Substitution mechanisms water exchange

Enormous acceleration of substitution at ruthenium(II) can be obtained by appropriate choice of ligands. Following the demonstration of remarkably rapid water exchange and complex formation (7d or D in mechanism) at the organometallic aqua-ion [Ru(ri5-C5Me5)(H20)3]2+ (150), comparably rapid substitution has been demonstrated at... 

It has been shown that the interpretation of catalytic reactions involving group VIII transition metals in terms of n complex adsorption possesses considerable advantages over classical theories by providing a link between theoretical parameters and chemical properties of aromatic reagents and catalysts. The concept has led to the formulation of a number of reaction mechanisms. In heavy water exchange the dissociative tt complex substitution mechanism appears to predominate it could also play a major role when deuterium gas is used as the second reagent. The dissociative mechanism resolves the main difficulties of the classical associative and dissociative theories, in particular the occurrence... 

Data for water exchange with Fe(H20)j+ are shown in Table 4.1. " The value for AV indicates an interchange dissociative mechanism, which is also reflected in data for the reaction of Fe + with tpy AV = -1-3.5 cm mol , ) and other ligands. " One of the earliest studies of substitution in a labile metal ion was of the reaetion of Fe + with bpy and phen in acid solution (Sec. 2.1.4). 

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