Dimethyl Sulfate → (1-Methoxyphenylethylidene)malononitrile

Beteiligte Stoffe

Reaktionsschritte

To a suspension of 60% NaH/mineral oil dispersion (2.9 g, 74.7 mmol) in THF (50 ml) was added dropwise (1-hydroxyphenylethylidene)malononitrile (13.8 g, 74.7 mmol) in THF (75 ml) over 25 minutes, followed by dimethylsulfate (7.1 ml, 74.7 mmol) in THF (50 ml) over 20 minutes. The reaction mixture was stirred at room temperature for 30 minutes, then at reflux for 4 hours. 0.5 equivalents of 60% sodium hydride and dimethylsulfate were added and the reaction mixture was stirred at room temperature for 24 hours. The solvent was removed in vacuo, the residue was partitioned between ether and water, the organic layer was separated and the aqueous layer was extracted with ether (3×150 ml). The combined organic layers were dried over anhydrous MgSO4 and solvent was removed in vacuo. The residue was purified by column chromatography on silica eluting with ethyl acetate/hexanes (1/1) to afford 8.4 g (56%) of (1-methoxyphenylethylidene)malononitrile as an amber liquid.

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