9-Fluorenone is used in the preparation of antimalarial drugs. It is a fluorene derivative. Further, it is used in functional polymer and in dyes.
Li, S.; Zhang, Q. Mechanistic Studies on the Dibenzofuran Formation from Phenanthrene, Fluorene and 9-Fluorenone. Int. J. Mol. Sci. 2015, 16 (3), 5271-5284.
Fukui, Y.; Ohta, K.; Tominaga, K. Vibrational dynamics of the CO stretching of 9-fluorenone studied by visible-pump and infrared-probe spectroscopy. Faraday Discuss. 2015, 177, 65-75.