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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1159807Generated: October 27, 2026

Chloropyrazine → 4-pyrazin-2-yl-1H-indole

https://huagongshe.com/reaction/1159807

Reaction equation

Participants

RoleNameHCIDCharge
ReactantChloropyrazineHCID 73277—
ReactantSodium BicarbonateHCID 516892—
ReactantPotassium AcetateHCID 517044—
Reactant4-BromoindoleHCID 676494—
ReactantBis(pinacolato)diboraneHCID 2733548—
CatalystPalladium ChlorideHCID 24290—
SolventWaterHCID 962—
SolventDichloromethaneHCID 6344—
Solvent1,2-DimethoxyethaneHCID 8071—
Product4-pyrazin-2-yl-1H-indoleHCID 68717665—

Reaction Conditions

Temperature125 °C

Reaction Steps

4-Bromoindole (0.1 g, 0.51 mmol), bis(pinacolato)diboron (0.172 g, 0.77 mmol), potassium acetate (0.075 g, 0.765 mmol) and PdCl2 (0.022 g, 0.031 mmol) were dissolved in DME (3 mL) and heated in the microwave for 900 seconds at 125° C. The reaction was cooled and NaHCO3 (0.129 g, 1.53 mmol), 2-chloropyrazine (0.087 g, 0.77 mmol) tetrakis(triphenylphosphine)palladium (0.0295 g, 0.026 mmol), H2O (1 mL) and DME (1 mL) were added and the mixture was stirred in the microwave for 900 seconds at 120° C. The mixture was diluted with dichloromethane and filtered. The filtrate was washed with water (2×), dried (MgSO4) and evaporated. The crude product was purified by flash chromatography using 2.5% to 5% CH3OH in dichloromethane. Not pure, purified by flash chromatography using hexane/EtOAc 7:3 to 1:1 as the eluent. Yield: 93 mg (47%). White solid. MS (electronspray; [M+H]+) m/z 196.3.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS07812017B2
Source datasetuspto-grants-2010_10
ORD IDord-fe6fd4cded794428afabcbe8cad33f60
Source noteuspto-grants-2010_10