Aromatic substitution internal

The effect of the substitution of a heavy-atom directly onto the nucleus of aromatic compounds (internal heavy-atom effect) on intercombinational radiative and nonradiative processes can be seen by examination of experimental data obtained for naphthalene and its derivatives. The data obtained by Ermolaev and Svitashev<104) and analyzed by Birks(24) to obtain individual rate constants for the various processes are collected in Table 5.9. 

Bochkarev et al. 16 prepared hyperbranched dendrimers via polymerization of tris(pentafluorophenyl)germanium anions resulting in branched macromolecules with Ge-branching centers. Building block propagation was attributed to metal anion, aromatic substitution of a phenyl, para-fluoro-moiety. Thus, treatment of Ge-monomer 8 with excess Ge-anion afforded hyperbranched macromolecules with an internal framework resembling tetrakisGedendrimer 9 (Scheme 8.4). Subsequently, Sn and Si were employed for hyperbranched dendrimer construction. 

SN2Ar SNAr SNi See SNAr. Nucleophilic aromatic substitution, also called SN2Ar. Substitution nucleophilic internal. 

A different approach was employed by Pinhey et al to test the presence of aryl radical species in aromatic substitution by aryllead triacetates. An excellent system bearing an internal trap for free... 

The only known example of the catalytic nucleophilic aromatic substitution involves the use of Rh(III) complexes (e.g., 40). The first demonstration was made in 1980 [99]. The metal center is so electrophilic that an internal alcohol nucleophile substitutes directly without an added base. 

Prof V. Charushin is author of over 380 publications in the fields of heterocyclic and medicinal chemistry, including the hoo Nucleophilic Aromatic Substitution of Hydrogen, (Academic Press, New York, 1994), several chapters in Advances in Heterocyclic Chemistry and Progress in NMR Spectroscopy, over 20 review articles, and a lot of papers in international journals. He is a member of the editorial boards for Mendeleev Communications, Russian Chemical Reviews, Russian Chemical Bulletin, and Russian Journal of Organic Chemistry. 

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