[CH3:1][O:2][C:3](=[O:13])[C:4]1[C:9]([O:10][CH3:11])=[CH:8][C:7](Cl)=[N:6][CH:5]=1.[CH2:14]([C:16]1[CH:21]=[CH:20][CH:19]=[C:18]([CH2:22][CH3:23])[C:17]=1B(O)O)[CH3:15].C([O-])([O-])=O.[Na+].[Na+].CCCCCC>C1(C)C=CC=CC=1.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>[CH3:1][O:2][C:3](=[O:13])[C:4]1[C:9]([O:10][CH3:11])=[CH:8][C:7]([C:17]2[C:18]([CH2:22][CH3:23])=[CH:19][CH:20]=[CH:21][C:16]=2[CH2:14][CH3:15])=[N:6][CH:5]=1A mixture of 6-chloro-4-methoxy-nicotinic acid methyl ester (4.0 g, 19.8 mmol), 2,6-diethylphenyl boronic acid (7.0 g, 39.3 mmol), Na2CO3 (2M in H2O, 39 mL) and Pd(PPh3)4 (2.0 g, 1.7 mmol) in toluene (200 mL) is heated overnight at 80° C. under argon. On cooling, hexane (200 mL) is added and the organic layer separated. The organic layer is washed with 1N NaOH and water, dried (Na2SO4) and concentrated. The residue is purified by silica gel column (hexane/EtOAc 4:1) to give 6-(2,6-diethyl-phenyl)-4-methoxy-nicotinic acid methyl ester. 1H NMR (CDCl3) 8.99 (s, 1H), 7.30 (m, 1H), 7.15 (d, 2H), 6.89 (s, 1H), 3.95 (s, 3H), 3.94 (s, 3H), 2.34 (m, 4H), 1.06 (t, 6H).
Wird geladen…