Cl[C:2]1[CH:7]=[N:6][CH:5]=[C:4]([Cl:8])[N:3]=1.[O:9]1[CH:13]=[CH:12][CH:11]=[C:10]1B(O)O.C([O-])([O-])=O.[Na+].[Na+]>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.COCCOC>[Cl:8][C:4]1[CH:5]=[N:6][CH:7]=[C:2]([C:10]2[O:9][CH:13]=[CH:12][CH:11]=2)[N:3]=11,2-Dimethoxyethane (130 mL) was added to a mixture of tetrakis(triphenylphosphine)palladium (0) (0.93 g, 0.80 mmol) and 2,6-dichloropyrazine (2.55 g, 17.1 mmol). After 5 min of stirring at room temperature, furan-2-boronic acid (1.91 g, 17.1 mmol) followed by aqueous Na2CO3 (30 mL; 2 M) were added. The mixture was heated at reflux for 1 h [TLC monitoring by SiO2/n-hexane/ethyl acetate (90:10)]. The layers were separated and the light brownish water layer was extracted with dichloromethane (2×200 mL). The combined organic layers were dried (K2CO3), filtered and concentrated in vacuo. The brown-yellow oil obtained was purified by silica gel chromatography (18.5×4 cm) eluting with n-hexane/ethyl acetate (90:10). This furnished 1.47 g (48%) of the title compound as a light yellow solid. HRMS m/z calcd for C8H5ClN2O (M)+ 180.0090, found 180.0092. Anal. (C8H5ClN2O) C, H, N.
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