Reaction Steps
To a degassed refluxing solution of 3-{[(2-iodo-phenyl)-(3-phenyl-propynoyl)-amino]-methyl}-benzoic acid methyl ester (100 mg, 0.2 mmol) and Ni(PPh3)2I2 (16 mg, 0.02 mmol) in CH2Cl2 (8 ml) was added 3-methylbutylzinc bromide (151 mg, 0.7 mmol) in CH2Cl2 (1 ml). The reaction was stirred at 40° C. for 6 h and then the solution was cooled to room temperature. The resultant solution was diluted with ethyl acetate (50 ml). The organic layer was washed with aqueous HCl solution (4%, 10 ml), brine (3×10 ml). The aqueous layer was back-extracted with ethyl acetate (3×10 ml). The combined organic layer was dried over anhydrous sodium sulfate. After filtration, the solvent was removed under reduced pressure and the residue was purified by column chromatography on silica gel, eluting with petrol ether-ethyl acetate, to give 3-{3-[4-methyl-1-phenyl-pent-(Z)-ylidene]-2-oxo-2,3-dihydro-indol-1-ylmethyl}-benzoic acid methyl ester (24 mg, 28%) as light yellow solid. 1H NMR (300 Hz, CDCl3): δppm 0.88 (d, 6H), 1.43-1.55 (m, 2H), 1.68-1.72 (m, 1H), 2.93-2.99 (m, 2H), 3.91 (s, 3H), 4.89 (s, 2H), 6.64 (d, 1H), 7.05 (t, 1H), 7.15 (t, 1H), 7.28-7.38 (m, 4H), 7.40-7.47 (m, 3H), 7.62 (d, 1H), 7.91 (d, 1H), 7.95 (s, 1H); and 3-{3-[4-methyl-1-phenyl-pent-(E)-ylidene]-2-oxo-2,3-dihydro-indol-1-ylmethyl}-benzoic acid methyl ester (29 mg, 33%) as light yellow solid. 1H NMR (300 Hz, CDCl3): δ ppm 0.88 (d, 6H), 1.36-1.44 (m, 2H), 1.64-1.68 (m, 1H), 3.33-3.38 (m, 2H), 3.91 (s, 3H), 5.04 (s, 2H), 6.01 (d, 1H), 6.58-6.61 (m, 2H), 6.96-7.02 (t, 1H), 7.26-7.29 (m, 2H), 7.37 (t, 2H), 7.43-7.52 (m, 3H), 7.93 (d, 1H), 8.03 (s, 1H).