Cyclopentadienyl ruthenium sulfide carbonyls and thiophene activation by iron and rhodium
Ogilvy, Ann Elizabeth
This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.
Permalink
https://hdl.handle.net/2142/21604
Description
Title
Cyclopentadienyl ruthenium sulfide carbonyls and thiophene activation by iron and rhodium
Author(s)
Ogilvy, Ann Elizabeth
Issue Date
1990
Doctoral Committee Chair(s)
Rauchfuss, Thomas B.
Department of Study
Chemistry
Discipline
Chemistry
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Chemistry, Inorganic
Language
eng
Abstract
The desulfurization and reduction of the sulfur-containing organic compounds in petroleum products is the objective of catalytic hydrodesulfurization (HDS), one of the largest applications of transition-metal catalysis. However, the specific mechanism for the process is not well understood. This thesis addresses certain aspects of HDS research from an organometallic perspective.
A proposed intermediate during thiophene decomposition features thiophene $\sigma$-bound through an $\alpha$-carbon to a surface metal atom. Results from the reaction of ($\rm C\sb5H\sb5$)Fe(CO)(PPh$\sb3$)(2-C$\sb4$H$\sb3$S) and methyl triflate indicate the possible formation of two S-methylated configurational isomers. The first non-mercury containing bimetallic $\mu$-thienyl compound, ((C$\sb5$H$\sb5$)Fe(CO)$\sb2$) $\sb2$(2,5-C$\sb4$H$\sb2$S) was structurally characterized.
The reaction of thiophenic compounds with Fe$\sb3$(CO)$\sb{12}$ resulted in metal insertion into the C-S bond. The known benzothiaferrole $\rm Fe\sb2(C\sb8H\sb6S)(CO)\sb6$ (1) was hydrogenated to give an insoluble iron-containing solid and a series of ethylbenzene derivatives. Oxidizing agents convert 1 to the carbonylated heterocycle thiocoumarin. $\rm Fe\sb2$(2-MeC$\sb4$H$\sb3$S)(CO)$\sb6$ desulfurizes to give the corresponding ferrole complex when heated.
"$\rm \lbrack (C\sb5 Me\sb5)Rh(TMT)\rbrack\sp{2+}$ (TMT = tetramethylthiophene) reacts with cobaltocene to give the new compound ($\rm C\sb5Me\sb5)Rh(\eta\sp4$-TMT), 2. The $\eta\sp4$-TMT ligand in 2 desulfurizes upon reaction with Fe$\sb3$(CO)$\sb{12}$ to give ($\rm C\sb5Me\sb5)Rh(C\sb4Me\sb4)Fe(CO)\sb3$. An x-ray diffraction study confirms that the Fe(CO)$\sb3$ fragment is included in the $\rm C\sb4Me\sb4$ ring. The thermolysis of 2 resulted in the formation of an ionic compound. The structurally characterized cation consists of four ($\rm C\sb5Me\sb5)Rh(\eta\sp4$-TMT) ""units"" bound to a central rhodium atom in a square planar fashion creating a ""pinwheel"" structure. A new mechanism for thiophene HDS was proposed."
(($\rm C\sb5Me\sb4Et)Ru$) $\sb2$S$\sb6$(CO)$\sb2$ eliminates SCO to give (($\rm C\sb5Me\sb4Et)Ru$) $\sb2$S$\sb5$(CO). (($\rm C\sb5Me\sb4Et)Ru$) $\sb2$S$\sb4$ reacts with CO to form (($\rm C\sb5Me\sb4Et)Ru$) $\sb2$S$\sb4$(CO) (3). This is the first example of a metal-centered ligand addition to a cyclopentadienyl metal sulfide. The x-ray structure of 3 shows a $\rm Ru\sb2S\sb4$ core in a chair conformation with the bridging ($\eta\sp1$-S$\sb2$) ligands in a trans configuration. In the presence of phosphines, (($\rm C\sb5Me\sb4Et)Ru$) $\sb2$S$\sb4$ reacts with CO to form (($\rm C\sb5Me\sb4Et)Ru$) $\sb2$S$\sb2$(CO)$\sb2$.
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.