A short series of diazo compounds containing a primary alcohol and one or more
other carbene traps were synthesised. The result in each case, from rhodium
(11) acetate mediated decomposition where products could be isolated was that
O-H insertion is observed at the expense of all other intramolecular processes.
A few other catalysts were tried and a similar result was observed. Even
catalysts such as copper (11) acetate, commonly used for cyclopropanations did
not lead to any cyclopropanes, O-H insertion being the only observed product.
The variation of the rate of decomposition of a small selection of diazo
compounds with a range of rhodium (11) catalysts is described. The catalysts
chosen represent a wide range of ligand pKa, (0.17 -t 12.40, trifluorobutyrate
and acetamide respectively). The results show that the rate of decomposition of
the diazo substrates is at a maximum when the pKa of the ligand is .. 10. The
relative rates of decomposition of the diazo compounds are unaffected by the
The synthesis of a-alkoxyesters by rhodium mediated decomposition of
a-diazoesters was considered. Use of ethyl 2-diazo-3-phenylpropanoates leads
to the formation of O-H insertion products and ethyl cinnamates. The ratio of
insertion product to cinnamate was found to vary with the ligand on rhodium .
. The use of chiral a-diazophenylacetates was unsuccessful in inducing any
chirality to the newly formed chiral centre. The use of chiral rhodium catalysts
was also tried but again found to be unsuccessful. The possible reasons for this
have been discussed.
A Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University.