Br[C:2]1[S:3][C:4]([CH3:7])=[N:5][N:6]=1.[CH:8]([C:10]1[CH:15]=[CH:14][C:13](B(O)O)=[CH:12][CH:11]=1)=[O:9].C([O-])([O-])=O.[Na+].[Na+].O>O1CCOCC1.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.CCOC(C)=O>[CH3:7][C:4]1[S:3][C:2]([C:13]2[CH:14]=[CH:15][C:10]([CH:8]=[O:9])=[CH:11][CH:12]=2)=[N:6][N:5]=1To a solution of 2-bromo-5-methyl-1,3,4-thiadiazole (2.0 g, 11.17 mmol) in dioxane (40 ml) was added 4-formylbenzeneboronic acid (3.35 g, 22.34 mmol) and 2M Na2CO3 (23 ml). This mixture was degassed with a stream of argon for 2 min. Tetrakis(triphenylphosphine)palladium (0.636 g, 0.55 mmol) was added and this mixture was heated at reflux overnight under argon. After cooling to room temperature, H2O (30 ml) and EtOAc (50 ml) were added and stirred for 5 min. The organic layer was separated and washed with brine, dried over Na2SO4 and concentrated in vacuo. Purification by chromatography (10 to 20% EtOAc/hexanes) gave 4-(5-methyl-1,3,4-thiadiazol-2-yl)benzaldehyde as a pale yellow liquid (1.16 g, 51% yield).
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