Ruthenium incorporation into molecules and materials: New catalysts and strategies to prepare stable ruthenium-capped olefins
Date of Award
Doctor of Philosophy (PhD)
Michael B. Sponsler
Triflates, Ruthenium, Olefins
Chemistry | Physical Sciences and Mathematics
Strategies such as olefin metathesis were investigated to make stable mixed-valence compounds and materials incorporating metal atoms in polyolefin chains, which are potential precursors in molecular electronics.
New olefin metathesis catalysts, having the general molecular formula (H 2 IMes)Ru(=CHR)(Cl) 2 (3-bromopyridine) 2 and (H 2 IMes)Ru(=CHR)(Cl) 2 (PCy 3 ), where R = Me, Et, and Pr, were prepared. Their kinetic reactivity towards olefins was studied. The PCy 3 catalysts initiated faster (6-14 times) than the Grubbs catalyst where R = Ph. The 3-bromopyridine catalysts were similar in reactivity to the Grubbs catalyst, where R = Ph.
Polyacetylene was prepared in powder and film forms from acetylene using ruthenium olefin metathesis. A new material, metathesis-doped polyacetylene (MDPA), with ruthenium incorporation in the polyacetylene, which was soluble in common organic solvents, was prepared. The 3-bromopyridine catalyst where R = Ph effected the polymerization of 1-hexyne and propargyl alcohol.
Two new ring-constrained polyenes, 1,5-dimethylene-1,2,3,4,5,6,7,8-octahydronapthalene and 1,5-dimethylene-decahydronapthalene, and two polyynes, 1,4-pentadiyne and 3,3,6,6-tetramethyl-1,4,7-octatriyne, were investigated as precursors for ring-constrained diruthenium complexes through sequential ene-yne, ring-closing, and stoichiometric olefin metathesis reactions. All compounds failed to give the desired complexes under a variety of conditions.
A new class of ruthenium alkylidene complexes of trimethylphosphine (H 2 IMes)Ru(=CHR)(Cl) 2 (PMe 3 ), where R = Ph and Et, were prepared. They were metathesis-unreactive at room temperature. Thus, a method of stopping the metathesis reactivity was found by the simple addition of PMe 3 . A new ruthenium alkylidene, namely (PCy 3 )Ru(=CHC 6 H 5 )(Cl) 2 (3-bromopyridine) 2 , was prepared. A new set of Fischer carbenes was prepared, including a tris(trimethylphosphine) complex with molecular formula (PMe 3 ) 3 Ru(=CHOCH 2 CH 3 )(Cl) 2 .
Two dienyl ditriflates, 2,3,4,6,7,8-hexahydronapthalene-1,5-ditriflate and 3,4,4a,7,8,8a-hexahydronapthalene-1,5-ditriflate, were prepared, the former in higher yield and greater reproducibility than done before. Their reactivity and potential application as ring-constrained precursors to prepare diruthenium complexes were investigated.
Surface provides description only. Full text is available to ProQuest subscribers. Ask your Librarian for assistance.
Williams, Joseph Ephraim, "Ruthenium incorporation into molecules and materials: New catalysts and strategies to prepare stable ruthenium-capped olefins" (2005). Chemistry - Dissertations. Paper 50.