Hydrochloric Acid → 5-Chloro-2-iodopyridin-3-ol

Participants

Reaction Steps

A 20.3 g (0.157 mol) sample of 5-chloro-3-pyridinol (Aldrich Chemical Co.) and 35 g (0.33 mol) of Na2CO3 were dissolved in 220 mL of H2O. To this solution was added 39.9 g of I2, and the reaction mixture was stirred for 45 minutes. The mixture was then poured slowly into 2 N HCl, and the acidity was adjusted to pH 3. The product was collected by filtration and crystallized from EtOH/ether, affording 23.35 g of title compound: 1H NMR (CDCl3, 300 MHz) δ 5.45 (s, 1H), 8.0 (d, 1H); MS m/z: 256 (M+H)+, 273 (M+NH4)+.

Provenance & Evidence