p-Toluenesulfonic acid → Methyl 1-phenylcyclopropane-1-carboxylate

Reaction equation

[C:1]1([C:7]2([C:10]([OH:12])=[O:11])[CH2:9][CH2:8]2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[CH3:13]C1C=CC(S(O)(=O)=O)=CC=1.CCOC(C)=O>CO>[C:1]1([C:7]2([C:10]([O:12][CH3:13])=[O:11])[CH2:9][CH2:8]2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1

Participants

Procedure

To a solution of 1-phenylcyclopropanecarboxylic acid (25 g, 0.15 mol) in CH3OH (200 mL) was added TsOH (3 g, 0.1 mol) at room temperature. The mixture was refluxed overnight. The solvent was evaporated under reduced pressure to give crude product, which was dissolved into EtOAc. The EtOAc layer washed with aq. sat. NaHCO3. The organic layer was dried over anhydrous Na2SO4 and evaporated under reduced pressure to give methyl 1-phenylcyclopropanecarboxylate (26 g, 96%), which was used directly in the next step. 1H NMR (400 MHz, CDCl3) δ 7.37-7.26 (m, 5H), 3.63 (s, 3H), 1.63-1.60 (m, 2H), 1.22-1.19 (m, 2H).