Iodine → 5-Bromo-3-(1,4,5,6-tetrahydro-2-pyrimidinylthio)-indole hydriodide

Participants

Reaction Steps

A solution of 19.6 g of 5-bromo-indole in 50 ml of methanol is added to a stirred solution of 50 g potassium iodine and 25.4 g of iodine in 150 ml of water at room temperature. The mixture is further treated with a solution of 11.6 g of 1,4,5,6-tetrahydro-2-pyrimidinethiol in 270 ml of warm methanol. The reaction mixture is then stirred at room temperature for 2 hours, filtered and the filtrate is concentrated to one-fifth of the original volume and cooled. A crystalline precipitate is formed. This is filtered and recrystallised from a mixture of methanol, ethylacetate and ether to yield 5-bromo-3-(1,4,5,6-tetrahydro-2-pyrimidinylthio)-indole hydriodide which melts at 241°-242°.

Provenance & Evidence