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A Raney nickel-hydrazine hydrate method for reducing aromatic nitro groups has been extended to fluorene derivatives including those having >0=0, >C=C<, NHCOCF3 and other functional groups, and dinitro compounds. For the less soluble substances, certain specific directions must be followed, but most yields were 90% or higher and the first crop out of the reaction mixture was of good quality. A nitro compound with an azomethine linkage gave a product with both functions reduced. Some new substances are described.The convenient steam bath reduction, in excellent yields, of some aromatic nitro compounds to amines with Raney nickel and hydrazine hydrate in ethanol was reported by Balcom and Furst.2 3Since then, a few reports8•4 have appeared in which this method has been tried on one or two nitro compounds with good results, after failure or poor results with other methods. This work is presented because there have been several recent reports of reduction of nitrated derivatives of fluorene in poor yield or by methods more tedious than this, because we have found this reaction, with few exceptions, thoroughly satisfactory, and because in certain of the procedures, notably with dinitro compounds and fluorenone derivatives, simple but necessary precautions must be observed.It was found,5 and confirmed,2 that without a catalyst nitro compounds did not undergo reduction at room temperature. Some can be reduced to the amine in refluxing alcohol by hydrazine hydrate alone5•6 but yields are often low and the reaction is slow. Higher temperatures often lead to side reactions. Recently, reduction with palladized charcoal and hydrazine hydrate was reported.7 Yields,

Thirty-two new azomethine derivatives of fluorene have been prepared. Several catalysts not used previously for the preparation of azomethines are reported.

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