2-Benzoylbenzoic Acid → 3-Phenyl-3-(5-bromo-1-benzotriazolyl)phthalide

Participants

Reaction Steps

10.0 g (0.04 mol.) of commercial 2-benzoylbenzoic acid and 7.8 g (0.04 mol.) of 5-bromobenzotriazole were added to 300 ml of dried xylene, and refluxed for 8 hours as heat was applied thereto by means of the dehydration-reflexing apparatus. After cooling, the insoluble material was filtered off with suction, and the filtrate was concentrated to obtain 12.4 g of oily substance. This oily substance was separated and purified by flash column chromatography (silica gel: 400 g, eluate: hexane-ethyl acetate (3:2 by volume) mixture) to obtain the intended compound, 3-phenyl-3-(5-bromo-1-benzotriazolyl)phthalide (22), in the form of white crystals. Yield 8.1 g, Melting Point 128° to 131° C.

Provenance & Evidence