[CH2:1]([O:8][C:9](=[O:24])/[CH:10]=[C:11](/[NH:13][C:14]1[CH:19]=[CH:18][C:17]([CH2:20][CH2:21][OH:22])=[CH:16][C:15]=1I)\[CH3:12])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C(N(CCC)CCC)CC>CN(C=O)C.C([O-])(=O)C.[Pd+2].C([O-])(=O)C>[CH2:1]([O:8][C:9]([C:10]1[C:19]2[C:14](=[CH:15][CH:16]=[C:17]([CH2:20][CH2:21][OH:22])[CH:18]=2)[NH:13][C:11]=1[CH3:12])=[O:24])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1To a mixture of (E)-3-[4-(2-hydroxy-ethyl)-2-iodo-phenylamino}-but-2-enoic acid benzyl ester (16.6 g, 38 mmol) and tripropylamine (7.2 mL, 38 mmol) in DMF (30 mL) was added palladium acetate (170 mg, 0.76 mmol). The mixture was stirred at 120° C. for 1 hour and then partitioned between ethyl acetate and water. The organic phase was washed with water and brine, dried over Na2SO4 and filtered. The filtrate was concentrated in vacuo to give a residue, which was purified by chromatography (10%-30% ethyl acetate in hexanes) to give 3.0 g (26%) of the desired product as a white solid: mp 170-172° C.; MS(APCI+): m/z 310.4 (MH+); Anal. Calcd for C19H19N1O3.0.1H2O: C, 73.34; H, 6.22; N, 4.50. Found: C, 73.32; H, 6.37; N, 4.39.
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