Br[C:2]1[CH:7]=[CH:6][C:5]([CH3:8])=[CH:4][N:3]=1.C([Sn](CCCC)(CCCC)[C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][N:15]=1)CCC>C1(C)C=CC=CC=1.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>[CH3:8][C:5]1[C:4]([C:14]2[CH:19]=[CH:18][CH:17]=[CH:16][N:15]=2)=[N:3][CH:2]=[CH:7][CH:6]=1A mixture of 2-bromo-5-methylpyridine (5.0 g, 29 mmol), 2-tributylstannylpyridine (10 g, 27 mmol) and Pd(PPh3)4 (2.0 g, 1.7 mmol) in dry toluene (250 mL) was stirred for 48 h at 110° C. The reaction mixture was filtered over Celite and evaporated under reduced pressure. The residue was dissolved in EtOAc and washed with saturated aqueous NaHCO3 solution, and the organic layer was dried over MgSO4 and concentrated under reduced pressure. Flash column chromatography (0.5% MeOH in CH2Cl2) afforded methyl-2,2′-bipyridine (3.5 g, 75%) as a colorless oil. 1H-NMR (500 MHz, CDCl3): 2.47 (s, 3H), 7.35 (dd, 1H), 7.70 (dd, 1H), 7.87 (m, 1H), 8.36 (d, 1H), 8.43 (d, 1H), 8.58 (d, 1H), 8.74 (dd, 1H).
Wird geladen…
