Dimethylamine, hydrochloride → HCID 19825004, compound

Participants

Reaction Steps

To a mixture of 3.6 g of 2-[4-(2-oxopropoxy)phenyl]-2,3,4,4a-tetrahydro-5H-(1)benzothiopyrano[4,3-c]pyridazin-3-one, 3.3 g of dimethylamine hydrochloride and 50 ml of ethanol is added dropwise 20 ml of a solution of 1 g of sodium cyanoboron hydride in 20 ml of ethanol while stirring under heating and reflux over 1 hour. The mixture is stirred under heating and reflux for further 4 hours. After the completion of the reaction, the solvent is distilled off, and water and dilute hydrochloric acid are added to the residue. After the mixture is left standing still for 30 minutes, it is neutralized with potassium carbonate and extracted with chloroform. The extract is dried over magnesium sulfate, and the solvent is distilled off. The residue is purified by silica gel column chromatography (chloroform:methanol =10:1 ) and then converted into the fumarate in acetone, which is recrystallized from ethanol to give 3.4 g of 2-[4-(2-dimethylaminopropoxy)phenyl]-2,3,4,4a-tetrahydro-5H-(1)benzothiopyrano[4,3-c]pyridazin-3-one.fumarate as white crystals, m.p. 171°-173° C.

Provenance & Evidence