Sodium hydride → methyl 3-(4-nitrophenyl)-1H-pyrrole-2-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a suspension of 1.62 g (40.63 mmol) of 60% sodium hydride in mineral oil in 100 cm3 of tetrahydrofuran is added dropwise over 25 minutes, at a temperature in the region of 20° C. under an argon atmosphere, a mixture of 5.87 g (19.35 mmol) of 1-[(E)-2-(4-methylphenyl)sulfonylvinyl]-4-nitrobenzene and 3.7 cm3 (38.7 mmol) of methyl isocyanoacetate dissolved in 150 cm3 of tetrahydrofuran. After stirring for 5 hours at a temperature in the region of 20° C., the reaction mixture is taken up in a mixture of 100 cm3 of water and 200 cm3 of ethyl acetate. The organic phase is washed with twice 100 cm3 of water and 150 cm3 of saturated aqueous sodium chloride solution, dried over anhydrous magnesium sulfate, filtered and concentrated to dryness under reduced pressure (2.7 kPa) to give 5.3 g of a brown oil, which is purified by flash chromatography [eluent: dichloromethane]. After concentrating the fractions under reduced pressure, 2.12 g of methyl 3-(4-nitrophenyl)-1H-pyrrole-2-carboxylate are obtained in the form of a yellow solid; M.W.=246, IE: m/z=246 M+, m/z=214 [M-CH3OH]+.

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