- Title
- Unexpected transformations of 3-(bromoacetyl)coumarin provides new evidence for the mechanism of thiol mediated dehalogenation of α-halocarbonyls
- Creator
- Magwenzi, Faith N, Khanye, Setshaba D, Veale, Clinton G L
- Date
- 2017
- Type
- text
- Type
- article
- Identifier
- http://hdl.handle.net/10962/66200
- Identifier
- vital:28916
- Identifier
- https://doi.org/10.1016/j.tetlet.2017.01.082
- Description
- publisher version
- Description
- The mechanism for the thiol mediated dehalogenation of α-halogenated carbonyls has remained an unresolved problem, despite its ongoing application in synthetic organic chemistry. Nakamura and co-workers first proposed that net dehalogenation occurs via sequential nucleophilic substitutions, while Israel and co-workers concluded that the rate at which dehalogenation occurred suggested that dehalogenation proceeds in a single concerted step. In this study, we investigated the debromination and nucleophilic substitution of 3-(bromoacetyl)coumarin with a variety of thiophenols, whose electron donating or withdrawing natures resulted in large variations in the degree of nucleophilic substitution and dehalogenation products, respectively. Results from these experiments, in addition to an unexpected formation of thioether containing dibenzo[b,d]pyran-6-ones from a Robinson annulation, has provided new evidence for this disputed mechanism.
- Format
- 5 pages, pdf
- Language
- English
- Relation
- Tetrahedron Letters, Magwenzi, Faith N., Khanye, Setshaba D., Veale, Clinton G.L. (2017) Unexpected transformations of 3-(bromoacetyl)coumarin provides new evidence for the mechanism of thiol mediated dehalogenation of α-halocarbonyls. Tetrahedron Letters. 58 (10), p.968 – 972. SN: 0040-4039. https://doi.org/10.1016/j.tetlet.2017.01.082, Tetrahedron Letters volume 58 number 10 968 972 March 2017 0040-4039
- Rights
- Elsevier B.V.
- Rights
- Use of this resource is governed by the terms and conditions of the Tetrahedron Letters Open Access Options Statement (https://www.elsevier.com/journals/tetrahedron-letters/0040-4039/open-access-options)
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Veale, Clinton G L (Dr)
Khanye, David Setshaba (Associate Prof)
RU Department of Chemistry
RU Department of Pharmacy
SDG 03. Good Health and Well-Being
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