Br[C:2]1[CH:3]=[CH:4][C:5]([C:8]([O:10][C:11]([CH3:14])([CH3:13])[CH3:12])=[O:9])=[N:6][CH:7]=1.CC1(C)C(C)(C)OB(B2OC(C)(C)C(C)(C)O2)O1.CC([O-])=O.[K+].C([O-])([O-])=O.[K+].[K+].Cl[C:45]1[CH:50]=[N:49][CH:48]=[CH:47][N:46]=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].C(Cl)Cl.C1COCC1>[C:11]([O:10][C:8](=[O:9])[C:5]1[CH:4]=[CH:3][C:2]([C:45]2[CH:50]=[N:49][CH:48]=[CH:47][N:46]=2)=[CH:7][N:6]=1)([CH3:14])([CH3:13])[CH3:12]The 250 mL flask was charged with tert-butyl 5-bromopicolinate 34h-4 (12.9 g, 50 mmol), 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi(1,3,2-dioxaborolane) (13.9 g, 55 mmol), KOAc (9.8 g, 100 mmol), PdCl2(dppf)-CH2Cl2 adduct (0.408 g, 0.5 mmol) and THF (80 mL). The flask was sealed under nitrogen and the mixture was stirred at 80° C. for 24 hours. After completion of the reaction, it was cooled to room temperature and filtered through Celite. The filtrate was taken in 500 mL 4-necked RB flask and charged with aqueous K2CO3 solution (13.8 g in 100 ml Of water), 2-chloropyrazine (6.8 g, 60 mmol), and PdCl2(dppf)-CH2Cl2 adduct (0.204 g, 0.25 mmol). The reaction mixture was stirred at 64° C. for 2 h under nitrogen, cooled to room temperature and filtered through Celite. The filtrate was diluted with i-PrOAc (100 mL) and the aqueous layer separated. The organic layer was washed with water (2×100 mL), concentrated to ˜20 mL of volume and diluted with heptane (200 mL). The solid was collected by filtration, washed with heptane (50 mL), and dried at 40° C. to obtain 34h-1 as a pale yellow solid.
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