Potassium Carbonate → 2,6-dimethylthieno[2,3-b][1,5]benzoxazepin-4(5H)-one

Participants

Reaction Conditions

Reaction Steps

To a solution of N-(2-hydroxy-6-methylphenyl)-2-bromo-5-methyl-3-thiophenecarboxamide (3.0 g) in dimethyl sulfoxide (25 ml) was added potassium carbonate (2.5 g), and the mixture was stirred at 145° C. for 2 hours. The reaction system was cooled to room temperature and poured into ice water. The precipitated crystals were collected by filtration and the filtrate was extracted with chloroform, washed twice with water, and dried over sodium sulfate. The solvent was evaporated under reduced pressure and the residue and the crystals obtained earlier were purified by silica gel column chromatography (chloroform:methanol=20:0-20:1). The obtained solid was collected by filtration from diisopropyl ether-hexane to give 2,6-dimethylthieno[2,3-b][1,5]benzoxazepin-4(5H)-one (700 mg).

Provenance & Evidence