C([O-])([O-])=O.[Na+].[Na+].[NH2:7][C:8]1[CH:13]=[CH:12][C:11](Br)=[CH:10][N:9]=1.[Cl:15][C:16]1[CH:21]=[CH:20][C:19](OB(O)O)=[CH:18][CH:17]=1>O1CCOCC1.CO.CCOC(C)=O.O>[Cl:15][C:16]1[CH:21]=[CH:20][C:19]([C:11]2[CH:12]=[CH:13][C:8]([NH2:7])=[N:9][CH:10]=2)=[CH:18][CH:17]=1300 mL (600 mmol) of a 2 M Na2CO3 solution and 3.45 g (3.0 mmol) tetrakis-triphenylphosphane-palladium are added successively to a solution of 53.5 g (300 mmol) 2-amino-5-bromopyridine and 50.0 g (313 mmol) 4-chlorophenylboric acid in 1.0 L 1,4-dioxane and 250 mL methanol under argon. The reaction mixture is stirred for 2.5 h at 110° C. The solvent is eliminated i.vac., the residue is taken up in EtOAc and water. The organic phase is dried over Na2SO4 and the solvent is eliminated i.vac. Further purification is carried out by column chromatography on silica gel (gradient: DCM to DCM/MeOH 20:1).
Wird geladen…
