Results 31 to 40 of about 2,089,289 (186)

Diels–Alder reactions in confined spaces: the influence of catalyst structure and the nature of active sites for the retro-Diels–Alder reaction

Beilstein Journal of Organic Chemistry, 2016
Diels–Alder cycloaddition between cyclopentadiene and p-benzoquinone has been studied in the confined space of a pure silica zeolite Beta and the impact on reaction rate due to the concentration effect within the pore and diffusion limitations are ...
Ángel Cantín, M. Victoria Gomez, Antonio de la Hoz   +2 more
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Cycloaddition Reaction

, 2020
1,3-Dipolar cycloaddition reaction between organic azide and metal carbyne is a useful strategy to construct metallacycles. However, the electronic behavior of organic azide in 1,3-dipolar cycloaddition reactions is less explored.
Zhenyang Lin, Lu, Zhengyu, Fu Kit Sheong, Zhang, Hong, Zhengyu Lu, Sheong, Fu Kit, Zhang, Jing Xuan, Hong Zhang, Lin, Zhenyang, Jing‐Xuan Zhang   +9 more
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Incorporation of Spin Labels and Paramagnetic Tags for Magnetic Resonance Studies Using Cycloaddition Reactions as a Tool

Reactions
The cycloaddition reaction is one of the most common reactions in organic chemistry. It has been applied in various fields. Herein, we focus on the application of cycloaddition reactions in investigating biological molecules and materials using magnetic ...
Amarendra Nath Maity, Amiya Kumar Medda, Shyue-Chu Ke   +2 more
doaj   +1 more source

Enantioselective cycloaddition reactions

ChemInform, 1991
Publisher Summary This chapter reviews the cycloadditions reactions because they are popular, widely used, and also constitutes enormous body of chemistry. The chapter focuses on the landmark achievements as well as state-of-the-art examples of relevant chemistry.
openaire   +2 more sources

1,2,4-Oxadiazoles from cycloreversions of oxadiazabicyclo[3.2.0]heptenes: 1-azetines as thiocyanate equivalents [PDF]

, 2013
1,3-Dipolar cycloaddition of nitrile oxides to 4-aryl-2-alkylthio-1-azetines gave a series of oxadiazabicyclo[3.2.0]heptenes as single diastereoisomers. Heating these cycloadducts in toluene resulted in an overall [2+2]-cycloreversion to give 5-alkylthio-
Khan, Musharraf, Khan, Musharraf N., O'Gorman, Paul A., Pitard, Arnaud, Hemming, Karl, O'Gorman, P.A.   +5 more
core   +1 more source

Unveiling the Chemistry of Higher-Order Cycloaddition Reactions within the Molecular Electron Density Theory

Chemistry, 2022
The higher-order cycloaddition (HOCA) reaction of tropone with cyclopentadiene (Cp) has been studied within the Molecular Electron Density Theory.
Luis R. Domingo, Mar Ríos-Gutiérrez, Patricia Pérez   +2 more
doaj   +1 more source

Promotion mechanism of hydroxyl groups in catalyzing CO2 cycloaddition

Journal of CO2 Utilization
In this study, a series of hydroxy-functionalized quaternary ammonium salt catalysts, i.e., NEt3(HE)Br, NEt2(HE)2Br, NEt1(HE)3Br, and N(HE)4Br, were successfully prepared by quantitatively grafting hydrogen-bond donors (HBDs) as electrophilic sites on ...
Yiming Wang, Wensheng Wei, Yuxin Wang, Guangwen Xu, Jinggang Zhao, Lei Shi   +5 more
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[2+2+2] Cycloaddition Reactions of Macrocyclic Systems Catalyzed by Transition Metals. A Review

Molecules, 2010
Polyalkyne and enediyne azamacrocycles are prepared from arenesulfonamides and various alkyne and alkene derivatives either under basic or neutral conditions.
Anna Roglans, Anna Pla-Quintana
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Microwave-Assisted Regioselective Synthesis and 2D-NMR Studies of New 1,2,3-Triazole Compounds Derived from Acridone

Journal of Chemistry, 2021
A simple and mild protocol towards the synthesis of new 1,2,3-triazole compounds derived from acridone has been developed via regiospecific 1,3-dipolar cycloaddition reaction between 10-(prop-2-yn-1-yl)acridone derivatives and aromatic azides using CuI ...
Mohammed Aarjane, Siham Slassi, Bouchra Tazi, Amina Amine   +3 more
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The Puzzle of the New Type of Intermediate in the Course of [2 + 2] Cycloaddition with the Participation of Conjugated Nitroalkenes: MEDT Computational Study

Molecules
The phenomena of regio- and stereoselectivity and the molecular mechanism of the [2 + 2] cycloaddition reaction between (E)-2-arylnitroethenes and the ynamine molecular system were analyzed using wb97xd/6-311 + G(d) (PCM) quantumchemical calculations. It
Radomir Jasiński, Agnieszka Kącka-Zych
doaj   +1 more source