Date of Award
5-2003
Degree Type
Thesis
Degree Name
Doctor of Philosophy (PhD)
Department
Chemistry
Supervisor
Professor M.J. McGlinchey
Abstract
This dissertation focuses on the synthesis, characterization and reactivity of several types of arene manganese systems.
The reaction of potassium tert-butoxide with [(ɳ6-trindane)Mn(CO)3][BF4], 58c, was investigated in attempts to funtionalize 58c at the benzylic positions. It was demonstrated that complex 58c undergoes three C-H insertions and a haptotropic shift when treated with potassium tert-butoxide. As well, other trindane complexes including [(ɳ6-trindane)Mn(CO){O(OMe)3}2][BF4], 98, and [(ɳ6-trindane)Re(CO)3][PF6], 99, have been synthesized in hopes of alkylating the exo benzylic positions and develop an organometallic route to sumanene, a key fragment of C60 that has not yet been synthesized. The former compound, 98, was characterized by X-ray crystallography.
In order to probe the generality of the novel reaction exhibited by the trindane system, other [(arene)Mn(CO)3]+ systems were studied in which the arene is bicyclic or tricyclic and possesses attached 5-, 6- or 7-membered rings. In particular, the syntheses of [(ɳ6-indane)Mn(CO)3][BF4], 84, [(ɳ6-tetralin)Mn(CO)3][PF6], 103, and [(ɳ6-dibenzosuberane)Mn(CO)3][BF4], 102, and their reactions with potassium tert-butoxide in the presence of donor ligands are presented. The products of these reactions were characterized by infrared and 1H, 13C and 31P NMR spectroscopy and mass spectrometry.
The molecular dynamics of two hexaethylbenzene (HEB) complexes, [(ɳ6-HEB)Mn(CO)3][BF4], 147, and (ɳ6-HEB)Mn(CO)2Br, 148, were examined using low-temperature NMR spectroscopy. The activation barrier (ΔG≠) for ethyl rotation for 147 was determined to be ~ 11.5 kcal mol-1. Crystallographic data was obtained for 148, which demonstrated the 1,3,5-distal-2,4,6-proximal geometry, a feature common to transition metal HEB complexes.
Finally, extended Hückel molecular orbital (EHMO) calculations were carried out for four polycyclic frameworks ligated to organometallic fragments: anti-dibenzpentalene, 157, and syn-dibenzpentalene, 158; fluoradenyl, 159, and fluoranthene, 160. Each of these systems exhibited unique dynamic behaviour, which are interpreted using a molecular orbital rationale.
Recommended Citation
Reginato, Nada, "Polycyclic Compounds of Manganese" (2003). Open Access Dissertations and Theses. Paper 790.
http://digitalcommons.mcmaster.ca/opendissertations/790