Benzenesulfonyl chloride → 2-Benzenesulfonylamino-3-iodo-5-methylthiopyridine

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-amino-3-iodo-5-methylthiopyridine (7.63 g) in pyridine (30 ml), benzenesulfonyl chloride (7.9 ml) was added at 15 to 30° C. under nitrogen atmosphere and the mixture was stirred at 60° C. for 15 hours. The reaction solution was then poured into a saturated aqueous sodium hydrogencarbonate solution, extracted with dichloromethane, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. A solution of the resulting crude bis(benzenesulfonyl) product in a mixture of methanol/dioxane (1:1, 200 ml) was added a 1N aqueous potassium hydroxide solution (64 ml) at 15 to 30° C. and the mixture was stirred at 60° C. for 1 hour. The reaction solution was then poured into a saturated aqueous sodium hydrogencarbonate solution, extracted with dichloromethane, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The resulting residue was separated using silica gel column chromatography (methanol:chloroform=1:50) to obtain 6.4 g (56%) of the desired product as a white powder.

Provenance & Evidence