A Convenient Modification of the Fischer Indole Synthesis with a Solid Acid
作者:Sosale Chandrasekhar、Somnath Mukherjee
DOI:10.1080/00397911.2014.984854
日期:2015.4.18
the cation exchange resin Amberlite IR 120 in refluxing ethanol. A variety of enolizable aldehydes, and ketones and several substituted phenylhydrazines could thus be converted to the corresponding indoles in excellent yields (70–88%). Reaction times were typically 6–10 h, with the resin being then filtered off and the product isolated after minimal workup. GRAPHICAL ABSTRACT
摘要 标题反应的新一锅版本包括在回流乙醇中加热羰基化合物、苯肼和阳离子交换树脂 Amberlite IR 120 的混合物。因此,各种可烯醇化的醛、酮和几种取代的苯肼可以以极好的收率(70-88%)转化为相应的吲哚。反应时间通常为 6-10 小时,然后将树脂过滤掉,并在最少的后处理后分离产物。图形概要
Synthesis of α-benzylated amides via electrocatalytic Favorskii rearrangement of 1, 3-diarylacetones
作者:Wei Liu、Wei Huang、Tianlei Lan、Haijuan Qin、Cheng Yang
DOI:10.1016/j.tet.2018.03.033
日期:2018.5
Electrolysis of 1,3-diarylacetones with aliphatic amines in Bu4NI/CH3CN to racemic Favorskii amides via benzyl group rearrangement has been developed. The electroconversion is easily conducted in a simple undivided cell under constant-current conditions at room temperature. The electrocatalytic Favorskiirearrangement of 1,3-diarylacetones including electron-withdrawing substituents was favored and
已开发了通过苄基重排将1,3-二芳基丙酮与Bu 4 NI / CH 3 CN中的脂肪族胺电解成外消旋的Favorskii酰胺。在室温下恒定电流条件下,在简单的不分格电池中可以轻松进行电转换。包括吸电子取代基的1,3-二芳基丙酮的电催化Favorskii重排是有利的,并且α-苄基酰胺具有良好的产率。当使用几种不对称酮作为底物时,观察到具有中等区域选择性的这种重排。该化学方法还提供了在酰胺的α-位上构建手性中心的有效方法。
The organocatalyzed domino Michael–aldol reaction revisited. Synthesis of enantioenriched 3-hydroxycyclohexanone derivatives by reaction of enals with α,α′-diaryl-substituted acetone
作者:James O. Guevara-Pulido、José M. Andrés、Rafael Pedrosa
DOI:10.1039/c5ra11215j
日期:——
The reaction of enals with α,α′-diaryl-substituted acetones (pKa > 18) catalyzed by (S)-1-(2-pyrrolidinylmethyl) pyrrolidine provides direct access to enantioenriched 2,5,6-trisubstituted-3-hydroxy cyclohexanones. The process constitutes a highly stereoselective organocatalytic tandem Michael-intramolecular aldolreaction. It has been demonstrated that the stereoselection is dependent on the reaction
(S)-1-(2-吡咯烷基甲基)吡咯烷催化的烯醛与α,α'-二芳基取代的丙酮(p K a > 18)的反应可直接进入对映体富集的2,5,6-三取代-3-羟基环己酮。该过程构成了高度立体选择性的有机催化串联迈克尔-分子间醇醛缩合反应。已经证明,立体选择取决于反应条件,因为仅顺式非对映异构体能够环化,并且抗非对映异构体参与反迈克尔过程,从而减少对映异构。
Synthesis of Acyclic Ketones by Catalytic, Bidirectional Homologation of Formaldehyde with Nonstabilized Diazoalkanes. Application of a Chiral Diazomethyl(pyrrolidine) in Total Syntheses of Erythroxylon Alkaloids
作者:Andrew J. Wommack、Jason S. Kingsbury
DOI:10.1021/jo401377a
日期:2013.11.1
This work offers a catalytic approach to convergent ketone assembly based upon formal and tandem C–H insertion of diazoalkanes in the presence of limiting amounts of monomeric formaldehyde, which is easily generated as a gas by thermolysis of the inexpensive and abundant paraformaldehyde (∼30 USD/kg). The method forms di-, tri-, and even tetrasubstituted acetones with high efficiency, and it has streamlined
Scaffold-Optimized Dendrimers for the Detection of the Triacetone Triperoxide Explosive Using Quartz Crystal Microbalances
作者:Daniel Lubczyk、Matthias Grill、Martin Baumgarten、Siegfried R. Waldvogel、Klaus Müllen
DOI:10.1002/cplu.201100080
日期:2012.2
and selectivity: The online detection of the explosivetriacetonetriperoxide (TATP) is an utmost challenge in security research. The great number of events wherein TATP was involved underlines the significance of solutions to trace that particular explosive material. New optimized functionalized polyphenylene dendrimers (see structure) have been synthesized that can be used as powerful affinity systems