Cornforth reagent → 4-Benzoyl-5-hydroxybenzocyclobutene-1-carboxylic acid

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Reaction Steps

3.0 g of 4-(α-hydroxybenzyl)-5-hydroxybenzocyclobutene-1-carboxylic acid are dissolved in 30 ml of dichloromethane and over a period of 10 minutes, while stirring, 30 g of pyridinium dichromate in 100 ml of dichloromethane are added dropwise thereto. Stirring is then carried out for 7 hours at room temperature, and the mixture is decanted off from the black residue, filtered over silica gel, concentrated to dryness by evaporation and crystallised from ether/hexane. 4-benzoyl-5-hydroxybenzocyclobutene-1-carboxylic acid is obtained having a melting point of 167°-169°.

Provenance & Evidence