Addition of Hydrogen and Hydrogen Cyanide to Carbon–Carbon Double and Triple Bonds

Rhodium and Iridium β-Diiminate Complexes – Olefin Hydrogenation Step by Step

“…[30] Most hydrogenation cycles involving Rh or Ir alternate between 16-e and 18-e species. [28,31] Even in cases where several active species are involved, they all go through intermediates with the same electron count. In our case, the catalysis appears to involve a 14-e/16-e mechanism, at least for the more hindered olefins, which may be attributed to steric factors.…”

8.17 Homogeneous Catalytic Hydrogenation of CåC and CåC

“…[Ru(η 6 -C 10 H 14 )(η 2 -triphos)Cl]PF 6 Benzenes a 128 RuH 2 (H 2 ) 2 (PCy 3 ) 2 Benzenes, polyaromatics 129 [Ru 3 (η 6 -C 6 Me 6 ) 2 (η 6 -C 6 H 6 )(μ 3 4 Benzenes a 130 RuCl 2 (PTA)(η 6 -C 10 H 14 ); RuCl(PTA) 2 (η 6 -C 10 H 14 )…”

“…193,194 Another system that also provides for good catalysts, although at a slower rate, is based on the thiosemicarbazonates 14. 190 Table 2 Catalyst systems for the reduction of alkynes to alkenes 3 4 169,175,176 SO 3 ]} is one of the few homogeneous systems that affords transalkenes from the hydrogenation of alkynes. 195 This selectivity has been attributed to the involvement of a dimeric ruthenium complex.…”

“…1,2 The most commonly used catalyst system for the reduction of a wide variety of nonconjugated alkenes is Wilkinson's catalyst {chlorotris(triphenylphosphine)rhodium(I), [RhCl(PPh 3 ) 3 ]} and extensive reviews have been published. [2][3][4] The hydrogenation conditions are mild. The presence of small amounts of impurities, such as oxygen or peroxides, can increase the reaction rate, 5,6 larger amounts of impurities cause the formation of rhodium metal.…”

Separation of gas mixtures by supported complexes

“…(7,8) The pentacyanocobaltate(II) anion attains a d 6 octahedral configuration via a net H 2 addition to two cobalt centers as shown. (2) However, there is a slow degradation (or aging) in aqueous systems since water also adds to the cobalt center to give both hydroxyl and hydride products. These complexes might be stabilized by miscellular incorporation or by the use of biphasic systems.…”