Reactivity ligand exchange

The most important feature of metal alkoxides is their facile ligand exchange reactivity originating from predominantly electrostatic nature of the M—O bonding. This leads to quick achievement of coordination equilibria. When alkoxides - derivatives of one alcohol - are dissolved in a different alcohol, they transform instantaneously into, most often, more thermodynamically stable mixed ligand species in solutions. The latter often possesses increased solubility in organic solvents ... 

Trends in reactivity for ligand-exchange reactions of octahedral metal carbonyls. G. R. Dobson, Acc. Chem. Res., 1976, 9, 300-306 (48). 

Water solubility across the group is low however, hydrolysis of the reactive ligands and/or ligand exchange in the environment or tissues of organisms could lead to the formation of species that are more soluble, casting doubt on the relevance of some of the modelled data. 

Ligand Exchange Reactions and Core-induced Reactivity.. . 110... 

In transfer hydrogenation with 2-propanol, the chloride ion in a Wilkinson-type catalyst (18) is rapidly replaced by an alkoxide (Scheme 20.9). / -Elimination then yields the reactive 16-electron metal monohydride species (20). The ketone substrate (10) substitutes one of the ligands and coordinates to the catalytic center to give complex 21 upon which an insertion into the metal hydride bond takes place. The formed metal alkoxide (22) can undergo a ligand exchange with the hydride donor present in the reaction mixture, liberating the product (15). 

Chemisorption Adsorbate Orientation Competitive Chemisorption Adsorbate Exchange Adsorbate Reactivity Electrocatalvsis Synthesis Mode of Coordination Ligand Substitution Ligand Exchange Ligand Reactivity Homoqeneous Catalysis... 

Chanda, M., O Driscoll, K. F., Rempel, G. L., Ligand exchange sorption of arsenate and arsenite anions by chelating resins in ferric ion form I. Weak-base chieating resin Dow XFS-4195. Reactive Polym. 7,1988, 251-261. 

The principal photochemical reactions of metal complexes include dissociation, ligand exchange and redox processes. Unlike organic photoreactions (which take place almost exclusively from the S3 or T3 states), the excited state formed on irradiation depends on the wavelength employed. Hence the quantum yield often depends on the wavelength of the irradiating source. The excited-state processes give rise to a reactive intermediate which may find application in the synthesis of new compounds. 

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