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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1612147Generated: October 27, 2026

Phosphorus oxybromide → 3-(2,4-Dichlorophenyl)-2,5-dimethylpyrazine

https://huagongshe.com/reaction/1612147

Reaction equation

Participants

RoleNameHCIDCharge
ReactantPhosphorus oxybromideHCID 24613—
ReactantProton spongeHCID 88675—
Reactant3-(2,4-Dichlorophenyl)-2,5-dimethylpyrazine 1-oxideHCID 22147291—
SolventDichloromethaneHCID 6344—
Product3-(2,4-Dichlorophenyl)-2,5-dimethylpyrazineHCID 2214735138%
Product2-Bromo-5-(2,4-dichlorophenyl)-3,6-dimethylpyrazineHCID 2214742535%

Reaction Steps

POBr3 (573 mg) was added to the solution of 3-(2,4-dichlorophenyl)-2,5-dimethylpyrazine 1-oxide (270 mg) and proton sponge (197 mg) in CH2Cl2 at 0° C. The reaction mixture was warmed to r.t. for 10 h. The reaction mixture was washed with 1N HCl, NaHCO3 and brine, dried (MgSO4), filtered and concentrated. Flash chromatography (silica gel Heptane:EtOAC 100:1) gave the title compound (110 mg, 35%) and 3-(2,4-dichlorophenyl)-2,5-dimethylpyrazine (100 mg, 38%). 1H NMR (CDCl3) δ 2.40, 2.71, 7.28, 7.40, 7.54; MS (ESI+) for C12H9Cl2N2Br1 m/z 333.0 (M+H)+.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS06992087B2
Source datasetuspto-grants-2006_01
ORD IDord-f7c2ab92c2df4d19ba9ee92d04b3a6a7
Source noteuspto-grants-2006_01