Cl[C:2]1[CH:7]=[C:6]([O:8][C:9]2[CH:10]=[N:11][C:12]([N+:15]([O-:17])=[O:16])=[CH:13][CH:14]=2)[CH:5]=[CH:4][N:3]=1.[CH3:18][C:19]1[O:20][C:21](B2OC(C)(C)C(C)(C)O2)=[CH:22][N:23]=1.C([O-])([O-])=O.[K+].[K+].CCOC(C)=O>O1CCOCC1.O.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>[CH3:18][C:19]1[O:20][C:21]([C:2]2[CH:7]=[C:6]([O:8][C:9]3[CH:10]=[N:11][C:12]([N+:15]([O-:17])=[O:16])=[CH:13][CH:14]=3)[CH:5]=[CH:4][N:3]=2)=[CH:22][N:23]=1A mixture of Example A1 (600 mg, 2.38 mmol), 2-methyl-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)oxazole (648 mg, 3.10 mmol), K2CO3 (989 mg, 7.15 mmol) and Pd(PPh3)4 (138 mg, 0.119 mmol) in dioxane (8 mL) and water (2 mL) was sparged with Ar and heated at 80° C. overnight. Additional 2-methyl-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)oxazole (100 mg) and Pd(PPh3)4 (50 mg) were added, the mixture heated at 80° C. for 5 h, then cooled to RT and treated with water and EtOAc. The solids were removed via filtration through diatomaceous earth, the layers of the filtrate separated and the organic layer was washed with brine, dried over Na2SO4, concentrated to dryness and purified via silica gel chromatography (MeOH/EtOAc) to afford 2-methyl-5-(4-((6-nitropyridin-3-yl)oxy)pyridin-2-yl)oxazole (323 mg, 45%). MS (ESI) m/z: 299.1 (M+H+).
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