Ethyl Acetate → (S)-2-[4-(2-fluoro-3-vinyl-phenoxy)-2-oxo-2,5-dihydro-pyrrol-1-yl]-4-methyl-pentanoic acid ethyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a mixture of (S)-2-[4-(3-bromo-2-fluoro-phenoxy)-2-oxo-2,5-dihydro-pyrrol-1-yl]-4-methyl-pentanoic acid ethyl ester (prepared as in Example 128, 0.624 g, 1.51 mmol), tetrakis(triphenylphosphine)palladium(0) (0.200 g, 0.17 mmol) in N,N-dimethylformamide (7 mL) was added tributyl(vinyl)tin (0.652 g, 2.05 mmol) and the resulting mixture stirred at 80° C. for 14 h. The mixture was taken up in ethyl acetate and dilute hydrochloric acid and separated. The organic phase was washed with, saturated sodium bicarbonate solution, a saturated sodium chloride solution and dried over sodium sulfate. The mixture was filtered, evaporated and the residue purified by ISCO flash chromatography (Teledyne Isco RediSep Flash Column 50 g, 10% to 50% ethyl acetate/hexanes) which afforded (S)-2-[4-(2-fluoro-3-vinyl-phenoxy)-2-oxo-2,5-dihydro-pyrrol-1-yl]-4-methyl-pentanoic acid ethyl ester (0.400 g, 73%) as a clear oil.

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