5-Hydroxyindole-2-carboxylic acid → methyl 5-hydroxy-1H-indole-2-carboxylate

Beteiligte Stoffe

Reaktionsschritte

A 4 N hydrogen chloride-methanol solution (80 mL) of 5-hydroxyindole-2-carboxylic acid (3.0 g) was heated overnight under reflux. The solvent was evaporated off from the reaction liquid under reduced pressure, aqueous saturated sodium hydrogencarbonate solution was added to the resulting residue, and extracted with ethyl acetate. The organic layer was dried with anhydrous magnesium sulfate, and the solvent was evaporated off under reduced pressure. The resulting residue was purified through silica gel column chromatography (hexane/ethyl acetate=4/1 to 3/2) to obtain methyl 5-hydroxy-1H-indole-2-carboxylate (2.3 g) as a pale brown solid.

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