Reactions of cyclic β-keto esters and other enol derivatives with 3-acetoxyamino-2-isopropylquinazolin-4(3H)-one: further oxidation of the cyclic α-(3,4-dihydro-2-isopropyl-4-oxoquinazolin-3-yl)amino ketones with lead tetraacetate leading to ring-expansion (in dichloromethane) and ring-cleavage (in methanol)
| العنوان: | Reactions of cyclic β-keto esters and other enol derivatives with 3-acetoxyamino-2-isopropylquinazolin-4(3H)-one: further oxidation of the cyclic α-(3,4-dihydro-2-isopropyl-4-oxoquinazolin-3-yl)amino ketones with lead tetraacetate leading to ring-expansion (in dichloromethane) and ring-cleavage (in methanol) |
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| المؤلفون: | Paul J. Edwards, Gordon A. Thomson, Robert S. Atkinson, Emma Barker |
| المصدر: | J. Chem. Soc., Perkin Trans. 1. :1533-1542 |
| بيانات النشر: | Royal Society of Chemistry (RSC), 1995. |
| سنة النشر: | 1995 |
| مصطلحات موضوعية: | Solvent, chemistry.chemical_compound, chemistry, Silylation, Organic chemistry, Methanol, Ring (chemistry), Cleavage (embryo), Medicinal chemistry, Enol, Isopropyl, Dichloromethane |
| الوصف: | The cyclic β-keto esters 12, 20, 22, 26, the β-diketone 28 and the enol silyl ethers 24 and 30 have been converted in 60–77% yields into the corresponding α-(oxoquinazolinyl)amino cyclic ketone derivatives 16, 21, 23, 29, 27, 25 and 31, respectively, by reaction with 3-acetoxyamino-2-isopropylquinazolin-4(3H)-one 11. Further oxidation of some of these products with lead tetraacetate gives products whose nature depends on the solvent used; in dichloromethane, 16, 21 and 25, which contain 5-membered ring ketones, give ring-expanded products 32, 38 and 39, respectively whereas, in methanol, ring-cleavage of 16, 25 and 27 occurs to give imino-esters 41, 44 and 42/43, respectively. Ring-expansion of 23, 27 and 31, which contain 6-membered ring ketones, does not occur and the only isolated product in each case is the benzoxazinone 40. A mechanism which accounts for this dependence on the solvent is presented: radical intermediates do not appear to be implicated. |
| تدمد: | 1364-5463 0300-922X |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::5bd78eb2a04fd337c5182e56e6dddc81 https://doi.org/10.1039/p19950001533 |
| رقم الأكسشن: | edsair.doi...........5bd78eb2a04fd337c5182e56e6dddc81 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 13645463 0300922X |
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