Citric Acid → 361343-20-6

Participants

Reaction Conditions

Reaction Steps

To an appropriate speck-free flask maintained under a nitrogen atmosphere, add Z-4-(3,4-dichlorophenyl)-2-[2-(4-methylpiperazin-1-yl)-benzylidene]-thiomorpholin-3-one (23.2 g, 51.8 mmol), citric acid (10.4 g, 54.4 mmol), and 603 mL of a speck-free aqueous isopropanol solution (1:1 v/v). A slurry formed and was heated to reflux (83-84° C.) affording a solution at approximately 70° C. The solution was further heated at reflux for 0.5 hours and then filtered hot. The filtrate was slowly cooled to 50-55° C. over 0.45 hours and then maintained at 50-55° C. for 1 hour. The slurry was cooled further to 0-5° C., granulated for 1-2 hours, and then filtered. The white crystalline solid was washed with 50% aqueous isopropanol (50 mL) and then dried at reduced pressure overnight to afford 29.1 grams of the title compound (88% yield).

Provenance & Evidence