Br[C:2]1[CH:7]=[CH:6][N:5]=[CH:4][CH:3]=1.[Br:8][C:9]1[CH:17]=[C:16](B(O)O)[C:12]2[O:13][CH2:14][CH2:15][C:11]=2[CH:10]=1.C([O-])([O-])=O.[Na+].[Na+].[NH4+].[Cl-]>COCCOC.CCO.COCCOC.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>[Br:8][C:9]1[CH:17]=[C:16]([C:2]2[CH:7]=[CH:6][N:5]=[CH:4][CH:3]=2)[C:12]2[O:13][CH2:14][CH2:15][C:11]=2[CH:10]=14-Bromopyridine or hydrochloride salt thereof was dissolved in DME under argon and Pd(Ph3P)4 (3 mol %) was added. The mixture was stirred for 10 min at 50° C. To this solution was added (commercially available) 5-bromo-2,3-dihydrobenzo[b]furan-7-boronic acid dissolved in a minimum amount of EtOH/DME 1:2 followed by 2N Na2CO3. The reaction mixture was refluxed (110° C.) under stirring for 2 h. The flask was cooled to RT, the mixture was treated with sat. aq. NH4Cl solution and extracted with CHCl3. Evaporation and purification by SiO2 gel chromatography (hexane/ethyl acetate: 4/1) gave the title compound in 76% yield.
Wird geladen…