[5C + 1N] Annulation: a novel synthetic strategy for functionalized 2,3-dihydro-4-pyridones
作者:Dewen Dong、Xihe Bi、Qun Liu、Fangdi Cong
DOI:10.1039/b505569e
日期:——
A novel and facile route to functionalized mono/bicyclic 2,3-dihydro-4-pyridones has been developed via formal [5C + 1N] annulation of readily available alpha-alkenoyl ketene-(S,S)-acetals with various aliphatic primary amines.
A new and efficient approach to 2-hydroxybenzophenone derivatives via [5C + 1C] annulation of α-alkenoyl-α-aroyl ketene dithioacetals and nitroalkanes
作者:Xiao-bo Zhao、Yi-meng Wang、Hai-feng Yu、Yuan-cheng Lv、Si-ao Jiang、Nan Wang
DOI:10.1016/j.tet.2021.132427
日期:2021.9
efficient protocol for the synthesis of 2-hydroxybenzophenone derivativesthrough [5C+1C] annulation of α-alkenoyl-α-aroyl ketene dithioacetals and nitroalkanes had been developed. In the presence of 1 equivalent of K2CO3 in DMF at 70 °C, a range of α-alkenoyl-α-aroyl ketene dithioacetals smoothly react with nitroalkanes to provide various 2-hydroxy benzophenone derivatives in excellent yields. The protocol
开发了一种通过 α-烯酰基-α-芳酰基烯酮二硫缩醛和硝基烷烃的 [5C+1C] 环化合成 2-羟基二苯甲酮衍生物的新的有效方案。在70°C 下,在 DMF 中存在 1 当量 K 2 CO 3时,一系列 α-烯酰基-α-芳酰基乙烯酮二硫缩醛与硝基烷烃顺利反应,以优异的产率提供各种 2-羟基二苯甲酮衍生物。该方案反应条件温和,无副产物生成,收率高,不存在化学选择性和区域选择性并存的问题,底物范围广。
[5C + 1S] Annulation: A Facile and Efficient Synthetic Route toward Functionalized 2,3-Dihydrothiopyran-4-ones
作者:Xihe Bi、Dewen Dong、Yan Li、Qun Liu、Qian Zhang
DOI:10.1021/jo052032g
日期:2005.12.1
A facile and efficient synthetic route toward highly substituted 2,3-dihydrothiopyran-4-ones 2 has been developed via a formal [5C + 1S] annulation of readily available alpha-alkenoyl ketene-(S,S)-acetals 1 with sodium sulfide nonahydrated salt (Na(2)S(.)9H(2)O) and utilized in the synthesis of 2-(4-chlorophenyl)-6-(morpholin-4-yl)-4H-thiopyran-4-one 51, an inhibitor of DNA-dependent protein kinase (DNA-PK).
Regio- and stereoselective synthesis of 2-cyclopentenones via a hydrogenolysis-terminated Heck cyclization of β-alkylthio dienones
作者:Bangyu Liu、Gang Zheng、Xiaocui Liu、Cong Xu、Jingxin Liu、Mang Wang
DOI:10.1039/c3cc37571d
日期:——
Palladium-catalyzed cyclization of β-alkylthio dienone derivatives affords 2-cyclopentenones in a regio- and stereoselective manner in the presence of silane. CâS activation, intramolecular carbopalladation and hydrogenolysis construct the cascade process.