Hydrochloric Acid → Methyl 4-iodo-2-[N-(N-butylaminocarbonyl)aminosulfonyl]benzoate

Participants

Reaction Conditions

Reaction Steps

34.1 g (0.1 mol) of the sulfonamide of the formula (IV) from Example 1 and 14.7 g of K2CO3 (0.105 mol) are admixed with 10.6 g of n-butyl isocyanate (98% pure) (0.105 mol) in 250 ml of chlorobenzene, and the mixture is kept at 55 to 60° C. for 2 hours. The mixture is then stirred at 90° C. for 8.5 h. The mixture is cooled to room temperature and initially 200 ml of water and then 2n of hydrochloric acid are added until the pH has reached 1-2. The organic phase is separated off and washed free of acid using four times 50 ml of water. The solvent is removed under reduced pressure, and 43.8 g of the desired compound of the formula (I) (99.3% of theory) of melting point 128 to 130° C. remain.

Provenance & Evidence