Phosphorus tribromide → HCID 86694683, compound

Temperature

-10 °C

To a solution of 2-(3-amino-1H-pyrazol-5-yl)ethanol (13 g, 102.2 mmol) in DCM (200 mL) was added PBr3 (83 g, 306.7 mmol). The reaction mixture was heated under reflux for 3 h and then cooled to −10° C. and carefully quenched with aq satd Na2CO3 (200 mL). The resulting mixture was extracted with DCM (3×200 mL), and the Na2CO3 (200 mL). The resulting mixture was extracted with DCM (3×200 mL) combined organic layers were washed with brine, dried over anhydrous Na2SO4, and then concentrated in vacuo to give 5-(2-bromoethyl)-1H-pyrazol-3-amine (9.3 g, 48%) as a yellow solid.

1. temperatureThe reaction mixture was heated
2. temperatureunder reflux for 3 h
3. customcarefully quenched with aq satd Na2CO3 (200 mL)
4. extractionThe resulting mixture was extracted with DCM (3×200 mL)
5. extractionThe resulting mixture was extracted with DCM (3×200 mL)
6. washwere washed with brine
7. dry with materialdried over anhydrous Na2SO4
8. concentrationconcentrated in vacuo

ORD record

ord-75f4049113a74f33b77e4586a196400c

Source dataset

uspto-grants-2014_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08637537B2