Amination fluoro-carbonyl compounds

Fluoroalkyl- and fluoroarylamines. Imines formed (with Dowex-50 Reform resin as catalyst) with fluoro carbonyl compounds undergo prototropic shift on treatment with EtjN. Hydrolysis of the benzylidene isomers gives the fluorinated amines. 

A recent adaptation of the procedure employing perchlorate and fluoro-borate salts has been reported by Leonard and Paukstelis (J5). This report includes proof of structure by direct comparison to iminium salts prepared by protonation of enamines. The general reaction reported was that of a ketone or aldehyde with a secondary amine perchlorate to give iminium salts. A large structural variety of carbonyl compounds and several amine... 

Ring closure by reaction between an amino and a fluoro function is a frequently used method (see Chapter 9) it is sometimes convenient to use a heterocyclic carbonyl group as a precursor of the amine, and thus reduce the number of compounds that have to be isolated and purified in a multistep synthesis. Pyrimidinediones are susceptible to this type of conversion as is demonstrated in the synthesis of a diaza-acridinone. 

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