Triethylamine → (E)-tert-Butyl 2-(2-methoxyethoxymethyl)-3-(p-toluenesulphonyl)acrylate

Beteiligte Stoffe

Reaktionsschritte

To a solution of p-toluenesulphonyl iodide (19.39 g, 68.7 mmol) in dichloromethane (50 mL) at room temperature under a nitrogen atmosphere was added tert-butyl 2-(2-methoxyethoxymethyl)acrylate (9.91 g, 45.8 mmol). The mixture was stirred at room temperature for 16 hours, cooled to 0° C. and triethylamine (12.7 mL, 91.6 mmol) added dropwise. The reaction was stirred at 0° C. for 0.5 hours and at room temperature for 4 hours, diluted with distilled water (100 mL) and the layers separated. The aqueous layer was further extracted with dichloromethane (25 mL) and the combined organic extracts were washed with 1.0M aqueous hydrochloric acid solution (100 mL), 5% aqueous sodium thiosulphate solution (25 mL) and distilled water (50 mL). The dichloromethane phase was concentrated under reduced pressure to give a brown oil (17.48 g, quantitative). The crude product was purified by chromatography on silica by gradient elution with hexane/ethyl acetate mixtues to give, after combination and evaporation of appropriate fractions, the title compound as a pale yellow oil (16.2 g, 95%) which crystallised on standing, m.pt.=40°-41° C., Rf =0.3 (silica; hexane/ethyl acetate, 2:1).

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