1-(4-Methoxyphenyl)cyclopropane-1-carboxylic acid → Methyl 1-(4-methoxyphenyl)-cyclopropanecarboxylate

Beteiligte Stoffe

Reaktionsschritte

To a solution of 1-(4-methoxy-phenyl)-cyclopropanecarboxylic acid (50.0 g, 0.26 mol) in MeOH (500 mL) was added toluene-4-sulfonic acid monohydrate (2.5 g, 13 mmol) at room temperature. The reaction mixture was heated at reflux for 20 hours. MeOH was removed by evaporation under vacuum and EtOAc (200 mL) was added. The organic layer was washed with sat. aq. NaHCO3 (100 mL) and brine, dried over anhydrous Na2SO4 and evaporated under vacuum to give 1-(4-methoxy-phenyl)-cyclopropanecarboxylic acid methyl ester (53.5 g, 99%). 1H NMR (CDCl3, 400 MHz) δ 7.25-7.27 (m, 2H), 6.85 (d, J=8.8 Hz, 2H), 3.80 (s, 3H), 3.62 (s, 3H), 1.58 (m, 2H), 1.15 (m, 2H).

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