3964-57-6

Methyl 3-Chloro-4-hydroxybenzoate is a reagent in the preparation of alkylidene hydrazides as human glucagon receptor antagonists for the treatment of hyperglycemia and diabetes.

1. Sulfuric acid (3 mL, 56.3 mmol) was added to a solution of 3-chloro-4-hydroxybenzoic acid (1.0 g, 5.8 mmol) in methanol (30 mL). 2. The reaction mixture was stirred at 60 °C for 12 hours. 3. Upon completion of the reaction, the mixture was cooled to room temperature and the methanol was removed under vacuum. 4. The residue was partitioned between saturated sodium bicarbonate solution and ethyl acetate (3 x 30 mL). 5. The organic layer was separated, dried over anhydrous sodium sulfate, filtered and concentrated under vacuum to afford methyl 3-chloro-4-hydroxybenzoate (0.9 g, 83% yield) as a white solid. 6. The product was characterized by ESI-MS and NMR: ESI-MS m/z calculated 186.5, measured 187.5 (M + 1)+; retention time: 1.17 min (3 min run). ,2.2H, 1H), 7.06 (d, J = 8.8 Hz, 1H) and 3.90 (s, 3H).

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