[NH2:1][C:2]1[CH:7]=[N:6][C:5](Br)=[CH:4][N:3]=1.[O:9]1[CH:13]=[CH:12][C:11](B(O)O)=[CH:10]1.C(=O)([O-])[O-].[Na+].[Na+]>COCCOC.C(O)C.C(OCC)(=O)C.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[O:9]1[CH:13]=[CH:12][C:11]([C:5]2[N:6]=[CH:7][C:2]([NH2:1])=[N:3][CH:4]=2)=[CH:10]1A mixture of 2-amino-5-bromopyrazine (300 mg, 1.724 mmol), tetrakis(triphenylphosphine)palladium(0) (340 mg, 0.294 mmol), furan-3-boronic acid acid (300 mg, 2.681 mmol), and a saturated aqueous sodium carbonate solution (2 mL) in ethylene glycol dimethyl ether (5 mL) and ethanol (5 mL) was heated under reflux for 45 min. The reaction mixture was cooled, diluted with ethyl acetate, and washed with water and a saturated aqueous sodium chloride solution. The organic layer was dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo. Biotage chromatography (FLASH 40M, Silica, 2/3 hexanes/ethyl acetate to ethyl acetate) afforded 5-furan-3-yl-pyrazin-2-ylamine (256.9 mg, 92.5%) as a yellow solid: LRMS for C8H7N3O (M+H)+ at m/z=162.
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