One-Pot Construction of Medium- and Large-Sized Ring Substituted Furans. Efficient Conversion to Dibenzofurans, Coumestans, and 4-Pyrones
作者:Yong Rok Lee、Jung Yup Suk、Byung So Kim
DOI:10.1021/ol0056933
日期:2000.5.1
New efficient synthesis of medium- and large-sizedring substituted furans is achieved by 1,3-dicarbonyl compounds with vinyl sulfides in the presence of Ag(2)CO(3)/Celite (Fétizon's reagent) in a one-pot procedure. The synthesized furans can be further converted to biologically interesting compounds such as dibenzofurans, coumestans, benzofuroquinolinone, and 4-pyrone.
Clay Catalysis: A Simple and Efficient Synthesis of Enolthioethers from Cyclic Ketones
作者:Bouchta Labiad、Didier Villemin
DOI:10.1055/s-1989-27180
日期:——
Montmorillonite KSF in refluxing toluene catalyses the synthesis of 1-alkyl- and 1-arylthioalkenes from ketones and thiols (thiophenol or 1-butanethiol).
Efficient Synthesis of Dihydrofurans with Sulfide Groups by Ceric(IV) Ammonium Nitrate-Mediated Oxidative Cycloaddition of 1,3-Dicarbonyl Compounds to Vinyl Sulfides. Application to the Synthesis of Benzo[<i>b</i>]naphtho[2,3-<i>d</i>]furan-6,11-dione and First Total Synthesis of Millettocalyxins C and Pongamol Methyl Ether
作者:Yong Rok Lee、Keon Yong Kang、Gun Joon Lee、Won Kyong Lee
DOI:10.1055/s-2003-41023
日期:——
Ceric(IV) ammonium nitrate-mediated oxidative cycloaddition of 1,3-dicarbonyls to vinylsulfides afforded substituted dihydrofurans with sulfide groups in moderate yields. This new synthetic method has been applied to thesynthesis of benzo[b]naphtho[2,3-d]furan-6,11-dione and furanoflavone natural products such as millettocalyxins C and pongol methyl ether.
Mono- and Bisadducts from the Addition of Thianthrene Cation Radical Salts to Cycloalkenes and Alkenes
作者:Ding-Quan Qian、Henry J. Shine、Ilse Y. Guzman-Jimenez、John H. Thurston、Kenton H. Whitmire
DOI:10.1021/jo0104633
日期:2002.6.1
Thianthrene cationradicalsalts, Th(*)(+) X(-)(X(-) = a, ClO(4)(-); b, PF(6)(-); c, SbF(6)(-)), add to cycloalkenes (C(5)-C(8)) in acetonitrile (MeCN) to form 1,2-bis(5-thianthreniumyl)cycloalkane salts and 1,2-(5,10-thianthreniumdiyl)cycloalkane salts, most of which have now been isolated and characterized. These are called bis- (3, 6, 9, 12) and monoadducts (4, 7, 10, 13). The proportional amount