[Br:1][C:2]1[CH:3]=[CH:4][CH:5]=[C:6]2[C:11]=1[N:10]=[C:9](Cl)[CH:8]=[N:7]2.[CH3:13][C:14]([OH:18])([C:16]#[CH:17])[CH3:15].CCN(CC)CC>[Cu]I.Cl[Pd](Cl)([P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)[P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1>[Br:1][C:2]1[CH:3]=[CH:4][CH:5]=[C:6]2[C:11]=1[N:10]=[C:9]([C:17]#[C:16][C:14]([CH3:15])([OH:18])[CH3:13])[CH:8]=[N:7]2A microwave tube is charged with 200 mg (0.821 mmol) of 8-Bromo-2-chloro-quinoxaline, 159 μl (1.64 mmol) of 2-Methyl-but-3-yn-2-ol, 231 μl (1.64 mmol) of Et3N, 6.26 mg (0.0329 mmol) of CuI and 11.8 mg (0.0164 mmol) of Pd(PPh3)2Cl2. After several cycles of vacuum/purge with argon, 5 ml of n-BuOH are added. The reaction mixture is then stirred at RT for 30 min. The reaction mixture is poured onto a solution of NaHCO3 and diluted with EtOAc and the phases are separated. The organic phase is washed several times with de-ionized water and the aqueous layer re-extracted with EtOAc. The combined organic layers are washed with brine, dried over Na2SO4, filtered and the filtrate is concentrated in vacuo. The residue is dissolved in CH2Cl2 and purified by chromatography (silicagel, hexane:EtOAc=1:1) to afford the title compound as a brown oil, Rt=1.026 min (Acquity HPLC BEH C18, 2.1×50 mm, 1.7 micron, detection 215 nM, 0.1 min 2% CH3CN in H2O, 2% to 100% CH3CN in H2O in 1.5 min, 0.4 min 100% CH3CN+0.1% TFA, flow rate 1.0 ml/min); MS: 291 (M+1, 79Br)+.
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