Results 31 to 40 of about 8,043 (225)

Site-Selective Modification of a Porpholactone—Selective Synthesis of 12,13- and 17,18-Dihydroporpholactones

Molecules, 2020
The reaction of meso-tetrakis(pentafluorophenyl)porpholactone with azomethine ylides and nitrones affords pyrrolidine-fused and isoxazolidine-fused dihydroporpholactones that display, respectively, isobacteriochlorin- and chlorin-type UV–Vis spectra ...
Ana F. R. Cerqueira, Gustautas Snarskis, Jonas Zurauskas, Samuel Guieu, Filipe A. Almeida Paz, Augusto C. Tomé   +5 more
doaj   +1 more source

On the strong difference in reactivity of acyclic and cyclic diazodiketones with thioketones: experimental results and quantum-chemical interpretation [PDF]

, 2015
The 1,3-dipolar cycloaddition of acyclic 2-diazo-1,3-dicarbonyl compounds (DDC) and thioketones preferably occurs with Z,Econformers and leads to the formation of transient thiocarbonyl ylides in two stages.
Holleman, Huisgen, Korobizina, Mlostoń, Mlostoń, Mlostoń, Nikolaev, Nikolaev, Zollinger   +8 more
core   +4 more sources

Nitrile Oxide, Alkenes, Dipolar Cycloaddition, Isomerization and Metathesis Involved in the Syntheses of 2-Isoxazolines

Molecules, 2023
The involvement of 1,3-dipolar cycloaddition (1,3-DP), double bond migration, metathesis, and nitrile oxide (including in situ-generated nitrile oxide) as dipoles, together with the C=C bond containing dipolarophiles, in the syntheses of 2-isoxazolines ...
Stanisław Krompiec, Piotr Lodowski, Aneta Kurpanik-Wójcik, Bogumiła Gołek, Angelika Mieszczanin, Aleksandra Fijołek, Marek Matussek, Klaudia Kaszuba   +7 more
doaj   +1 more source

X=Y–ZH compounds as potential 1,3-dipoles. Part 64: Synthesis of highly substituted conformationally restricted and spiro nitropyrrolidines via Ag(I) catalysed azomethine ylide cycloadditions [PDF]

, 2008
1,3-Dipolar reactions of imines of both acyclic and cyclic α-amino esters with a range of nitroolefins using a combination of AgOAc or Ag2O with NEt3 are described.
Albert, Amornraksa, Ayerbe, Becker, Berger, Bourguignon, Bryce, Cecilia Orgaz de la Cierva, Colin Kilner, Crooks, Dondas, Díaz-Ortiz, Fejes, Fejes, Gentles, Grigg, Grigg, Grigg, Grigg, Grigg, Grigg, Grigg, Grigg, Grigg, H. Ali Dondas, Hill, Kabalka, Krapcho, Lee, Mohammed A.B. Sarker, Nielson, Norman, Nyerges, Nyerges, Nyerges, Nyerges, Nyerges, Pak, Peterli, Pinna, Poornachandran, Poornachandran, Poornachandran, Ram, Rang, Ronald Grigg, Sader-Bakaouni, Shorter, Song, Thurkauf, Vivanco, Yan   +51 more
core   +1 more source

Copper nanoparticles on controlled pore glass (CPG) as highly efficient heterogeneous catalysts for “click reactions”

Scientific Reports, 2020
We herein report that supported copper nanoparticles (CuNPs) on commercially available controlled pore glass (CPG), which exhibit high mechanical, thermal and chemical stability as compared to other silica-based materials, serve as a useful heterogeneous
Abdolrahim A. Rafi, Ismail Ibrahem, Armando Córdova   +2 more
doaj   +1 more source

Concerted [4 + 2] and Stepwise (2 + 2) Cycloadditions of Tetrafluoroethylene with Butadiene: DFT and DLPNO-UCCSD(T) Explorations. [PDF]

, 2020
Tetrafluoroethylene and butadiene form the 2 + 2 cycloadduct under kinetic control, but the Diels-Alder cycloadduct is formed under thermodynamic control. Borden and Getty showed that the preference for 2 + 2 cycloaddition is due to the necessity for syn-
Houk, KN, Liu, Peng, Mackey, Joel L, Pemberton, Ryan P, Svatunek, Dennis   +4 more
core  

Isolation of bis(copper) key intermediates in Cu-catalyzed azide-alkyne "click reaction". [PDF]

, 2015
The copper-catalyzed 1,3-dipolar cycloaddition of an azide to a terminal alkyne (CuAAC) is one of the most popular chemical transformations, with applications ranging from material to life sciences.
Bertrand, Guy, Jin, Liqun, Melaimi, Mohand, Tolentino, Daniel R   +3 more
core   +2 more sources

Solvent-Free 1,3-Dipolar Cycloadditions of Nitrones for a More Sustainable Synthesis of Glycomimetics

Reactions
1,3-Dipolar cycloadditions on nitrone dipoles are key reactions to access five-membered heterocycles, which are useful intermediates in the synthesis of biologically relevant glycomimetics.
Debora Pratesi, Alessio Morano, Andrea Goti, Francesca Cardona, Camilla Matassini   +4 more
doaj   +1 more source

Iridium-Catalyzed 1,3-Dipolar Cycloadditions [PDF]

, 2010
The authors thank financial support from Ministerio de Ciencia e Innovación (MICINN, Spain) and FEDER (Grant CTQ2009/10303BQU) and MULTICAT, Consolider Ingenio- 2010 (CSD2009-00050).
Carmona, Daniel, Oro, Luis A.
openaire   +2 more sources

A Convenient Synthesis of Novel Isoxazolidine and Isoxazole Isoquinolinones Fused Hybrids

Molecules, 2023
Isoxazolidine, isoxazole, and isoquinolinone rings are present in the structure of several natural products and/or pharmaceutically interesting compounds.
Konstantinos A. Ouzounthanasis, Stergios R. Rizos, Alexandros E. Koumbis   +2 more
doaj   +1 more source