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Mono, Di and Trifunctional Cyclic Organic Peroxides: The Effect of Substituents and Ring Size on their Thermolysis in 1,4-dioxan
(Csiro Publishing, 2013-07-15)
The thermal decomposition reaction of cyclic organic peroxides was studied in 1,4-dioxan at initial concentrations between ~10–4 and 10–2 mol L–1 and at a temperature interval between 100 and 170°C, according to the thermal ...
Understanding the role played by protic ionic liquids (PILs) and the substituent effect for enhancing the generation of Z -cinnamic acid derivatives
(Royal Society of Chemistry, 2020-04)
Photoisomerization of a series of substituted E-cinnamic acids in MeCN in their acid forms and as their corresponding protic ionic liquids (PILs) with light of 300 nm is studied. The nature, strength, number, and position ...
Nickel alpha-Keto-beta-Diimine Initiators for Olefin Polymerization
(WILEY-V C H VERLAG GMBH, 2009)
(Figure Presented) A new ligand-metal combination (see picture, Ni green, Br brown, N blue, O red, C gray) was designed to be cationic and to benefit from removal of electron density by the action of a Lewis acid on the ...
Effect of different C3-aryl substituents on the antioxidant activity of 4-hydroxycoumarin derivatives
(Pergamon-Elsevier Science Ltd, 2011-11)
The antioxidant activity of 4-hydroxycoumarin synthetic derivatives and 4-methylumbelliferone were determined taking 4-hydroxycoumarin as the reference compound. Six 3-aryl-4-hydroxycoumarin derivatives were synthesized ...
Analysis of Tautomerism in beta-Ketobutanamides by Nuclear Magnetic Resonance: Substituent, Temperature and Solvent Effects
(Lifescience Global, 2012-08)
β-ketoamides are versatile intermediates for the synthesis of several heterocycles and they are also relevant compounds in biological systems, with their tautomeric equilibria being a crucial aspect to be studied in order ...
Atropisomerism in amidinoquinoxaline N-oxides: effect of the ring size and substituents on the enantiomerization barriers
(American Chemical Society, 2015-01)
The atropisomerism of novel 2,3-dihydro1H-pyrimido[1,2-a]quinoxaline 6-oxides 1 bearing dissymmetric (ortho-substituted) 5-aryl residues and the homologous 1,2-dihydroimidazo[1,2-a]quinoxaline 5-oxides 2 was investigated. ...
Photoswitchable fluorescent diheteroarylethenes: substituent effects on photochromic and solvatochromic properties
(Royal Society of Chemistry, 2014-01)
Photoswitchable fluorescent diheteroarylethenes are promising candidates for applications in super-resolution molecular localization fluorescence microscopy thanks to their high quantum yields and fatigue-resistant ...
Substituent effects on NMR spectroscopy of 2,2-dimethylchroman-4-one derivatives: Experimental and theoretical studies
(Molecular Diversity Preservation International, 2020-04)
The attribution of 1H and 13C NMR signals of a library of 5-, 6- and 7-substituted 2,2-dimethylchroman-4-one derivatives is reported. Substituent effects were interpreted in terms of the Hammett equation, showing a good ...
Substituent Effects on Aluminyl Anions and Derived Systems: A High-Level Theory
(2021)
Aluminyl anions are low-valent aluminum species bearing a lone pair of electrons and a negative charge. These systems have drawn recent synthetic interest for their nucleophilic nature, allowing for the activation of ...
Effect of thickness, chemical nature of dopants and an alkyl substituent on absorption bands of polyaniline
(Springer VerlagNew YorkEUA, 1998)