Amination of pentafluoropyridine, 2,3,5,6 tetrafluoropyridine, 4 chlorotetrafluoropyridine, 3,5 dichlorotrifluoropyridine, octafluorotoluene, α,α,α,2,3,5,6 heptafluorotoluene, deca fluoro m xylene, decafluorobiphenyl, hexafluorobenzene, and pentafluorobenzene with liquid ammonia was investigated. Bis aminodefluorination temperatures for the majority of sub strates were shown to exceed significantly the corresponding temperatures of monoamino defluorination. The optimal conditions for selective preparation of mono and diamino polyfluoro(het)arenes were elucidated. An efficient method for isolation of particular polyfluorophenylenediamines from product mixtures formed in nonselective reactions of pentafluorobenzene and hexafluorobenzene with aqueous ammonia based on complexation with a crown ether is proposed. N. N. Vorozhtsov´s school made a considerable con tribution to the chemistry of polyfluoroaromatic com pounds: methods for the synthesis 1 and functionali zation 2,3a of base polyfluoroarenes were developed. Cur rently many polyfluoroarene derivatives are demanded for high tech processes and materials. In particular, diamino and dihydroxy(poly)fluoroarenes serve as struc tural blocks in the synthesis of polyimides used in fiber optic and thin film light guides, nanofilters, and mem branes, dielectric coatings, liquid crystalline displays, op tical diodes, laser media, etc. 4 Polyfluorinated amines of the benzene and pyridine series are used in the synthesis of biologically active compounds. 5It is known 6 that aminodehalogenation of arenes in aqueous ammonia, which is usually carried out in steel autoclaves at high temperatures (up to 250 °C), is often accompanied by competing transformations of arenes such as hydroxy and/or hydrodehalogenation involving water and the autoclave material. The version of the method of polyfluoroarene amination developed in this study im plies the use of liquid ammonia as both the reagent and the reaction medium. The possibility of aminodefluorina tion of some polyfluoroarenes with enhanced electrophi licity in liquid ammonia has been demonstrated previ ously. 7 The efficiency of liquid ammonia as a medium for aromatic nucleophilic substitution has been described in a review. 8 Note that the temperatures suitable for the work with liquid ammonia are limited by the range from -70 to 120 °C (m.p. -78 °C, critical point 133 °C). 9 It follows from analysis of published data that arene amino dehalogenation in liquid ammonia has a higher rate than that in aqueous ammonia; therefore, the processes are carried out at relatively low temperatures and the side reactions are minimized.The purpose of this study was to elucidate the condi tions for mono and diamination of polyfluorinated ben zene and pyridine derivatives in liquid ammonia, which are optimal as regards the selectivity and product yield, to develop simple and practically feasible techniques for separation of mixtures of amino compounds, and to syn thesize new high purity polyfluoroaromatic diamines de manded in high tech applic...

Rods (1D assemblies) formed by alternate crown ether and arylenediamine molecules are the motif of the supramolecular architecture of crystals of molecular associates of 18 crown 6 with tetrafluoro 1,4 and 1,3 phenylenediamines, hexafluoro 2,6 and 2,7 naphthylenedi amines. Molecules in the assemblies are arranged via H bond predominantly between the crown ether oxygen atoms and the polyfluoroarene amino group hydrogen atoms. Influence of the amino groups mutual arrangement and the aromatic framework size on the crystal su pramolecular architecture is characterized. Specific melting heats of the crystalline 1D assem blies of para and pseudo para arylenediamines are higher than those of meta and pseudo meta analogs; the associates having higher melting heats selectively crystallize from solutions of isomeric phenylene or naphthylenediamine mixtures.

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