Degree Type

Dissertation

Date of Award

1985

Degree Name

Doctor of Philosophy

Department

Chemistry

Abstract

The thiocarbyne cations, Cp(,2)Fe(,2)(CO)(,2)((mu)-CO)((mu)-CSR)('+) (R = Me, Bz, All), react with a variety of nucleophiles (Nuc = H('-), MeS('-), PHS('-), BzS('-), PhSe('-) and BzMgCl) to give bridging carbene complexes, Cp(,2)Fe(,2)(CO)(,2)((mu)-CO) (mu)-C(SR)Nuc . The cis-syn isomers of (mu)-hydridothiocarbene complexes, Cp(,2)Fe(,2)(CO)(,2)((mu)-CO) (mu)-C(H)SMe and Cp(,2)Fe(,2)(CO)(,2)((mu)-CO) (mu)-C(H)SCH(,2)Ph , have been isolated. In CDCl(,3), these complexes undergo a slow cis-syn to cis-anti interconversion and an even slower cis-syn/trans-syn isomerization. Solutions (in benzene, CHCl(,3), CH(,2)Cl(,2), acetone, and CH(,3)CN) of (mu)-dithiocarbene complexes, Cp(,2)Fe(,2)(CO)(,2)((mu)-CO) (mu)-C(SMe)SR , are equilibrium mixtures of all possible cis and trans isomers. The initially formed (mu)-selenothiocarbene complex, Cp(,2)Fe(,2)(CO)(,2)((mu)-CO) (mu)-C(SMe)SePh , converts to a (mu)-carbyne complex, Cp(,2)Fe(,2)(SePh)(CO)((mu)-CO)((mu)-CSMe), at 0(DEGREES)C. In contrast, the (mu)-dithiocarbene complex, Cp(,2)Fe(,2)(CO)(,2)((mu)-CO) (mu)-C(SMe)SPh , converts to Cp(,2)Fe(,2)(SPh)(CO)((mu)-CO)((mu)-CSMe) at 40(DEGREES)C;Reaction of Cp(,2)Fe(,2)(CO)(,2)((mu)-CO)((mu)-CSMe)('+) with primary and secondary amines gives presumably the unstable complexes, CP(,2)Fe(,2)(SMe)(CO)((mu)-CO)((mu)-CNR(,2)). Tertiary amines do not react;A one electron reduction of Cp(,2)Fe(,2)(CO)(,2)((mu)-CO)((mu)-CSMe)('+) gives the deep emerald green radical, Cp(,2)Fe(,2)(CO)(,2)((mu)-CO)((mu)-CSMe)(.), which has been characterized by IR, EPR and UV-visible spectroscopy. Ligand exchange reactions of Cp(,2)Fe(,2)(CO)(,2)((mu)-CO)((mu)-CSMe)('+) are catalyzed by the radical, and apparently proceed through a mechanism involving dissociative loss of CO from Cp(,2)Fe(,2)(CO)(,2)((mu)-CO)((mu)-CSMe)(.);Reaction of Na Co(CO)(,4) with Cp(,2)Fe(,2)(CO)(,2)((mu)-CO)((mu)-CSMe)('+) under UV photolysis gives Cp(,2)Fe(,2)Co(CO)(,3)((mu)-CO)(,2)((mu)(,3)-CSMe). An x-ray diffraction study of this cluster shows that it has an L-shaped triangular structure, but there is no Co-Fe bond on one edge of the triangle. The CSMe group bonds through the carbyne carbon to all three metals, and in addition the sulfur coordinates to the cobalt atom.

DOI

https://doi.org/10.31274/rtd-180813-6098

Publisher

Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/

Copyright Owner

Norman Clark Schroeder

Language

en

Proquest ID

AAI8514436

File Format

application/pdf

File Size

304 pages

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