Influence of the reaction conditions on the reduction of nitrobenzene catalyzed by poly(4-vinylpyridine) anchored [Rh(COD)(2-PIC)(2)](PF6) complex.

Reported here are the influence of the reaction conditions variation (carbo n monoxide pressure, P(CO), rhodium content, [Rh], and temperature) on the catalytic reduction of nitrobenzene to aniline by [Rh (COD) (2-pic)(2)] (PF 6) (COD = 1,5-cyclooctadiene, 2-pic = 2-picoline) immobilized on poly(4-vin ylpyridine) in contact with 80 % aqueous 2-ethoxyethanol under water-gas sh ift reactions conditions (RDGA, CO + H2O <----> CO2 + H-2). The turnover fr equencies for the production of aniline displayed a first order dependence on the pressure of CO in the 0 - 1.9 atm range, a nonlinear dependence on r hodium content on the 0.9 - 12.2 wt. % range indicating that the active spe cies have different nuclearities. The temperature dependence followed a seg mented Arrhenius plot in the 70 - 130 degreesC ranges. These data are discu ssed in terms of a possible mechanism.