Br[C:2]1[CH:10]=[C:9]2[C:5]([CH:6]=[N:7][NH:8]2)=[CH:4][CH:3]=1.[C:11]([O:15][C:16]([N:18]1[CH2:23][CH:22]=[C:21](B2OC(C)(C)C(C)(C)O2)[CH2:20][CH2:19]1)=[O:17])([CH3:14])([CH3:13])[CH3:12].C([O-])([O-])=O.[K+].[K+].C([O-])([O-])=O.[Na+].[Na+]>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.O1CCOCC1>[C:11]([O:15][C:16]([N:18]1[CH2:19][CH:20]=[C:21]([C:2]2[CH:10]=[C:9]3[C:5]([CH:6]=[N:7][NH:8]3)=[CH:4][CH:3]=2)[CH2:22][CH2:23]1)=[O:17])([CH3:14])([CH3:12])[CH3:13]To a mixture of 6-bromoindazole (2.0 g, 10.2 mmol), 4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-3,6-dihydro-2H-pyridine-1-carboxylic acid tert-butyl ester (3.5 g, 11.2 mmol) and Pd(PPh3)4 (1.2 g, 1.0 mmol) under N2 were added 1,4-dioxane (80 mL), followed by addition of K2CO3 (2 M in H2O, 20 mL, 40 mmol). The resulting mixture was heated at 110° C. for 16 h, then cooled to room temperature. The resulting mixture was then treated with saturated Na2CO3 aqueous solution. The resulting mixture was extracted with EtOAc (3×). The combined extracts were washed with brine and then dried over Na2SO4. The resulting mixture was filtered, concentrated under reduced pressure, and the residue purified by flash chromatography on silica-gel (gradient eluent heptane to 60% EtOAc in heptane) to yield 4-(1H-indazol-6-yl)-3,6-dihydro-2H-pyridine-1-carboxylic acid tert-butyl ester as brownish foam solid.
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