Butyl isocyanate → HCID 13364390, compound

Participants

Reaction Steps

To a mixture of 5.0 g of4-ethoxycarbonyl-1-methylpyrazole-5-sulfonamide(Reference example 25), 4.45 g of dry potassium carbonate and 50 ml of acetone was added 2.13 g of n-butyl isocyanate at room temperature, and the mixture was stirred under reflux for 3 hours. After the reaction, acetone was evaporated under reduced pressure, and ice-water was added to the residue, followed by filtration of the insolubles. The filtrate was made acidic with hydrochloric acid and the crystals precipitated were filtered, washed with water and dried to give 5.1 g of N-(n-butylcarbamoyl)-4-ethoxycarbonyl-1-methylpyrazole-5-sulfonamide melting at 117°-119° C. Then, this product was added into 120 ml of dry toluene, and 9.1 g of phosgene was passed into the mixture under reflux, followed further by refluxing for 1.5 hours. After completion of the reaction, the reaction mixture was concentrated under reduced pressure to obtain crude sulfonyl isocyanate.

Provenance & Evidence