Sulfuric Acid → 6-(Methylthio)pyridin-3-OL

Participants

Reaction Steps

A solution of 5.5 ml of concentrated sulfuric acid and 8 ml of water is added to 1.9 g (13.55 mM) of 6-(methylthio)-3-pyridinamine. The reaction medium is brought to −6° C. and a solution of 1.59 g (23.03 mM) of sodium nitrite in 3 ml of water is added dropwise without exceeding 0° C. The mixture is stirred for 1 hour 30 min between 0° C. and −4° C. and then refluxed for 1 hour. The cooled reaction medium is poured in the presence of sodium bicarbonate and the mixture is then extracted with ethyl acetate. The organic phase is concentrated under reduced pressure and the residue is then chromatographed on silica gel (dichloromethane/ethyl acetate, 90/10; v/v) to give the expected product in the form of a white powder with a yield of 60%.

Provenance & Evidence