Phloroglucinol → 1,3-dihydroxy-9H-thioxanthen-9-one

Participants

Reaction Conditions

Reaction Steps

A mixture of phosphorous pentoxide (3.71 g, 26.15 mmol) and methane sulfonic acid (27.05 mL, 0.42 mmol) was stirred at 90° C. for about one hour until a clear solution was obtained. To the reaction solution were added thiosalicylic acid (1.04 g, 6.76 mmol) and phloroglucinol (1.02 g, 8.11 mmol), followed by stirring at 70° C. for 10 minutes. After the reaction was completed, the reaction mixture was poured in 1 L of ice water. The resulting precipitate was allowed to stand at 4° C. overnight, combined, washed with water, and then dried under reduced pressure to give an orange solid compound. This compound was separated and purified by silica gel column chromatography (developing solvent: ethyl acetate:n-hexane=1:1 (v/v)) to give a yellow solid compound (1.14 g, 51.1%).

Provenance & Evidence