Acetic Acid → 27314-97-2

Participants

Reaction Conditions

Reaction Steps

To a stirred mixture containing 1.000 kg (7.347 moles) of benzofuroxan and 2.237 kg (14.694 moles) of DBU was added a solution containing 618 g (14.694 moles) of cyanamide in 380 ml of acetonitrile while maintaining the temperature below 25° C. After stirring for 48 hours at 20-25° C. the reaction mixture was dilute with 6.620 liters of acetonitrile and cooled below 15° C. To the cooled mixture was added 882 g (14.694 moles) of acetic acid while maintaining the temperature below 15° C. After stirring overnight at 5-10° C. the precipitated product was collected by filtration and washed with acetonitrile (2×2 liters). The resulting solid was suspended in 2 liters of water, stirred about 30 minutes until a homogeneous suspension was obtained, and then filtered. The collected solid was resuspended in 2 liters of water, stirred for 20-30 minutes and filtered. The solid collected was dried to constant weight under vacuum at 50-55° C. to give 506.6 g of tirapazamine.

Provenance & Evidence