Citation
Frommer, Jane Elizabeth (1981) Syntheses and reactions of polymer-bound molybdenum complexes and hydrogenolyses of an alknyl cobalt carbonyl cluster. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/MD7N-W189. https://resolver.caltech.edu/CaltechETD:etd-08052009-075725
Abstract
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Co3(CO)9CCH2C(CH3)3 (1) was prepared and its hydrogen- mediated decomposition was studied. 1 reacted with hydrogen in aromatic solvents (60°C, 2-7 atm H2) to yield three products: 3,3-dimethylbutene (2), 2,2-dimethylbutane (3), and 4,4- dimethylpentanal (4). The final ratio of alkene to alkane to aldehyde was approximately 2.5 : 1.5 : 1.0. Kinetic data collected from both NMR- and vpc-monitored experiments indicated first order decomposition of starting material 1 and a hydrogen pressure dependence for the rate of appearance of total products. Nearly total inhibition of the hydrogenation was observed in the presence of carbon monoxide (CO:H2, 3.7:3.7 atm, 60°C). However, at elevated temperatures (85°), under the same CO/H2 atmosphere, aldehyde (4) production became the predominant reaction pathway at the expense of earlier-formed olefin 2. Incorporation of independently added olefins in the hydrogenation of 1 suggested the intermediacy of olefin in aldehyde and alkane production.
A polystyrene-attached n[superscript 5}-cyclopentadienyl(tricarbony1)-hydridomolybdenum complex (P-6) was prepared and its reactions with several THF-soluble bases were investigated. Enolates of β-dicarbonyl compounds quantitatively deprotonated P-6, giving polymer-bound salts of the corresponding anion ([...]-Cp(CO)3Mo[...], P-7). Equilibration studies involving polymers P-6 and P-7 and their soluble monomeric analogues in THF demonstrated that little change in pKa was induced by binding the molybdenum hydride to the polymer. Even though the polymer-supported partners in these experiments were not soluble and therefore rendered the reactions heterogeneous, the systems adhered reasonably well to conventional equilibrium behavior, as exhibited by a simple equilibrium analysis which yielded effectively constant Keq values. A polymer-bound carboxylic acid (P-1) and its conjugate base (P-2) also displayed essentially conventional equilibrium dynamics.
Item Type: | Thesis (Dissertation (Ph.D.)) |
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Degree Grantor: | California Institute of Technology |
Division: | Chemistry and Chemical Engineering |
Major Option: | Chemistry |
Thesis Availability: | Public (worldwide access) |
Research Advisor(s): |
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Thesis Committee: |
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Defense Date: | 22 August 1980 |
Record Number: | CaltechETD:etd-08052009-075725 |
Persistent URL: | https://resolver.caltech.edu/CaltechETD:etd-08052009-075725 |
DOI: | 10.7907/MD7N-W189 |
Default Usage Policy: | No commercial reproduction, distribution, display or performance rights in this work are provided. |
ID Code: | 3018 |
Collection: | CaltechTHESIS |
Deposited By: | Imported from ETD-db |
Deposited On: | 05 Aug 2009 |
Last Modified: | 21 Dec 2019 01:27 |
Thesis Files
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