Br[C:2]1[N:11]=[CH:10][CH:9]=[CH:8][C:3]=1[C:4]([O:6][CH3:7])=[O:5].[Cl:12][C:13]1[CH:18]=[CH:17][CH:16]=[C:15](B2OC(C)(C)C(C)(C)O2)[N:14]=1.C([O-])([O-])=O.[K+].[K+].O>O1CCOCC1.Cl[Pd](Cl)([P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)[P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1>[Cl:12][C:13]1[N:14]=[C:15]([C:2]2[C:3]([C:4]([O:6][CH3:7])=[O:5])=[CH:8][CH:9]=[CH:10][N:11]=2)[CH:16]=[CH:17][CH:18]=1
0.49 g (0.70 mmol) of (Ph3P)2PdCl2 is added under argan to a solution of 3.0 g (13.9 mmol) of methyl 2-bromonicotinate in 10 ml of dioxane and the mixture is stirred for 30 min at room temperature. Thereafter, 3.33 g (13.78 mmol) of 2-chloro-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine, 5.76 g (41.68 mmol) of K2CO3 and 11 ml of H2O are added in succession to the mixture, and the mixture is stirred for 6 hours under reflux and subsequently allowed to stand overnight at room temperature (RT). For work-up, the reaction mixture is poured into 150 ml of H2O and extracted repeatedly with CH2Cl2. The combined organic phases are dried over Na2SO4 and subsequently concentrated. The crude product thus obtained is purified by chromatography on silica gel using heptane/ethyl acetate (7:3) as the mobile phase. This gives 2.50 g (72%) of product as a colorless oil; 1H NMR (CDCl3) δ 8.70 (dd, 1H), 8.15 (dd, 1H), 7.95 (dd, 1H), 7.80 (dd, 1H), 7.40 (dd, 1H), 7.37 (dd, 1H), 3.90 (s, 3H, COOMe).
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