Br[C:2]1[CH:3]=[CH:4][C:5]2[N:6]([N:8]=[CH:9][N:10]=2)[CH:7]=1.[CH3:11]C([O-])=O.[K+].C([O-])([O-])=O.[K+].[K+].Cl[C:23]1[C:31]([CH2:32][CH3:33])=[CH:30][C:26]([C:27]([O-:29])=[O:28])=[C:25]([O:34][CH3:35])[N:24]=1>C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.Cl[Pd]Cl.[Fe+2].O>[N:10]1[CH:9]=[N:8][N:6]2[CH:7]=[C:2]([C:23]3[C:31]([CH2:32][CH3:33])=[CH:30][C:26]([C:27]([O:29][CH3:11])=[O:28])=[C:25]([O:34][CH3:35])[N:24]=3)[CH:3]=[CH:4][C:5]=126-bromo-[1,2,4]triazolo[1,5-a]pyridine (0.107 g, 0.54 mmol), bis(pinacolato) diborate (0.170 g, 0.67 mmol), Pd(dppf)Cl2 (15.8 mg, 0.02 mmol, 4 mol %), and KOAc (0.160 g, 1.63 mmol) were mixed together in a heat-gun dried vial. The vial was vacuumed and backfilled with argon before dioxane (1.6 mL) was added. The mixture was heated at 130° C. for ˜1 h until complete consumption of the starting bromide was observed. The reaction mixture was cooled to room temperature before H2O (0.20 mL), K2CO3 (0.220 g, 1.59 mmol) and 6-chloro-5-ethyl-2-methoxynicotinate (0.150 g, 0.65 mmol) were added. The reaction vial was resealed under argon and the mixture was heated at 120° C. for 3 h and then cooled to room temperature. Water (5 mL) was added to the reaction mixture and the product was extracted with DCM (3×5 mL). The combined organics were washed with NaCl (aqueous saturated, 5 mL) and dried over Na2SO4. After concentration of the solvent the residue was purified by column chromatography (EtOAc/hexanes, 0-100% gradient). Upon concentration of the desired fractions, the residue was treated with H2O (5 mL) and stirred vigorously for 30 min, the solid was then filtered and washed with H2O. Upon drying methyl 6-([1,2,4]triazolo[1,5-a]pyridin-6-yl)-5-ethyl-2-methoxynicotinate (0.115 g, 69%) was obtained as pale yellow solid.
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