Br[C:2]1[C:3]([CH:8]=[O:9])=[N:4][CH:5]=[CH:6][CH:7]=1.[CH3:10][C:11]1[CH:16]=[CH:15][C:14](B(O)O)=[CH:13][CH:12]=1.C([O-])([O-])=O.[Na+].[Na+]>COCCOC.C1COCC1.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>[C:11]1([CH3:10])[CH:16]=[CH:15][C:14]([C:2]2[C:3]([CH:8]=[O:9])=[N:4][CH:5]=[CH:6][CH:7]=2)=[CH:13][CH:12]=1To a stirred degassed solution of 3-bromo-2-pyridinecarboxaldehyde (198 mg, 1.06 mmol) and 4-methylbenzene boronic acid (152 mg, 1.12 mmol) in DME/THF (3.5 mL, 2.5:1) were added a 2 M Na2CO3 solution (0.9 mL) and Pd(PPh3)4 (63 mg, 0.055 mmol). The reaction mixture was flushed with Ar and maintained under Ar while being heated at 90° C. overnight. The mixture was then cooled and diluted with EtOAc (40 mL) and brine (30 mL). The organic layer was washed with brine (1×30 mL), dried (Na2SO4), filtered and concentrated. Purification of the resultant oil by column chromatography with silica gel (Hexanes/EtOAc, 2:1) afforded 3-p-tolyl-pyridine-2-carbaldehyde (161 mg, 77%) as a yellow oil. 1H NMR (CDCl3) δ 2.43 (s, 3H), 7.25-7.28 (m, 4H), 7.53 (dd, 1H, J=9, 6 Hz), 7.79 (dd, 1H, J=9, 1 Hz), 8.80 (dd, J=3, 1 Hz), 10.09 (s, 1H).
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