Variety in the coordination modes of β-dicarbonyl compounds in metal complexes

Uranyl chelate complexes

The four-step, double-autocatalytic mechanism for transition-metal nanocluster nucleation, growth, and agglomeration described previously has been found to be more general; specifically, the four-step mechanism is shown to apply to the reduction of five transition metals that were examined—Pt, Ru, Ir, Rh, and Pd—under conditions where a high enough concentration of a strongly coordinating ligand is also present. Reaction temperature, metal concentration, solvent, and stirring rate do not change the reduction mechanism within experimental error and within the range of conditions studied herein. Changing the solvent from acetone to the higher dielectric constant solvent propylene carbonate does, however, change the product of metal reduction from solid bulk metal to soluble metal particles. Three alternative mechanisms (in addition to the 15 tested already) are ruled out, leaving the four-step double autocatalytic mechanism as the only mechanism to date that is able to fit the observed kinetic data. Additio...

The Four-Step, Double-Autocatalytic Mechanism for Transition-Metal Nanocluster Nucleation, Growth, and Then Agglomeration: Metal, Ligand, Concentration, Temperature, and Solvent Dependency Studies

Thermogravimetric studies of metal β-diketonates

Recent Development in arylgold chemistry

The chemistry of the solvated metal chelates. iii. the bis-(acetylacetonato)-uranium(vi) solvates1

ONE of the least-studied aspects of co-ordination chemistry is the thermal properties of metal complexes with organic chelating agents. With such easily available instruments as the automatic recording thermobalance and differential thermal analysis apparatus, physical parameters such as minimum and maximum temperature limits for dehydration and pyrolysis reactions, rate-studies of thermal decomposition reactions1, and detection of intermediate compounds formed during pyrolysis are easily attainable. Such information is needed in order to understand more fully the nature of certain types of thermal rearrangements and in synthesis work.

G. Robert Horton

Papers

The chemistry of the solvated metal chelates. iii. the bis-(acetylacetonato)-uranium(vi) solvates1

Differential thermal analysis of some transition metal ethylenediamine tetraacetic acid chelates.

The thermal properties of some amine tetraphenylboron salts