Synthesis of Bridged Bicyclic Ethers and Fused Oxetanes from Pyran-4-ones via Tandem Solvent Trapping and Norrish Type II Cyclization1
| العنوان: | Synthesis of Bridged Bicyclic Ethers and Fused Oxetanes from Pyran-4-ones via Tandem Solvent Trapping and Norrish Type II Cyclization1 |
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| المؤلفون: | Scott S. Mitchell, Rehan Basta, Frederick G. West, P. V. Fisher, Mike Fleming |
| المصدر: | The Journal of Organic Chemistry. 64:1626-1629 |
| بيانات النشر: | American Chemical Society (ACS), 1999. |
| سنة النشر: | 1999 |
| مصطلحات موضوعية: | Solvent, chemistry.chemical_compound, Ethanol, chemistry, Tandem, Bicyclic molecule, Pyran, Organic Chemistry, Polymer chemistry, Trapping, Methanol, Irradiation |
| الوصف: | Polyalkyl pyran-4-ones 1a-c were irradiated in methanol or ethanol. Although the expected solvent trapping products 3 could be observed, extended irradiation times allowed exclusive formation of secondary photoproducts 4 and 5 in combined yields of 37-64%. These bicyclic compounds are believed to arise from gamma-hydrogen abstraction by the excited enone chromophore of 3, followed by closure of the resulting biradical through one of two possible pathways. Moderate stereoselectivity was observed in the radical coupling to produce 4, whereas the analogous closure to 5 was completely diastereoselective. Tautomerization of the enol precursors to 5 also occurred with complete selectivity for protonation from the exo face. Overall, this process converts simple, planar heterocycles and alkanols into complex products in a single transformation. |
| تدمد: | 1520-6904 0022-3263 |
| DOI: | 10.1021/jo9821224 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b5e82afc555064b136f45709bf62f03e https://doi.org/10.1021/jo9821224 |
| رقم الانضمام: | edsair.doi.dedup.....b5e82afc555064b136f45709bf62f03e |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 15206904 00223263 |
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| DOI: | 10.1021/jo9821224 |