Results 161 to 170 of about 18,239,073 (189)

SYNTHESIS OF 5-TRICHLOROMETHYL-1,2,4-THIADIAZOLES BY 1,-3-DIPOLAR CYCLOADDITION OF NITRILE SULPHIDES TO TRICHLOROACETONITRILE

Phosphorous and Sulfur and the Related Elements, 1986
Abstract Nitrile sulphides, generated by thermal decarboxylation of 1,3,4-oxathiazol-2-ones, undergo 1,3-dipolar cycloaddition to trichloroacetonitrile yielding 5-trichloromethyl-1,2,4-thiadiazoles (45-66%). The reaction of the cycloadducts with secondary amines has also been examined.
Derek J. Greig, Michael McPherson, R. Michael Paton, John Crosby   +3 more
openaire   +1 more source

1‐(Azidomethyl)benzotriazole and ‐5‐phenyl‐1,2,3,4‐tetrazole as 1, 3‐dipolar cycloaddition components

Journal of Heterocyclic Chemistry, 1996
Abstract1‐(Azidomethyl)benzotriazole reacts with alkynes to give mixtures of isomeric 1,2,3‐triazoles, whereas the interactions of 1‐(azidomethyl)benzotriazole and ‐5‐phenyl‐1,2,3,4‐tetrazole with alkenes proceed regioselectively to form 1,2,3‐triazolines and/or aziridines and enamines in good yields.
Alan R. Katritzky, Clara N. Fali, Irina V. Shcherbakova, Sergei V. Verin   +3 more
openaire   +1 more source

1, 3-Dipolar cycloaddition between ethyl trifluoroacetoacetate and N-(benzylidene)methylamine N-oxide

J. Chem. Soc., Perkin Trans. 1, 1991
The 1,3-dipolar cycloaddition between ethyl trifluoroacetoacetate and N-(benzylidene)methylamine Noxide, performed in boiling toluene, leads regio- and stereo-selectively to an isoxazolidine, while the corresponding ethyl acetoacetate is found to be unreactive under the same conditions.
Jean-Pierre Bégué, Danièle Bonnet-Delpon, Thierry Lequeux   +2 more
openaire   +1 more source

Approach to regiochemistry using local softness in 1,3-dipolar cycloadditions

Journal of Computational Chemistry, 1998
The principle of hard and soft acids and bases is applied in the local sense to rationalize the regiochemistry in the cycloaddition reactions of a few typical 1,3-dipoles, in particular those with phosphorus-containing dipolarophiles. Local softnesses are calculated using density functional theory.
Asit K. Chandra, Minh Tho Nguyen
openaire   +2 more sources

Gram Scale Synthesis of (±)-Gregatin A via 1, 3-dipolar Cycloaddition Strategy

Here, we present a 6-step gram-scale synthesis of (±)-gregatin A, a fungal polyketide characterized by an alkylated furanone core origi-nally isolated from Cephalosporium gregatum. The synthetic route features an intermolecular 1,3-dipolar cycloaddition, a Mo-mediated disconnection of isoxazole skeleton, and an acid-mediated desilylation/enamine ...
Yiming Ding, Xiaoli Zhao, Chunlei Qu, Xianwen Long, Yaqiu Zhao, Xiao-Dong Yang, Haixiang Shen, Jun Deng   +7 more
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2 + 3 Dipolar cycloadditions of a monomeric thioaldehyde

The Journal of Organic Chemistry, 1986
E. Vedejs, R. G. Wilde
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Novel 1, 3-Dipolar Cycloadditions of Cyclobutene Diester Epoxides to Polycyclic Aromatic Hydrocarbons

2003
This paper announces the results of certain 1, 3-dipolar cycloadditions to polycyclic aromatic hydrocarbons (PAHs). The 1, 3-dipoles generated from cyclobutene diester epoxides thermally reacted with PAHs to give cycloadducts. This reaction demonstrated the remarkable ability of these 1, 3-dipoles to disrupt an aromatic system by adding across specific
Margetić, Davor, Butler, Douglas, N., Warrener, Ronald, N.   +2 more
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Mechanistic DFT Study of 1,3-Dipolar Cycloadditions of Azides with Guanidine

Molecules, 2023
Davor Margetić, Zoran Glasovac, Ivana Antol   +2 more
exaly  

Synthesis of Isoxazoles via [2+3]-Dipolar Cycloaddition Using Alkyne Surrogates

Synfacts, 2007
A. II, S. Dadiboyena, J. Xu
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Via [2+3]-Dipolar Cycloadditions

2002
openaire   +1 more source