Description
This thesis focuses on the synthesis and interactions of platinum and ruthenium metal complexes and their behavior as catalysts. The reaction of protic but weakly acidic substrates with the platinum complexes can be fine tuned by the presence of different phosphine ligands. Previous work showed that Pt[P(t-Bu₂R)]₂ (R = imidazol-2-yl) reacts reversibly with water. In order to prevent reversibility, the related 4,5 --diisopropylimidazol-2-yl system was synthesized. X-ray diffraction verifies hydrogen bond donation from each NH to the OH on the metal. A novel ruthenium catalyst which moves double bond over up to 30 positions, for substrates having carbon atom chain between C3 to C30 was developed. While isomerizing alkenols to aldehydes by an unknown pathway a catalytically inactive Ru-CO complex is formed. Other substrates do not form the Ru-CO complex. Several different approaches were tried to avoid the formation of Ru-CO complex, but little success was achieved in this respect. Symmetrical alkene-diols or their silyl ethers can be isomerized using the alkene isomerization catalyst to give ω-hydroxyaldehydes or the α-siloxy-ω-enol silyl ether products. Thus, symmetrical alkene-diols can be oxidized to have carbonyl group just at one end in one step, without going through the long route of selective protection of one OH group, followed by oxidation and then deprotection, which would be a three-step procedure. A new catalyst with phenyls rather than isopropyls on phosphorus isomerizes mixtures of alkenes from metathesis faster and also gives a mixture of E/Z isomers. The only difference between the two catalysts is that the E-selective catalyst 1 has a --Pi-Pr₂ moiety whereas the nonselective catalyst has a --PPh₂ unit.
