Meisenheimer-Wheland complexes between 1,3,5-tris(N,N-dialkylamino)benzenes and 4,6-dinitrotetrazolo[1,5-a]pyridine. Evidence of reversible C-C coupling in the S(E)Ar/S(N)Ar reaction.
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 coupling products which are "double sigma-complexes" (W-M), Wheland-like on the 1,3,5-tris(N,N-dialkylamino)benzene moiety and Meisenheimer-like on the 4,6-dinitrotetrazolopyridine moiety. These complexes were moderately stable at low temperature, and they were characterized by NMR spectroscopy methods. (1)H NMR experiments at variable temperature strongly indicate that the formation of these complexes by a nucleophile/electrophile attack is a reversible process.
Boga
Carla
C
Department of Organic Chemistry A. Mangini, Alma Mater Studiorum - University of Bologna, Viale del Risorgimento, 4 - 40136 Bologna, Italy. boga@ms.fci.unibo.it
Del Vecchio
Erminia
E
Forlani
Luciano
L
Mazzanti
Andrea
A
Lario
Cira Menchen
CM
Todesco
Paolo E
PE
Tozzi
Silvia
S