[CH3:1][O:2][C:3](=[O:11])[C:4]1[CH:9]=[C:8]([OH:10])[CH:7]=[N:6][CH:5]=1.[C:12]1(B(O)O)[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1.C(Cl)Cl.CCN(CC)CC>CCOC(C)=O.C([O-])(=O)C.[Cu+2].C([O-])(=O)C>[CH3:1][O:2][C:3](=[O:11])[C:4]1[CH:9]=[C:8]([O:10][C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)[CH:7]=[N:6][CH:5]=1
0.31 g (2 mmol) of 5-hydroxy-nicotinic acid methyl ester, 0.73 g (4 mmol) of copper acetate, ˜1 g of 4 Å molecular sieves and 0.85 g (7 mmol) of phenylboronic acid were combined in a flask charged with 20 mL of DCM and 2.0 mL (14 mmol) of Et3N. This reaction slurry was stirred overnight at r.t. The reaction mixture was then diluted with 200 mL of EtOAc and washed 3 times with 10% K2CO3. The organic layer was then dried with Na2SO4, evaporated and purified by flash column chromatography (EtOAc/hexanes=1:2) to give 5-phenoxy-nicotinic acid methyl ester, which was subsequently hydrolyzed according to general procedure B to give 5-phenoxy-nicotinic acid and used in the next step without further purification.
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