I
<sub>2</sub>
‐Promoted [3+2] Cyclization of 1,3‐Diketones with Potassium Thiocyanate: a Route to Thiazol‐2(3
<i>H</i>
)‐One Derivatives
作者:Zhenyu An、Yafeng Liu、Pengbo Zhao、Rulong Yan
DOI:10.1002/adsc.202100228
日期:2021.7
An I2-promoted strategy has been developed for the synthesis of thiazol-2(3H)-onederivatives from 1,3-diketones with potassium thiocyanate. This [3+2] cyclization reaction involves C−S and C−N bond formation and exhibits good functional group tolerance. A series of thiazol-2(3H)-onederivatives are obtained in moderate to good yields.
已开发出一种 I 2促进策略,用于从 1,3-二酮与硫氰酸钾合成 thiazol-2(3 H )-one 衍生物。这种 [3+2] 环化反应涉及 C-S 和 CN 键的形成,并表现出良好的官能团耐受性。以中等至良好的产率获得了一系列 thiazol-2(3 H )-one 衍生物。
Annulation of CF<sub>3</sub>–Imidoyl Sulfoxonium Ylides with 1,3-Dicarbonyl Compounds: Access to 1,2,3-Trisubstituted 5-Trifluoromethylpyrroles
A lithium-bromide-promoted nucleophilicsubstitution/annulation cascade reaction between CF3-imidoyl sulfoxonium ylides and 1,3-dicarbonyl compounds has been established, and the corresponding 1,2,3-trisubstituted 5-trifluoromethylpyrroles have been obtained in 27–78% yield. This reaction features a broad substrate scope and generates dimethylsulfoxide and H2O as byproducts.
已经建立了溴化锂促进的 CF 3 -亚氨酰基锍叶立德与 1,3-二羰基化合物之间的亲核取代/环化级联反应,并在 27-78 年获得了相应的 1,2,3-三取代 5-三氟甲基吡咯% 屈服。该反应具有广泛的底物范围,并生成二甲基亚砜和 H 2 O 作为副产物。
Ion Pair First and Second Acidities of Some β-Diketones and Aggregation of Their Lithium and Cesium Enediolates in THF
作者:Antonio Facchetti、Andrew Streitwieser
DOI:10.1021/jo0491915
日期:2004.11.1
the metal enolates to dimers. Similarly, ion pair pK values could be determined for some of these metal enolates going to the corresponding dimetal dienediolates which were also found to form dimers. These equilibria are more complicated to analyze because aggregation affects both sides of the proton transfer equilibria. The results show that all of the species measured exist mostly as dimers at concentrations
Photocatalytic synthesis of tetra-substituted furans promoted by carbon dioxide
作者:Ya-Ming Tian、Huaiju Wang、Ritu、Burkhard König
DOI:10.1039/d1sc06403g
日期:——
compounds in carbon dioxide (CO2) atmosphere under mild conditions. It was found that CO2 could be incorporated at the diketone enolic OH position, which was key to enabling the cleavage of a C–O bond during the rearrangement of a cyclopropaneintermediate. This method allows for the same-pot construction of two isomers of the high-value tetra-substituted furan scaffold. The synthetic scope and preliminary
Evaluation of TCS/ZnCl<sub>2</sub> with Acetic Anhydride as an Acetylating Reagent for Methylene Ketones
作者:Tamer K. Khatab、Saad S. Elmorsy、Doria S. Badawy
DOI:10.1080/104265090507920
日期:2005.1.1
Abstract A new route for the preparation of β -diketones which have applications in organic synthesis by the reaction of methylene ketones, acetic anhydride, TCS and ZnCl 2 in the solvent methylenechloride at room temperature produces the corresponding β -diketones in excellent yield.