Results 151 to 160 of about 41,109 (281)

Alkylation and 1,3-Dipolar Cycloaddition of 6-Styryl-4,5-dihydro-2H-pyridazin-3-one: Synthesis of Novel N-Substituted Pyridazinones and Triazolo[4,3-b]pyridazinones

Journal of Chemistry, 2013
Some new N-substituted pyridazinones and triazolo[4,3-b]pyridazinones were synthesized, respectively, by simple alkylation and 1,3-dipolar cycloaddition of pyridazin-3-one with nitrile imines.
Souad Mojahidi, Hanan Sekkak, El Mostapha Rakib, Maria G. P. M. S. Neves, Maria A. F. Faustino, José A. S. Cavaleiro, Hafid Zouihri   +6 more
doaj   +1 more source

Novel 3H ‐1,2,3‐Dithiaphosphole and Unprecedented 1,3,2,4‐Dithiadiphosphinane Heterocycles: Unanticipated Cyclization Reactions of Lawesson's Reagent and Alkynes

European Journal of Organic Chemistry, Accepted Article.
Treatment of Lawesson's reagent with selected alkyl or aryl alkynes results in the formation of cyclization products such as 3H‐1,2,3‐dithiaphosphole‐3‐sulfide or unprecedented 1,3,2,4dithiadiphosphinane‐2,4‐disulfide derivatives. The new heterocycles are characterized spectroscopically and in two cases by crystal structure analyses. Density functional
Felix Blüm, Bernd Goldfuss, Holger Butenschön   +2 more
wiley   +1 more source

Synthesis of pyrrolizines by intramolecular capture of 1,4-dipolar intermediates in reactions of enamines with dimethyl acetylenedicarboxylate [PDF]

, 1981
Solvent polarity and reaction temperature strongly influence the reactions of dimethyl acetylenedicar-boxylate (DMAD) with 1-pyrrolidinyl enamines of acyclic and cyclic ketones. Whereas DMAD and 1-[1-phenyl-2-(phenylthio)ethenyl]pyrrolidine (3) give only
Harkema, S., Hummel, G.J. van, Reinhoudt, D.N., Trompenaars, W.P., Verboom, W., Visser, G.W.   +5 more
core   +3 more sources

Crystal structure of (2R*,3aR*)-2-phenylsulfonyl-2,3,3a,4,5,6-hexahydropyrrolo[1,2-b]isoxazole

Acta Crystallographica Section E: Crystallographic Communications, 2017
The title compound, C12H15NO3S, was prepared by 1,3-dipolar cycloaddition of 3,4-dihydro-2H-pyrrole 1-oxide and phenyl vinyl sulfone. In the molecule, both fused five-membered rings display a twisted conformation.
Yaiza Hernández, Isidro Marcos, Narciso M. Garrido, Francisca Sanz, David Diez   +4 more
doaj   +1 more source

Stereoselective Ag-Catalyzed 1,3-Dipolar Cycloaddition of Activated Trifluoromethyl-Substituted Azomethine Ylides.

Chemistry, 2016
A silver-catalyzed 1,3-dipolar cycloaddition of fluorinated azomethine ylides and activated olefins is reported. The reaction offers a straightforward and atom-economical procedure for the preparation of fluorinated pyrrolidines.
Alberto Ponce, I. Alonso, J. Adrio, J. Carretero   +3 more
semanticscholar   +1 more source

The Quinoline Photoremovable Group (PPG) Platform—A Medicinal Chemist's Approach for Photocage Development and Applications

Medicinal Research Reviews, EarlyView.
ABSTRACT Photoremovable protecting groups (PPGs) offer a straightforward solution for the temporary inactivation of biologically active substrates and their subsequent controlled release by light irradiation. Their relatively easy design and mode of application have made them useful tools for studying dynamic biological processes in vitro and in vivo ...
Bence Kontra, Zoltán Mucsi, Janez Ilaš, Petra Dunkel   +3 more
wiley   +1 more source

A Systematic Review of Synthetic and Anticancer and Antimicrobial Activity of Quinazoline/Quinazolin‐4‐one Analogues

ChemistryOpen, EarlyView.
Quinazoline represents an important class of heterocycles with diverse medicinal and pharmacological significance. This review systematically examines scholarly efforts toward understanding different synthetic pathways emphasizing the role of metal and non‐metal catalysts including some miscellaneous reagents employed in the synthesis of quinazoline ...
Neha Manhas, Gobind Kumar, Sanjeev Dhawan, Talent Makhanya, Parvesh Singh   +4 more
wiley   +1 more source

Synthesis of 1,2,3-Triazole 5-Chloroisatin Derivatives via Copper-Catalyzed 1,3-Dipolar Cycloaddition Reactions [PDF]

, 2017
A facile and simple protocol for the ‘Click\u27 cycloaddition of organic azides with N-propargylchloroisatine catalyzed by CuI, produces in good yields novel of 1,4-disubstituted 1,2,3-triazoles were obtained.
Rodi, Y. K. (Y), Senhaji, O. (O), Skalli, M. K. (M), Tribak, Z. (Z)   +3 more
core   +1 more source

Diethyl 4-acetyl-5-(2-nitrophenyl)pyrrolidine-2,2-dicarboxylate

Acta Crystallographica Section E, 2010
The title compound, C18H22N2O7, was synthesized by the 1,3-dipolar cycloaddition reaction of but-3-en-2-one, diethyl 2-aminomalonate and 2-nitrobenzaldehyde. In the molecule, the pyrrolidine ring possesses an envelope conformation.
Long He
doaj   +1 more source

Visible-Light-Mediated Anti-Regioselective Nitrone 1,3-Dipolar Cycloaddition Reaction and Synthesis of Bisindolylmethanes.

Organic Letters, 2017
The development of photoredox reactions of 1,3-dipolar cycloaddition of nitrones with alkenes is reported. It offers an efficient synthetic method to obtain isoxazolidine derivatives under mild conditions in synthetically useful yields.
Lewei Zheng, Fei Gao, C. Yang, Guo-Lin Gao, Yating Zhao, Yuan Gao, W. Xia   +6 more
semanticscholar   +1 more source