Substitution ligand rearrangement

On carbonylation in methylene chloride it undergoes the substitution of the diene ligands, rearrangement, and cis-trans isomerization to yield 64 (97JOM(530) 259). l,r-(l,2-Ethylene)-3,3 -imidazol-2,2 -diylidene and the dimer [(T -cod)Rh (ir-Cl)] form the dinuclear species 65. 

Os3(CO)i2, nine products were obtained. Three of these were identified as the substituted adducts Os3(CO)12(Ph3P)i2- Gc = 1, 2, or 3), but for others, the fission of C-H and C-P bonds had occurred to yield a variety of compounds in which there were radical variations in the structure and mode of bonding of the triphenylphosphine group. Figure 29 shows details of the structures of six of these complexes. As indicated above, significant ligand rearrangements have taken place. 

The formation of Mo02+ complexes and their substitution, ligand exchange and rearrangement (fluxionality) reactions have been reviewed.195... 

There are attempts to use other iron nitrosyls, both monomeric complexes and clusters [85-90]. Photochemical liberation of NO follows three main reaction pathways (1) photooxidation-substitution, (2) photoreduction, and (3) ligand rearrangement or decomposition as a result of photoreaction. 

Ligand Rearrangement and Substitution Reactions of Transition Metal Complexes... 

Some reversible polyhedral rearrangements have been described. Although most are of academic curiosity, others provide insight into the substitution mechanisms and methods by which ligand rearrangements might occur. This is clearly evident in certain examples and merely proposed (based on surrounding evidence) in others. 

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