 1N hydrochloric acid solution, and then extracted with dichloromethane. The extract was washed with brine, 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=1/2) to give 12.9 g of the titled compound as a yellow liquid.

Workup

customat 0° C
concentrationconcentrated under reduced pressure
extractionextracted with dichloromethane
washThe extract was washed with brine
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=1/2)

Sources & evidence

ORD record: ord-ee7cb99ea8f24b068821892fb902ba66
Source dataset: uspto-grants-2016_06
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US09376420B2

Reaction notes

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