62638-06-6

1. cyclohexane-1,3-dicarboxylic acid (10.32 g, 60 mmol) was dissolved in methanol (130 mL). 2. Concentrated sulfuric acid (2.5 mL) was added as a catalyst and the reaction mixture was heated to reflux and stirred for 16 hours. 3. Upon completion of the reaction, the reaction mixture was concentrated under reduced pressure to remove most of the methanol. 4. The residue was adjusted to pH 7 with saturated aqueous sodium bicarbonate. 5. The aqueous phase was extracted with ethyl acetate (200 mL × 3) and the organic layers were combined. 6. 6. The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to give dimethyl 1,3-cyclohexanedioate as a colorless oil (12 g, 100% yield). 7. The product was analyzed by 1H NMR. 7. The product was characterized by 1H NMR (400 MHz, DMSO-d6) and mass spectrometry (ESI): 1H NMR δ 3.61 (s, 6H), 2.69-1.13 (m, 10H); MS (ESI) m/e [M + 1] 201.1.

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