制备对位取代的3-苯基茚基亚芴的阳离子,以检查所得的茚基和芴基阳离子体系对抗芳构性的磁性测量的响应。的所有措施,1角1 H NMR位移,核独立化学位移(NICS(1)ZZ),和磁化率提高,Λ,所支持的双阳离子的反芳香性3A - ˚F 2+。的1角1 H NMR位移和NICS(1)ZZ结果表明,茚基环体系的抗芳香性低于芴基环体系,这与茚基单阳离子与芴基单阳离子的抗芳香性相反。在3-位上存在苯基取代基能够通过共振稳定茚基阳离子,从而降低其抗芳香性,但是即使在不存在3-苯基取代基的情况下,茚基亚芴基阳离子的茚基系统也比芴基系统的芳香性低。 。(反)芳族(去)稳定能计算,ASE支持了3-苯基茚基芴指示剂相对于未取代的茚基芴指示剂降低的抗芳香性。
Friedel-Crafts-Type Cyclodehydration of 1,3-Diphenyl-1-propanones. Kinetic Evidence for the Involvement of Dication
摘要:
The mechanism of intramolecular ketone-aromatic cyclodehydration of 1,3-diphenyl-1-propanones to give I-phenyl-1H-indenes in trifluoromethanesulfonic acid (TFSA) was investigated. The rate of the reaction of the monoprotonated diphenylpropanone increased proportionally to the acidity (H0) of the TFSA - trifluoroacetic acid matrix. This observation suggested that a species formed by a second protonation participates in the reaction. The O,O-diprotonated ketone is proposed as the true reactive intermediate. The substituent effect was also investigated.
作者:Bjarke S. Donslund、Nicolaj Inunnguaq Jessen、Giulio Bertuzzi、Maxime Giardinetti、Teresa A. Palazzo、Mette Louise Christensen、Karl Anker Jørgensen
DOI:10.1002/anie.201807830
日期:2018.10
[10+4] cycloaddition between catalytically generated amino isobenzofulvenes and electron‐deficient dienes is described. The highly stereoselective catalytic [10+4] cycloaddition exhibits a broad scope with high yields, reflecting a robust higher‐order cycloaddition. Experimental and computational investigations support a kinetic distribution of intermediate rotamers dictating the enantioselectivity, which relies
A Synthetic Cycle for Heteroarene Synthesis by Nitride Insertion**
作者:Patrick Q. Kelly、Alexander S. Filatov、Mark D. Levin
DOI:10.1002/anie.202213041
日期:2022.11.14
An osmium nitride is shown to insert nitrogen into indenes to afford isoquinolines. A syntheticcycle to regenerate the starting nitride is presented alongside mechanistic studies of each step.
氮化锇被证明可以将氮插入茚中以提供异喹啉。提出了再生起始氮化物的合成循环以及每个步骤的机理研究。
Nitrogen atom insertion into indenes to access isoquinolines
作者:Patrick Finkelstein、Julia C. Reisenbauer、Bence B. Botlik、Ori Green、Andri Florin、Bill Morandi
DOI:10.1039/d2sc06952k
日期:——
We report a convenient protocol for a nitrogen atom insertion into indenes to afford isoquinolines. The reaction uses a combination of commercially available phenyliodine(III) diacetate (PIDA) and ammonium carbamate as the nitrogen source to furnish a wide range of isoquinolines. Various substitution patterns and commonly used functional groups are well tolerated. The operational simplicity renders
我们报告了一个方便的方案,用于将氮原子插入茚中以提供异喹啉。该反应使用市售苯碘 ( III ) 二乙酸酯 (PIDA) 和氨基甲酸铵的组合作为氮源,以提供范围广泛的异喹啉。各种替代模式和常用的功能组都具有良好的耐受性。操作简单性使该协议具有广泛的适用性,并已成功扩展到环戊二烯直接相互转化为相应的吡啶。此外,该策略能够使用15 NH 4 Cl 作为商业15 N 源轻松合成15 N 标记的异喹啉。
Arylcyclopropane photochemistry. Effects of electron-donating and electron-withdrawing aromatic substituents on the photochemical rearrangements of 1,1-diarylcyclopropanes
作者:Stephen S. Hixson、Lothar A. Franke
DOI:10.1021/jo00247a008
日期:1988.6
Cobalt-Catalyzed Nitrogen Atom Insertion in Arylcycloalkenes