The solvent-free selective epoxidation of dec-1-ene has been achieved under mild conditions and using atmospheric oxygen as the sole oxidant. Furthermore this has been conducted in the absence of radical initiators which is a first for such an oxidation to the best of our knowledge. The selective epoxidation of alkenes typically requires the use of supported active metals such as gold or silver. These have been studied for the epoxidation of dec-1-ene however they were found to be inactive in the absence of radical initiators. Alternatively, this transformation has been achieved using a graphitic oxide catalyst which harbours no active metal species. This is yet another remarkable example of the potential of carbocatalysis for green chemistry. The commonly raised issues when using carbocatalysts such as identification of active species and presence of impurities are addressed. A range of graphitic oxides have been produced using modified Hofmann and Hummers methods with attention given to the effect of amount of oxidant used compared to commonly employed literature standards. We conclude that the popular highly oxidised Hummers materials used in the bulk production of graphene may not be the optimum material for all applications and that specification of graphitic oxides may be required to suit each application. An investigation of activity in the epoxidation of dec-1-ene partnered with a full characterisation of the surface suggests that an optimum level of oxidation is required along with the need for a surface free of potential poisons such as sulphur. We also evaluate the current methods used in the preparation and separation of these materials and suggest that for applications such as epoxidation alternative techniques may be required in order to realise its potential as a carbocatalyst. This work provides the basis for the development of an efficient catalyst for the selective epoxidation of α-alkenes, eradicating the need for expensive stoichiometric reagents or toxic radical initiators.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:667921 |
| Date | January 2015 |
| Creators | Pattisson, Samuel David |
| Publisher | Cardiff University |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://orca.cf.ac.uk/78390/ |
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