Hydrochloric Acid → 3-(Cyclopentyloxy)-4-methoxybenzoic acid

Participants

Reaction Conditions

Reaction Steps

A stirred saturated aqueous solution of potassium permanganate (100 mL) is treated with 3-cyclopentyloxy-4-methoxybenzaldehyde (7.4 g; that is prepared as described hereinbefore in Reference Example 1) and sodium carbonate (3.4 g) and the mixture is stirred at 50° C. for 1 hour, and then cooled to room temperature. The reaction mixture is acidified by treatment with concentrated hydrochloric acid and then it is treated with aqueous sodium bisulfite solution until a colorless solution is obtained. The reaction mixture is extracted with dichloromethane (2×100 mL) and the organic extracts are dried over magnesium sulfate and concentrated. The resulting residue is recrystallized from diethyl ether, to give 3-cyclopentyloxy-4-methoxybenzoic acid (4.78 g) in the form of white crystals. [NMR(CDCl3): 1.7(s,2H),1.8-2.2 (m,6H),3.95(s,3H),4.85(s,1H),6.9(bs,1H)7.6(bs,1H), 7.8(s,1H),9.8(s,1H); Elemental analysis: C,65.6; H,6.8%; Calculated: C,66.1; H,6.8%].

Provenance & Evidence