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.

Rhodium(I) complex of perfluorinated thiophene ligand was synthesized and heterogenized over the modified silica support. SEM, XRF, TGA and BET methods were used for the characterization of the heterogenized catalyst (SiAPTES-RhL). Heterogenization of catalyst and the catalytic activity tests were carried out in scCO₂ as a greener alternative to traditional reaction media. The catalytic activities of complex were investigated in hydrogenation reactions of some alkenes such as styrene, 1-octene and cyclohexene. 100% ethyl benzene conversion was observed at 370 K, 10 bar H₂ and 1900 psi total pressure in styrene hydrogenation. Also, it was found that the catalyst remains active at least throughout ten cycles. Similarly, the activity of the catalyst in the hydrogenation of 1-octene and cyclohexene was investigated. For 1-octene, 100% n-octan selectivity was obtained at 370 K and 10 Bar H₂. The catalyst was found to be effective at 370 K while the activity was low at 350 and 360 K in cyclohexen hydrogenation. When compared with the homogenous system, the heterogenized catalyst had more activity and selectivity and also reusability without losing its activity