Understanding anionic Chugaev elimination in pericyclic tetracene formation
The reaction pathway for the formation of tetracenes from the diols 1,2-C6H4(CHOHC≡CAr)2 , LiHDMS, CS2 and MeI has been modelled by computational methods at the CBS-QB3 level of theory. Comparison of PhCHOC(=S)YCCPh (Y = S- or SMe) indicates a slight kinetic advantage for the anionic system towards...
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| Format: | Article |
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Elsevier
2016
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| Online Access: | https://eprints.nottingham.ac.uk/31578/ |
| _version_ | 1848794230606004224 |
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| author | Burroughs, Laurence Ritchie, John Woodward, Simon |
| author_facet | Burroughs, Laurence Ritchie, John Woodward, Simon |
| author_sort | Burroughs, Laurence |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | The reaction pathway for the formation of tetracenes from the diols 1,2-C6H4(CHOHC≡CAr)2 , LiHDMS, CS2 and MeI has been modelled by computational methods at the CBS-QB3 level of theory. Comparison of PhCHOC(=S)YCCPh (Y = S- or SMe) indicates a slight kinetic advantage for the anionic system towards [3,3]-sigmatropic rearrangement [Eact(calc.) 19.7 vs 21.8 kcal mol-1]. Using anthracene-based models, 10-{SC(=O)Y}-4a,10-dihydroanthracene (Y = S- or SMe), allows direct comparison of both syn and anti-manifolds in the neutral vs. anionic Chugaev elimination. Syn elimination of [HSC(=O)S]- is distinctly favoured [Eact(calc.) 11.4 kcal mol-1] vs. syn elimination of neutral methylated HSC(=O)SMe [Eact(calc.) 27.5 kcal mol-1]. The smaller barrier to syn elimination of the anionic leaving group is in accord with the low temperature conditions required for this Chugaev reaction (60 oC) and suggests a general advantage in carrying out Chugaev eliminations in anionic manifolds. |
| first_indexed | 2025-11-14T19:12:53Z |
| format | Article |
| id | nottingham-31578 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| last_indexed | 2025-11-14T19:12:53Z |
| publishDate | 2016 |
| publisher | Elsevier |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-315782020-05-04T17:39:19Z https://eprints.nottingham.ac.uk/31578/ Understanding anionic Chugaev elimination in pericyclic tetracene formation Burroughs, Laurence Ritchie, John Woodward, Simon The reaction pathway for the formation of tetracenes from the diols 1,2-C6H4(CHOHC≡CAr)2 , LiHDMS, CS2 and MeI has been modelled by computational methods at the CBS-QB3 level of theory. Comparison of PhCHOC(=S)YCCPh (Y = S- or SMe) indicates a slight kinetic advantage for the anionic system towards [3,3]-sigmatropic rearrangement [Eact(calc.) 19.7 vs 21.8 kcal mol-1]. Using anthracene-based models, 10-{SC(=O)Y}-4a,10-dihydroanthracene (Y = S- or SMe), allows direct comparison of both syn and anti-manifolds in the neutral vs. anionic Chugaev elimination. Syn elimination of [HSC(=O)S]- is distinctly favoured [Eact(calc.) 11.4 kcal mol-1] vs. syn elimination of neutral methylated HSC(=O)SMe [Eact(calc.) 27.5 kcal mol-1]. The smaller barrier to syn elimination of the anionic leaving group is in accord with the low temperature conditions required for this Chugaev reaction (60 oC) and suggests a general advantage in carrying out Chugaev eliminations in anionic manifolds. Elsevier 2016-03-31 Article PeerReviewed Burroughs, Laurence, Ritchie, John and Woodward, Simon (2016) Understanding anionic Chugaev elimination in pericyclic tetracene formation. Tetrahedron, 72 (13). pp. 1686-1689. ISSN 0040-4020 http://www.sciencedirect.com/science/article/pii/S0040402016300886 doi:10.1016/j.tet.2016.02.025 doi:10.1016/j.tet.2016.02.025 |
| spellingShingle | Burroughs, Laurence Ritchie, John Woodward, Simon Understanding anionic Chugaev elimination in pericyclic tetracene formation |
| title | Understanding anionic Chugaev elimination in pericyclic tetracene formation |
| title_full | Understanding anionic Chugaev elimination in pericyclic tetracene formation |
| title_fullStr | Understanding anionic Chugaev elimination in pericyclic tetracene formation |
| title_full_unstemmed | Understanding anionic Chugaev elimination in pericyclic tetracene formation |
| title_short | Understanding anionic Chugaev elimination in pericyclic tetracene formation |
| title_sort | understanding anionic chugaev elimination in pericyclic tetracene formation |
| url | https://eprints.nottingham.ac.uk/31578/ https://eprints.nottingham.ac.uk/31578/ https://eprints.nottingham.ac.uk/31578/ |