描述了一种有效的规程,用于使用Cu(OAc)2催化剂和黄原酸酯作为硫源,通过α-C–H官能化,从易于获得的2-碘对二苯并呋喃中合成2-酰基苯并[ b ]噻吩。反应性较低的2-溴查耳酮也以良好的产率产生相应的2-酰基苯并噻吩。该反应通过硫的原位结合进行,然后进行铜催化的环化反应,生成没有外部酰基源的2-酰基苯并噻吩。合成的重要性通过1-(5-羟基苯并噻吩-2-基)乙酮的合成得到了展示,这是一种已知的mRNA前剪接调节剂。
Iodolopyrazolium Salts: Synthesis, Derivatizations, and Applications
作者:Andreas Boelke、Thomas J. Kuczmera、Lucien D. Caspers、Enno Lork、Boris J. Nachtsheim
DOI:10.1021/acs.orglett.0c02593
日期:2020.9.18
The synthesis of iodolopyrazolium triflates via an oxidative cyclization of 3-(2-iodophenyl)-1H-pyrazoles is described. The reaction is characterized by a broad substrate scope, and various applications of these novel cyclic iodolium salts acting as useful synthetic intermediates are demonstrated, in particular in site-selective ring openings. This was finally applied to generate derivatives of the
An efficient method for the synthesis of (E)-1H-inden-1-ones using gold-catalyzed tandem [3,3]-propargyl esterrearrangement followed by Michael addition under mild reaction conditions has been developed. The resulting products are important frameworks found in numerous natural products and pharmaceutically active compounds, as well as being valuable intermediates in organic synthesis.
已开发了一种有效的方法,该方法使用金催化的串联[3,3]-炔丙基酯重排,然后在温和的反应条件下进行迈克尔加成,来合成(E)-1 H -inden-1-one。所得产物是在许多天然产物和药物活性化合物中发现的重要构架,并且是有机合成中的有价值的中间体。
Palladium-Catalyzed Internal Nucleophile-Assisted Hydration–Olefin Insertion Cascade: Diastereoselective Synthesis of 2,3-Dihydro-1<i>H</i>-inden-1-ones
作者:Perumal Vinoth、Subbiah Nagarajan、C. Uma Maheswari、Arumugam Sudalai、Vittorio Pace、Vellaisamy Sridharan
DOI:10.1021/acs.orglett.6b01623
日期:2016.7.15
novel palladium-catalyzed hydration–olefin insertion cascade assisted by internal nucleophiles was developed for the synthesis of biologically significant 2,3-dihydro-1H-inden-1-ones under mild conditions. A detailed mechanistic study revealed that the assistance of the internal nucleophiles is crucial to trigger the cascade reaction via nucleopalladation of the alkyne moiety. The overall reaction is
Palladium(II)‐Catalyzed Direct Access to Indeno[1,2‐
<i>c</i>
]isochromen‐5(11
<i>H</i>
)‐Ones via Intramolecular Oxypalladation‐Initiated Cascade Process
作者:Muthu Karuppasamy、B. S. Vachan、Tanvi Jandial、Sesuraj Babiola Annes、Nattamai Bhuvanesh、C. Uma Maheswari、Vellaisamy Sridharan
DOI:10.1002/adsc.202000456
日期:2020.7.16
A palladium(II)‐catalyzedcascade approach was established for the synthesis of indeno[1,2‐c ]isochromen‐5(11H )‐ones starting from 2‐alkynyl tert‐butyl benzoates bearing a pendant α,β‐unsaturated carbonyl moiety in high yields (up to 99%) under mild conditions. This strategy offered high atom and step economy by delivering isobutene as the only side product, and by generating two new bonds and two
建立了钯(II)催化的级联方法,用于合成带有[α,β-不饱和羰基]侧基的2-炔基叔丁基苯甲酸酯,从而合成茚并[1,2 - c ]异色素n-5(11 H)-酮。在温和的条件下以高收率(高达99%)收割。该策略通过提供异丁烯作为唯一的副产物,并在一次合成操作中生成两个新的键和两个环,从而提供了高原子和步进经济性。可以看到级联过程的机理,包括顺序的分子内氧合palpalpalation(6-endo-dig),分子内的烯烃插入和质子化步骤。
Synthesis of 3-substituted isoindolin-1-ones via a palladium-catalysed 3-component carbonylation/amination/Michael addition process
A novel palladium-catalysed three component cascade process is described involving carbonylation of an aryl iodide to generate an acyl palladium species which is intercepted by a primary aliphatic/aromatic amine, amide or sulfonamide followed by intramolecular Michael addition to afford 3-substituted isoindolin-1-ones in good yield.