[Mg].Br[C:3]1[CH:8]=[CH:7][C:6]([O:9][CH3:10])=[CH:5][C:4]=1[O:11][CH3:12].Br[C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][N:15]=1.[Cl-]>O1CCCC1>[CH3:12][O:11][C:4]1[CH:5]=[C:6]([O:9][CH3:10])[CH:7]=[CH:8][C:3]=1[C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][N:15]=1A stirred suspension of magnesium (8.11 g) in dry tetrahydrofuran (100 mL) is heated, and then treated with a solution of 1-bromo-2,4-dimethoxybenzene (48 mL) in tetrahydrofuran (100 mL) at such a rate as to maintain reflux. The resulting solution is then cooled and added, dropwise, to a solution of 2-bromopyridine (50.3 g) and bis-triphenylphosphinepalladium(II) chloride (3.5 g) in tetrahydrofuran (100 mL) at reflux, and the mixture is maintained at reflux for 6 hours. The solution is then evaporated and the residue is dissolved in ethyl acetate, washed with water, dried and evaporated to give a dark oil. This is subjected to flash chromatography on silica gel, eluting with a mixture of pentane and ethyl acetate (2:1 v/v) to give 2-(2,4-dimethoxyphenyl)pyridine (28 g) in the form of an oil. [NMR(CDCl3):- 3.84(3H,s),3.86(3H,s), 6.55(1H,s),6.6(1H,d),7.2(1H,m),7.7(1H,t),7.77 (1H,d),7.8(1H,d),8.7(1H,d)].
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