Thermodynamic Studies of Metal Carboxylates

In an effort to better understand the chemistry and physical properties of metal clusters a quantitative study of the chemical reactivity of numerous metal carboxylates was performed. Dimeric metal carboxylates were chosen for such a study because of the extensive structural information available on them. The thermodynamics of adduct formation for 1:1 and 2:1 adducts formed by Lewis bases with rhodium(II) butyrate were studied in benzene and methylene chloride solutions. Electrochemical studies of these adducts were carried out in methylene chloride solutions. The thermodynamic data clearly demonstrates substantial changes in the acidic and redox properties of the second metal as a result of base coordination to the first. The metal-metal bonding in the system causes this dimer to be a most unusual Lewis acid, as evidenced by deviations of the E and C predicted enthalpies from those observed. The unusual Lewis acid properties are attributed to the enhanced (pi)-backbonding capability of the rhodium(II) center as a result of extensive mixing of orbitals with (pi)-symmetry on the two metal centers. This causes the rhodium(II) center to be very effective in (pi)-backbonding to the ligands. The reduction potentials of Rh(,2)(C(,4)H(,7)O(,2))(,4)('+), Rh(,2)(C(,4)H(,7)O(,2))(,4)B('+), and Rh(,2)(C(,4)H(,7)O(,2))(,4)B(,2)('+) are analyzed, and provide further support for the extensive (pi)-backbonding capabilities of this metal cluster.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Chemistry

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Long, John Reid

• Chemistry, Inorganic

Language dc:language

eng

Identifier

(UMI)AAI8108588

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/67245