Methanol → Methyl 3-hydroxy-2-methylbenzoate

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Reaction Conditions

Reaction Steps

3-Hydroxy-2-methylbenzoic acid (250 g, 1.32 mole) was added to methanol (2500 mL, 10×) in a jacketed bottom drop three neck flask under nitrogen. Sulfuric acid (48.3 g, 0.49 mole) was added to the above solution. The mixture was heated to 60° C. and stirred for 8 to 17 hours. Once conversion was >98%, the mixture was atmospherically distilled to 3× volume. The residue was cooled to 20° C. and slowly added to water (500 mL, 2×) over at least 30 minutes. Seeds (2 g, 0.01×) were added and the mixture was agitated at 20° C. for at least 1 hour. Water (1500 mL, 6×) was added at 20° C. over at least 3 hours and the mixture was agitated at 20° C. for at least one additional hour. The solid was filtered, and washed three times with 9:1 water:methanol (500 mL, 2× each) until pH≧3. The solid was dried under vacuum at 35 to 45° C. until KF≦0.1% to give methyl 3-hydroxy-2-methylbenzoate (235.3 g, 86% yield);

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