Sol-gel entrapped lipophilic and hydrophilic ruthenium-, rhodium-, and iridium-phosphine complexes as recyclable isomerization catalysts

O,N‐Bidentate Ruthenium Azo Complexes as Catalysts for Olefin Isomerization Reactions

“…Allylbenzene is used as a model substrate for the isomerization applying all kinds of catalysts, such as the transition metals Ti, Zr, [28] Co, [29] Rh, [30,31] Ir, [32] Au, [33] and Ru, [34][35][36][37] or Mg, [38] or even a non-metal compound like P. [39] While 1-octene is also extensively used as a model substrate, [58] these two compounds are selected as representatives alkenes to evaluate the performance of the complexes [(η 6 -pcymene)RuCl(L n )] (n = 1-7). To investigate the catalytic activity, all ligands and precursor complexes have been screened under identical reaction conditions and no isomerization activity could be observed.…”

Synthesis, characterization, reactivity and theoretical studies of ruthenium carbonyl complexes containing ortho-substituted triphenyl phosphanes

“…Ruthenium compounds with phosphane ligands are known to have applications in various fields of catalysis, including hydrogenation [7][8][9], isomerization [10][11][12][13][14] and hydroformylation reactions [15][16][17][18]. Although ruthenium-phosphanes are well-known systems, they are still of interest.…”

The Co‐Entrapment of a Homogeneous Catalyst and an Ionic Liquid by a Sol–gel Method: Recyclable Ionogel Hydrogenation Catalysts

“…Blum and Avnir [1] have pioneered the entrapment of molecular catalysts within silica by the sol-gel method. Catalytic materials can be prepared to promote a wide variety of reactions including isomerization, [2] disproportionation, [3] hydrogenation and dehalogenation, [4] hydroformylation, [5] Pauson-Khand coupling, [6] epoxidation, [7] and Heck coupling. [8] Catalysts entrapped in silica have been found to show resistance to poisoning, as a result incompatible reactions can be conducted in tandem.…”

“…Measurable leaching was detected from 4, Rh on carbon and Rh on alumina, in each case the heaviest leach was detected after the first run, this value is reported in Table 3. In Figure 5 leaching is expressed as a percentage of the rhodium present and therefore the concentration of rhodium in the product is 30-50 times less for [Rh 2 4 entrapped in an ionogel than 5 % Rh on alumina or carbon. The magnitude of leaching is not great enough to explain the loss of activity observed for the commercial catalysts and the most active metal sites must be being lost.…”

“…The magnitude of leaching is not great enough to explain the loss of activity observed for the commercial catalysts and the most active metal sites must be being lost. Leaching from 4 has little effect on the activity and may originate from Rh contamination, owing to [Rh 2 …”