Synthesis, Characterization, and Catalytic Hydrogenation Activity of New N-Acyl-Benzotriazole Rh(I) and Ru(III) Complexes in [bmim][BF4 ]

Abstract

The hydrogenation activity of new N-acyl-benzotriazole Rh(I) and Ru(III) complexes in ionic liquid media is reported in this study. Both complexes were completely soluble in 1-butyl-3-methylimidazolium tetrafluoroborate, [bmim][BF4 ], and they were able to catalyze the hydrogenation of styrene and 1-octene. While ethylbenzene conversion in styrene hydrogenation reached 84% when the Ru complex was used, 100% conversion was obtained with the Rh complex at 393 K in 6 h. Additionally, total conversion in 1-octene hydrogenation reached 100% with the Rh complex in [bmim][BF4 ] media. The hydrogenation of styrene and 1-octene in dimethyl sulfoxide (DMSO) and toluene was also studied to compare the solvent effect on catalytic system. The effect of some catalytic parameters such as temperature, H2 (g) pressure, and catalyst amount on the conversion was examined, and it was found that the conversion increased parallel to the increasing temperature and H2 pressure. The recyclability of catalysts was also investigated, and it was revealed that the Rh complex in particular maintained the activity for at least 10 cycles.