To a 25 mL round bottom flask was added 2-bromo-5-(methylthio)-1,3,4-thiadiazole (0.40 g, 1.9 mmol) (prepared as described in WO 97/30981, isoquinolin-6-ylboronic acid (0.39 g, 2.3 mmol) (prepared as described in US Patent Publication No. US 2007/0173506), Pd(PPh3)4 (0.11 g, 0.095 mmol), 2.4 mL of a 2 M Na2CO3 aqueous solution and 2 mL of DME. The reaction was heated at reflux for 16 hours. The reaction mixture was concentrated, and the residue was purified by column chromatography on silica gel (eluting with a gradient from 0 to 70% EtOAc in hexanes) to provide 6-(5-(methylthio)-1,3,4-thiadiazol-2-yl)isoquinoline (0.29 g, 59%) as a yellow solid. LCMS (M+H) 260 calc. for C12H10N3S2 260.0.
