Results 31 to 40 of about 2,202,700 (266)

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
doaj   +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

Iron-Catalyzed Cycloaddition Reaction of Diynes and Cyanamides at Room Temperature

, 2013
An iron-catalyzed [2 + 2 + 2] cycloaddition reaction of diynes and cyanamides at room temperature is reported. Highly substituted 2-aminopyridines were obtained in good to excellent yields with high regioselectivity.
Wan, Boshun, Xu, Fen, Pan, Bin, 万伯顺, Wang, Dongping, Wang, Chunxiang   +5 more
core   +1 more source

[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
doaj   +1 more source

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
doaj   +1 more source

Synthetic studies on the bioactive tetramic acid JBIR-22 using a late stage Diels-Alder reaction [PDF]

, 2015
The authors would like to thank the following for funding: Cancer Research UK (grants C21383/A6950 and C483/A10706)A late stage Diels-Alder reaction is used to prepare a mixture of JBIR-22, a natural product from the Equisetin family of tetramic acids ...
Healy, A. R., Westwood, Nicholas James, Westwood, Nicholas James; id_orcid   +2 more
core   +1 more source

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

[4 + 2]-Cycloadditions to 1 '-Phenyl-Substituted 3-Vinylindoles with N-Phenylmaleimide: An Access to New [a]Anellated Carbazole Derivatives

CHIMIA, 1987
The AlCl3-catalyzed [4 + 2]-cycloaddition of T-phenyl-substituted 3-vinylindoles with N-phenylmaleimide gives rise to new anellated carbazole derivatives with a high endo-preference.
Ludwig Pfeuffer, Ulf Pindur
doaj   +1 more source

Heterocyclic syntheses involving cycloaddition reactions

, 2021
Heterocyclic syntheses involving cycloaddition ...
Khamis F. Shuhaibar (11170513)
core   +1 more source

Highly Regioselective Construction of Spirocycles via Phosphine-Catalyzed [3 + 2]-Cycloaddition

, 2016
A direct entry to spirocycles with low to moderate regioselectivity was achieved by triphenylphosphine-catalyzed [3 + 2]-cycloaddition of active exo-methylenecycles (1) and ethyl 2,3-butadienoate (2).
Xiyan Lu (1470865), Yihua Yu (399736), Yishu Du (2683537)   +2 more
core   +1 more source