Title:
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Hydroformylation of Functionalised Olefins
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Electronic and steric effects induced by various phosphine ligands on the
regioselective rhodium-catalysed hydroformylation of butyl acrylate and enamides
were investigated in this thesis. The first chapter describes the hydroformylation
reactions reported in the literature, followed by chapter two, which presents the
synthesis of modified dppb and phosphite ligands based on a biphenol and binol
backbone. Ligand design represents a straightforward way to control the outcome of
f the reaction, such as the catalytic regioselectivity and activity. The influence of
modified dppb and phosphite ligands as well as some other parameters on the
hydroformylation reaction was investigated; this forms the content of the third
chapter contained within this thesis. As a result of the work featured here, we
deduced that because electron deficient phosphine and phosphite ligands showed an
increase in the rate of the reaction for butyl acrylate, leading to a higher activity of
the rhodium catalyst, it appears that the CO dissociation is the rate-determining step;
this is in line with the literature. The maximum rate and branched selectivity (95%)
was obtained with dppbCF3 (TOF = 4743 hoI). This result was further extended to
enamides in Chapter 4, where a similar observation on the reactivity was observed
when using phosphite ligands bearing electron-withdrawing substituents. One of the
most significant results is seen in the application of phosphite ligands for rhodiumcatalysed
hydroformylation of enamines, which is to our knowledge, have not been
previously employed for this type of the reaction. High-branched selectivity (up
99%) and high rate were observed in the hydroformylation ofvinylphthalimide in the
presence of bulky phosphites, where the reaction was complete in less than 1 h.
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