[NH2:1][C:2]1[C:7](I)=[C:6]([Cl:9])[N:5]=[C:4]([C:10]([O:12][CH3:13])=[O:11])[C:3]=1[Cl:14].[CH3:15][Sn](C)(C)C>ClCCCl.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>[NH2:1][C:2]1[C:7]([CH3:15])=[C:6]([Cl:9])[N:5]=[C:4]([C:10]([O:12][CH3:13])=[O:11])[C:3]=1[Cl:14]A mixture of methyl 4-amino-3,6-dichloro-5-iodopicolinate (8.1 g, 23.4 mmol), tetramethylstannane (8.35 g, 46.7 mmol), and bis(triphenylphosphine)palladium(II) chloride (2.5 g, 3.5 mmol) in 1,2-dichloroethane (40 mL) was irradiated in a Biotage Initiator microwave at 120° C. for 30 min, with external IR-sensor temperature monitoring from the side. The reaction mixture was loaded directly onto a silica gel cartridge and purified by flash chromatography (silica gel, 0-50% ethyl acetate/hexanes) to provide the title compound as an orange solid (4.53 g, 19.27 mmol, 83%): mp 133-136° C.; 1H NMR (400 MHz, CDCl3) δ 4.92 (s, 2H), 3.96 (s, 3H), 2.29 (s, 3H); 13C NMR (101 MHz, CDCl3) δ 164.34, 150.24, 148.69, 143.94, 117.01, 114.60, 53.02, 14.40; ESIMS m/z 236 ([M+H]+), 234 ([M−H]−).
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