N-bromobutanimide → HCID 83913406, compound

A solution of (1-methyl-3-phenyl-1H-pyrazol-5-yl)methanol (1b) (340 mg, 1.81 mmol) and N-bromosuccinimide (338 mg, 1.90 mmol) in acetonitrile (30 mL) was stirred at room temperature for 1 hour. The reaction mixture was concentrated in vacuo. Water (10 mL) was added and the aqueous layer was extracted with ethyl acetate (2×12 mL). The organic layer was dried over sodium sulfate and concentrated in vacuo. The residue was taken in dichloromethane (5 mL) and manganese dioxide (1.57 g, 18.06 mmol) was added. The reaction mixture was stirred at room temperature for 40 hours, filtered over Celite®, and the filtrate was concentrated in vacuo. The residue was dissolved in a minimum of dichloromethane and purified thought a pad of silice, (cyclohexane/ethyl acetate 80/20), to provide 4-bromo-1-methyl-3-phenyl-1H-pyrazole-5-carbaldehyde (1c) (304 mg, 1.15 mmol, 63%).

1. concentrationThe reaction mixture was concentrated in vacuo
2. additionWater (10 mL) was added
3. extractionthe aqueous layer was extracted with ethyl acetate (2×12 mL)
4. dry with materialThe organic layer was dried over sodium sulfate
5. concentrationconcentrated in vacuo
6. filtrationfiltered over Celite®
7. concentrationthe filtrate was concentrated in vacuo
8. dissolutionThe residue was dissolved in a minimum of dichloromethane
9. custompurified

ORD record

ord-76df916a95ee420094d8cb4bf9d3b281

Source dataset

uspto-grants-2016_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09260395B2