Meisenheimer-Wheland Complexes between 1,3,5-Tris(N,N-dialkylamino)benzenes and 4,6-Dinitrotetrazolo1,5-apyridine.Evidence of Reversible C-C Coupling in the SEAr/SNAr Reactiont

摘要

Reactions between a superelectrophilic carbon reagent, 4,6-dinitrotetrazolopyridine, and 1,3,5-tris(N,N-dialkylamino)benzenes, a supernucleophilic carbon reagent series, afford C-C couplingproducts which are°double σ-complexes± (W-M), Wheland-like on the 1,3,5-tris(N,N-dialkylami-no)benzene moiety and Meisenheimer-like on the 4,6-dinitrotetrazolopyridine moiety. These com-plexes were moderately stable at low temperature, and they were characterized by NMRspectroscopy methods. ~1H NMR experiments at variable temperature strongly indicate that theformation of these complexes by a nucleophile/electrophile attack is a reversible process.