Rhodium dinuclear

The rhodium dithionite complex 1 is composed of the rhodium dinuclear moiety (RhCp )2((i-CH2)2 and the dithionite ion S2042-. The dithionite ion is very attractive as the external stimuli-responsive ligand because the ion has a weak covalent S—S bond (2.389 10 A), which is easily cleaved to form radical species by stimuli [9]. 

Scheme 5 Interconversions of a ruthenium-rhodium dinuclear species.

H. Nakai and K. Isobe, Crystalline-State Photochromism of Rhodium Dinuclear Complexes Having a Dithionite Group and Its Reaction Dynamics , Nippon Kessho Gakkaishi, 2008, 50, 348. 

Metal basicity and cooperative effects in the reactions of dinuclear pyrazolato rhodium complexes 98PAC779. 

Complex [(CXI )Ir(/j,-pz)(/i,-SBu )(/j,-Ph2PCH2PPh2)Ir(CO)] reacts with iodine to form 202 (X = I) as the typical iridium(II)-iridium(II) symmetrical species [90ICA(178)179]. The terminal iodide ligands can be readily displaced in reactions with silversalts. Thus, 202 (X = I), upon reaction with silver nitrate, produces 202 (X = ONO2). Complex [(OC)Ir(/i,-pz )(/z-SBu )(/i-Ph2PCH2PPh2)Ir(CO)] reacts with mercury dichloride to form 203, traditionally interpreted as the product of oxidative addition to one iridium atom and simultaneous Lewis acid-base interaction with the other. The rhodium /i-pyrazolato derivative is prepared in a similar way. Unexpectedly, the iridium /z-pyrazolato analog in similar conditions produces mercury(I) chloride and forms the dinuclear complex 204. 

Until recently, well-authenticated cases of the rhodium(II) oxidation state were rare, with the exception of the dinuclear carboxylates. They fall into two main classes, although there are other rhodium(II) complexes ... 

The dinuclear rhodium(II) acetate is described in section 2.8.2 the dinuclear structure is retained on one-electron oxidation, but when ozone is used as the oxidant, a compound with a trinuclear Rh30 core is formed, analogous to those formed by Fe, Cr, Mn and Ru. (It can also be made directly from RhCl3.)... 

Although there is a severe paucity of vibrational data for the molecular form of O2 chemisorbed on rhodium surfaces, it is possible to visualize the dinuclear and trinuclear complexes as models for the associative chemisorption of O2 on rhodium. The pq-o values of the complexes Rh2(02)i,2 show little... 

Several dinuclear rhodium complexes such as the above-mentioned [Rh2(OAc)4] have been used as hydrogenation catalysts [22, 23]. Maitlis and coworkers have studied the chemistry and catalytic activity of the [Rh(C5Me5)Cl2]2 complex and related complexes. Kinetic studies suggested that cleavage into monomer occurs in the most active catalysts [90]. 

Dinuclear rhodium(II) carboxylate complexes with cage-like structures 46, in which carboxylate groups bridge the two metals and a... 

In the case of BDPP with a bite angle of 90°, the high-pressure NMR and high-pressure IR studies showed the structures of the hydrido dicarbonyl diphosphine resting state as an axial-equatorial BPT. Similar behavior was observed for the furanoside diphosphines. Dinuclear rhodium species in equilibrium with the mononuclear pentacoordinate rhodium hydride carbonyl diphosphines have been found for these ligands. The position of this equilibrium depends on the hydrogen concentration and the ligands. The rate... 

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