Phenol → 2-Hydroxy-9H-thioxanthen-9-one

Participants

Reaction Steps

150 ml concentrated sulfuric acid was added to 16 g (0.103 mol) thiosalicylic acid. 60 g (0.44 mol) phenol was added portion wise. The temperature rose to 50° C. during the addition. The mixture was allowed to cool down to room temperature and stirred for 30 minutes at room temperature. The mixture was heated to 80° C. for 48 hours. The mixture was allowed to cool down to room temperature and carefully added over one hour to 3 l water at 75° C. The mixture was stirred for an additional hour at 60° C. and allowed to cool down to room temperature. 2-hydroxy-9H-thioxanthen-9-one was isolated by filtration and dried. 12.9 g of 2-hydroxy-9H-thioxanthen-9-one (55%) was isolated. 2-hydroxy-9H-thioxanthen-9-one was sufficiently pure to be used without further purification.

Provenance & Evidence