Back
HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1504793Generated: October 31, 2026

Bromine → 3-bromo-4H,5H,6H-pyrrolo[1,2-b]pyrazole

https://huagongshe.com/reaction/1504793

Reaction equation

Participants

RoleNameHCIDCharge
ReactantBromineHCID 24408—
ReactantSodium BicarbonateHCID 516892—
ReactantSodium AcetateHCID 517045—
Reactant5,6-Dihydro-4H-pyrrolo(1,2-b)pyrazoleHCID 11073365—
SolventAcetic AcidHCID 176—
Product3-bromo-4H,5H,6H-pyrrolo[1,2-b]pyrazoleHCID 15287071—

Reaction Steps

To a solution of 5,6-dihydro-4H-pyrrolo[1,2-b]pyrazole (47.2 g, 437 mmol) and sodium acetate (36.2 g, 440 mmol) in acetic acid (750 mL) at 0° C. was added bromine (22.4 mL, 435 mmol). After 10 minutes, the reaction mixture was neutralized with saturated aqueous sodium bicarbonate and extracted with ethyl acetate (5×200 mL). The organic layers were combined, dried over magnesium sulfate, and concentrated under reduced pressure to afford 3-bromo-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazole.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS09216173B2
Source datasetuspto-grants-2015_12
ORD IDord-47f2f55f28374be6a754d04da8a619a6
Source noteuspto-grants-2015_12