Graphite oxide (GO), a carbon material prepared in one step from low cost commercial materials, and graphene oxide have been found to catalyze a wide range of reactions including oxidations, hydrations, and dehydrations, as well as cationic or oxidative polymerizations. Applicable in both small molecule and polymer chemistry, this single, metal-free catalyst shows remarkable breadth, including the combination of the aforementioned reactions in an auto-tandem fashion to form advanced substrates, such as chalcones, from simple starting materials. Some of these reactions, such as the selective oxidation of alcohols to aldehydes, have been shown to be dependent on the presence of molecular oxygen, suggesting that this may be the terminal oxidant. Aside from its eminently valuable reactivity, the use of GO as a catalyst also presents practical advantages, such as its heterogeneous nature, which facilitates separation of the catalyst from the desired product.
The use of this simple material in synthetic chemistry, as well as others like it, is distinct from other forms of catalysis in that the active species is carbon-based, heterogeneous and metal-free (as confirmed by ICP-MS and other spectroscopic techniques). This has led us to propose the term “carbocatalyst” to describe such materials. With dwindling supplies of precious metals used in many common organic reactions, the use of inexpensive and widely available carbocatalysts in their place will ensure that commercial processes of fundamental importance can continue unabated. Moreover, as we have shown with just one material, carbons are capable of facilitating a broad range of reactions. / text
Identifer | oai:union.ndltd.org:UTEXAS/oai:repositories.lib.utexas.edu:2152/ETD-UT-2012-05-4977 |
Date | 27 June 2012 |
Creators | Dreyer, Daniel Robert |
Source Sets | University of Texas |
Language | English |
Detected Language | English |
Type | thesis |
Format | application/pdf |
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