Methyl iodide → 4-(1-Methoxy-1-methyl-ethyl)-benzoic acid methyl ester

Beteiligte Stoffe

Reaktionsschritte

439 mg of sodium hydride (60% in mineral oil) were suspended in 10 ml DMF and a solution of 1.64 g of 4-(1-hydroxy-1-methyl-ethyl)-benzoic acid methyl ester (8.4 mmol) in 10 ml DMF was added at 0° C. The mixture was allowed to warm to rt and was stirred for 1 h at this temperature before 0.79 ml of methyl iodide (12.7 mmol) were added. After 17 h additional 338 mg of sodium hydride (60% in mineral oil) and 0.53 ml methyl iodide (8.4 mmol) were added and stirring was continued for 20 h. Then saturated ammonium chloride solution was added and the mixture was extracted with EtOAc. The combined organic layers were washed with water and brine, dried with magnesium sulfate, filtered and the solvent was evaporated. Chromatographic purification (silica gel; c-hexane/EtOAc 9:1 to 4:1) of the remaining residue yielded 661 mg (38%) of 4-(1-methoxy-1-methyl-ethyl)-benzoic acid methyl ester as a colorless liquid. 1H NMR (CDCl3, 300 MHz): δ 1.54 (s, 6H), 3.09 (s, 3H), 3.92 (s, 3H), 7.48 (d, J=9 Hz, 1H), 8.02 (d, J=9 Hz, 1H).

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