9-fluorenone diaryl ketone

Diaryl ketones, such as o-bromobenzophenone and fluorenone carboxylic acids," are reduced by HI and red phosphorus in acetic acid or propionic acid under reflux, giving o-bromophenylphenyl-methane and fluorene carboxylic acid in high yields. 

In 2013, Chen et al. developed a direct and economical lluorination of benzyUc C-H bond (Scheme 3.27) [78]. Using diaryl ketones as photosensilizers, visible-light-induced fluorination of various benzylic C-H bonds was accomplished with Selectfluor as fluorine source. Selective mono- and difluoiination can be controlled with different photosensitizers. 9-Fluorenone catalyzes the monofluori-nation, while xanthone favors benzylic C-H difluoiination. Also, in the same year, light-induced pyridination of benzylic C-H bond was developed [79]. 

Traditionally cyanohydrins have been prepared by processes that require the establishment of an equilibrium between a ketone and its corresponding cyanohydrin. For many ketones, especially those that are sterically hindered, the position of the equilibrium is unsatisfactory for the effective synthesis of the cyanohydrin. We describe herein a general method for the synthesis of cyanohydrins which does not depend on an equilibrium process. As a result this synthetic procedure can be used to convert a wide variety of dialkyl, diaryl, and arylalkyl ketones into their corresponding cyanohydrins. In addition to the described conversion of benzophenone into its cyanohydrin, acetophenone, fluorenone, tert-butyl phenyl ketone, and a wide variety of aliphatic ketones have been converted into cyanohydrins by this general procedure (Table... 

Fluorenone oxime was recovered unchanged after being heated with PPA at 120°, but at 180° it was rearranged in almost quantitative yield (Conley )- Conley found PPA to be a superior solvent-catalyst for the Schmidt rearrangement. He added sodium azide in portions to a mixture of a diaryl, aryl-alkyl, symmetrical or unsymmetrical ketones with 15-20 parts of PPA at a temperature in the range 25-75° until evolution of nitrogen ceased, and obtained amides in yields mainly of 80-90%. Doorenbos and Wu studied the conversion of cholestanone and... 

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