[Br:1][C:2]1[CH:7]=[C:6](I)[CH:5]=[CH:4][N:3]=1.[Br-].[CH2:10]([O:12][C:13](=[O:17])[CH2:14][CH2:15][Zn+])[CH3:11].[Cl-].[NH4+].C(=O)(O)[O-].[Na+]>C1COCC1.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:1][C:2]1[N:3]=[CH:4][C:5]([CH2:15][CH2:14][C:13]([O:12][CH2:10][CH3:11])=[O:17])=[CH:6][CH:7]=1Palladium tetrakis (1.64 g, 1.41 mmol) was added to a solution of 2-bromo-4-iodopyridine (4.00 g, 14.1 mmol) in THF (28.2 ml) under an argon atmosphere. The mixture was cooled to 0° C., 3-ethoxy-3-oxopropylzinc bromide (36.6 mL, 18.3 mmol) was slowly added to the reaction mixture and stirred for 1 hour. The mixture was then allowed to warm to room temperature overnight. An aqueous ammonium chloride was added to the reaction mixture and stirred for 5 minutes. pH was then adjusted to ˜8 with aqueous sodium bicarbonate and product was extracted with ethyl acetate (3×). The combined organic layers were dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel chromatography (ethyl acetate/hexanes) to afford ethyl 3-(6-bromopyridin-3-yl)propanoate. MS ESI calc'd for C10H13BrNO2 [M+H]+ 258 and 260. found 258 and 260.
読み込み中…
