Sodium Sulfite → 5-Hydroxy-6-methylpyridine-2-carboxylic acid

Participants

Reaction Steps

A mixture of 5-methoxy-6-methyl-pyridine-2-carboxylic acid (53 mg, 0.32 mmol) and hydrogen iodide (2.06 mL of 57% w/v, 9.20 mmol) was heated at reflux for 4 hours. The reaction was cooled to room temperature before water (3 mL) was added. Na2SO3 was added to decolorize the reaction. The aqueous layer was decanted and the pH was adjusted to 3-4 using 2 M HCl. The product was extracted using ethyl acetate (7×5 mL). The organic layer was dried over sodium sulfate, filtered and the solvent was evaporated under reduced pressure to yield 5-hydroxy-6-methylpicolinic acid. ESI-MS m/z calc. 153.0, found 154.1 (M+1)+; Retention time: 0.21 minutes (3 min run).

Provenance & Evidence