Reduction of nitrobenzene catalyzed by immobilized copper catalyst under carbon monoxide and water
Titel:
Reduction of nitrobenzene catalyzed by immobilized copper catalyst under carbon monoxide and water
Auteur:
Yanez, Jorge E. Rivas, Angel B. Alvarez, Juan Ortega, Marisol C. Pardey, Alvaro J. Longo, Clementina Feazell, Rodney P.
Verschenen in:
Journal of coordination chemistry
Paginering:
Jaargang 59 (2006) nr. 15 pagina's 1719-1728
Jaar:
2006-10-15
Inhoud:
Catalytic activity for reduction of nitrobenzene to aniline (98%) and azobenzene (2%) using a poly(4-vinylpyridine)-immobilized Cu catalyst [Cu(II)/P(4-VP)] under a CO atmosphere in aqueous 2-ethoxyethanol was studied as a function of the various reaction parameters ([Cu], P(CO), T, and nitrobenzene/Cu molar ratio). Reaction rates were first-order in [Cu]tot over 1.0-12.0 wt.% range and in P(CO) over the 6.8-27.2 atm range. The catalytic activity proved to be non-linear in nitrobenzene/Cu ratio over 41-500 molar ratio range. These results suggest that the rate-limiting step is preceded by reversible coordination of nitrobenzene to a carbonyl-Cu(I) immobilized species. A catalytic mechanism consistent with the data is proposed.