Hydrochloric Acid → 7-Methoxy-3-(4-methoxyphenyl)thiochroman-4-one

Participants

Reaction Conditions

Reaction Steps

2-(4-Methoxyphenyl)-3-(3-methoxyphenylthio)propionic acid obtained in Example 24 was dissolved in benzene (20 ml) and thionyl chloride (4.1 ml, 55.9 mmol) was added thereto. The reaction mixture was heated for 2 hours at 80° C. When the reaction is completed, the reaction solution was concentrated under reduced pressure to remove benzene and cooled to 5° C. Benzene (10 ml) was added to the reaction solution and then tin(IV) chloride (4.1 ml, 34.9 mmol) was slowly added dropwise thereto. The reaction mixture was stirred for 12 hours and then water (30 ml), concentrated hydrochloric acid (10 ml) and chloroform (30 ml) were added thereto. The reaction solution was heated under refluxing for one hour and extracted with chloroform. The organic layer was washed with water and sodium hydrogen carbonate solution, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was purified with column chromatography (n-hexane:ethyl acetate=8:2) to obtain 1 g (yield in two reaction steps: 20%) of the title compound as a yellow solid.

Provenance & Evidence