Diphenic acid → 9-Oxofluorene-4-carboxylic acid

Participants

Reaction Steps

Diphenic acid (500 g, 2.06 Mol) was reacted with concentrated sulfuric acid (1250 mL, S.G. 1.84) at 140° C. for 35 minutes following the procedure of Huntress et al.1The red solution was cooled and precipitated by pouring the mixture into 15 L of distilled water. The yellow precipitate was boiled with 10 L of water, filtered and boiled with a further 10 L of water. The dried yellow product 9-fluorenone-4-carboxylic acid (463 g, 81% yield) was used in the next step without further purification.

Provenance & Evidence