[CH3:1][O:2][C:3]([C:5]1[C:10]([NH2:11])=[N:9][C:8](Cl)=[CH:7][N:6]=1)=[O:4].[Cl-].[Li+].C([Sn](CCCC)(CCCC)/[CH:20]=[CH:21]\[O:22][CH2:23][CH3:24])CCC.[NH4+].[Cl-]>CN(C=O)C.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>[CH3:1][O:2][C:3]([C:5]1[C:10]([NH2:11])=[N:9][C:8](/[CH:20]=[CH:21]\[O:22][CH2:23][CH3:24])=[CH:7][N:6]=1)=[O:4]A mixture of 3-amino-5-chloro-pyrazine-2-carboxylic acid methyl ester [28643-16-5] (2 g, 10.66 mmol), lithium chloride (1.582 g, 37.3 mmol), Pd(PPh3)2Cl2 (0.748 g, 1.066 mmol) and tributyl-((Z)-2-ethoxy-vinyl)-stannane (6.42 ml, 19.19 mmol) in DMF (104 ml) under argon was heated at 80° C. bath temperature for 1.5 h. A saturated. aq. NH4Cl was added and the mixture was extracted with MTBE, then once with EtOAc/THF 3/1. The combined organic layer was washed with brine, dried with Na2SO4, filtered and concentrated under reduced pressure. The residue was purified by chromatography on silica gel (cyclohexane to cyclohexane/EtOAc 1:9) to provide the title compound as yellow oil (1.96 g).
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