fluoren-9-ols by 4-nitro-1-chlorobenzotriazole in aqueous acetic acid is a second order reaction with a reaction constant of −1.4. The oxidation exhibits a kineticdeuteriumisotopeeffect indicating the cleavage of the 9-C*H bond in the rate-determiningstep. The title oxidation is compared with that by 1-chlorobenzotriazole.