| Abstract
| - The reactions between strongly electron-rich aromatic substrates (1,3,5-tris(N,N-dialkylamino)benzenes,neutral carbon super nucleophiles) and diazonium salts produce moderately stable σ complexes (Whelandcomplexes). The reactivity of Wheland complexes with electrophiles (other diazonium salts, or 4,7-dinitrobenzofuroxan) produces exchange reactions in the electrophilic part: the better electrophile replacesthe less powerful electrophile. In the same way, in Wheland complexes with the 1,3,5-tris(morpholinyl)benzene, the 1,3,5-tris(piperidinyl)benzene replaces the less powerful nucleophile 1,3,5-tris(morpholinyl)benzene. Evidence is reported here indicating that for the title system the reaction of the attack of theelectrophilic reagent producing Wheland complexes is a reversible process. The final products of thediazo-coupling reactions undergo a further attack of some diazonium salts. From the final products ofthe double diazo-coupling reactions (diazo compounds), we collected evidence that is a clear instance ofcomplete reversibility of the diazo-coupling reaction.
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