Cl[C:2]1[CH:3]=[C:4]([CH:9]=[CH:10][N:11]=1)[C:5]([O:7][CH3:8])=[O:6].[C:12]1(B(O)O)[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1.C(=O)([O-])[O-].[K+].[K+].C(Cl)Cl>CO.O.Cl[Pd]Cl>[C:12]1([C:2]2[CH:3]=[C:4]([CH:9]=[CH:10][N:11]=2)[C:5]([O:7][CH3:8])=[O:6])[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1
Methyl 2-chloroisonicotinate (2.5 g, 14.57 mmol), phenylboronic acid (2.66 g, 21.86 mmol), potassium carbonate (3.02 g, 21.86 mmol) and PdCl2 (dppf) (0.316 g, 0.44 mmol) were mixed in methanol (15 mL) in a 20 mL microwave vial. Two drops of water were added and the vial was capped and heated at 100° C. for 10 min in a single node microwave reactor. The solids were removed by filtration and the filtrate partly evaporated to yield a dark red slurry. DCM and water were added and the phases separated. The water phase (pH 9) was extracted with DCM and the combined organic phase washed with brine, passed through a phase separator and evaporated to yield a dark red oil. The compound was purified via Biotage, SNAP 340 g KP-SIL, eluent isocratic heptane/ethyl acetate 9:1 for 2 CV, then linear gradient heptane/ethyl acetate 9:1 to 6:4 over 5 CV to give methyl 2-phenylisonicotinate (1.83 g, 58%) as a colourless oil. 1H NMR (400 MHz, cdcl3) δ 3.98 (s, 3H), 7.39-7.54 (m, 3H), 7.76 (dd, 1H), 8.01-8.09 (m, 2H), 8.29 (s, 1H), 8.82 (d, 1H). MS m/z 214 (M+H)+
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