[C:1]1([CH3:13])[CH:6]=[CH:5][C:4]([C:7]2([C:10]([OH:12])=[O:11])[CH2:9][CH2:8]2)=[CH:3][CH:2]=1.O.[C:15]1(C)C=CC(S(O)(=O)=O)=CC=1>CO>[C:1]1([CH3:13])[CH:2]=[CH:3][C:4]([C:7]2([C:10]([O:12][CH3:15])=[O:11])[CH2:9][CH2:8]2)=[CH:5][CH:6]=1To a stirred solution of 1-(p-tolyl)cyclopropanecarboxylic acid (6 g, 34.05 mmol) in methanol (48 mL), was added para-toluenesulphonic acid monohydrate (0.648 g, 3.405 mmol). The reaction was stirred at 75° C. for 16 hours. The mixture was concentrated under reduced pressure, and the residue partitioned between ethyl acetate and saturated aqueous sodium bicarbonate solution. The organic layer was washed with saturated aqueous sodium bicarbonate solution (×2), brine and dried (magnesium sulfate), filtered, and concentrated under reduced pressure to afford the title compound as an orange oil (6.279 g, 97%). The material was used directly in the next step with no further purification.
Wird geladen…
