Summary: | This thesis investigates the potential catalysis of the ring-opening polymerisation (ROP) of propylene oxide (PO). Numerous industrial and academic research groups have investigated the mechanism and developed more efficient catalysis, the leading catalysts at the moment being Double-Metal Cyanides (DMC). This thesis has considered variations to DMC catalysts as well as other potential catalysts. A combination of metal cyanides and amines were also used to form complexes, which were then characterised and tested for polymerisation. The process of ring-opening one unit of PO was examined using organic dithiocarbamates. A range of amines was used to synthesise dithiocarbamates, which were found to ring-open PO along with other epoxides. The scope was extended to include metal bis(dithiocarbamates) and consider any catalytic properties they may have towards polymerisation. Organic dithiocarbamates ranging from small groups such as methyl to rings like piperidine were attached via (bromomethyl)benzene units to form arenes with multifunctional arms. The number of bromomethyl units on the benzene varied from two to six, which allowed the arrangement of the arms to be studied and form iniferters for living polymerisation reactions. The dithiocarbamate chemistry was extended to include other transition metals, namely ruthenium and palladium. This work was developed using bidenetate phosphine ligands as well as allyl groups acting as capping end groups. Various substituted piperazine dithiocarbamates were reacted to potentially act as linking units to form multimetallic arrays.
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