scholarly journals Synthesis of Methoxy-Substituted Phenols by Peracid Oxidation of the Aromatic Ring.

ChemInform ◽  
2006 ◽  
Vol 37 (1) ◽  
Author(s):  
Hans-Rene Bjoersvik ◽  
Giovanni Occhipinti ◽  
Cristian Gambarotti ◽  
Leonardo Cerasino ◽  
Vidar R. Jensen
Keyword(s):  
Aromatic Ring ◽  
Substituted Phenols

Synthesis of Methoxy-Substituted Phenols by Peracid Oxidation of the Aromatic Ring

2005 ◽  
Vol 70 (18) ◽  
pp. 7290-7296 ◽  
Author(s):  
Hans-René Bjørsvik ◽  
Giovanni Occhipinti ◽  
Cristian Gambarotti ◽  
Leonardo Cerasino ◽  
Vidar R. Jensen
Keyword(s):  
Aromatic Ring ◽  
Substituted Phenols

scholarly journals 3-Pyridinols and 5-pyrimidinols: Tailor-made for use in synergistic radical-trapping co-antioxidant systems

2013 ◽  
Vol 9 ◽  
pp. 2781-2792 ◽  
Author(s):  
Luca Valgimigli ◽  
Daniele Bartolomei ◽  
Riccardo Amorati ◽  
Evan Haidasz ◽  
Jason J Hanthorn ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Aromatic Ring ◽  
Kinetic Data ◽  
Peroxyl Radicals ◽  
Antioxidant Systems ◽  
Phenolic Antioxidants ◽  
Substituted Phenols ◽  
Radical Trapping ◽  
Insight Into

The incorporation of nitrogen atoms into the aromatic ring of phenolic compounds has enabled the development of some of the most potent radical-trapping antioxidants ever reported. These compounds, 3-pyridinols and 5-pyrimidinols, have stronger O–H bonds than equivalently substituted phenols, but possess similar reactivities toward autoxidation chain-carrying peroxyl radicals. These attributes suggest that 3-pyridinols and 5-pyrimidinols will be particularly effectiveco-antioxidants when used in combination with more common, but less reactive, phenolic antioxidants such as 2,6-di-tert-butyl-4-methylphenol (BHT), which we demonstrate herein. The antioxidants function in a synergistic manner to inhibit autoxidation; taking advantage of the higher reactivity of the 3-pyridinols/5-pyrimidinols to trap peroxyl radicals and using the less reactive phenols to regenerate them from their corresponding aryloxyl radicals. The present investigations were carried out in chlorobenzene and acetonitrile in order to provide some insight into the medium dependence of the synergism and the results, considered with some from our earlier work, prompt a revision of the H-bonding basicity value of acetonitrile to β2 H of 0.39. Overall, the thermodynamic and kinetic data presented here enable the design of co-antioxidant systems comprising lower loadings of the more expensive 3-pyridinol/5-pyrimidinol antioxidants and higher loadings of the less expensive phenolic antioxidants, but which are equally efficacious as the 3-pyridinol/5-pyrimidinol antioxidants alone at higher loadings.

Separation of close boiling substituted phenols by dissociation extraction

1981 ◽  
Vol 31 (1) ◽  
pp. 279-284 ◽  
Author(s):  
Vishwas V. Wadekar ◽  
Man Mohan Sharma
Keyword(s):  
Substituted Phenols

Quantitative Structure-Property Relationship (QSPR) Study of the Hydrophobicity of Phenols and 2-(Aryloxy-a-acetyl)-phenoxathiin Derivatives

2008 ◽  
Vol 59 (11) ◽  
Author(s):  
Adrian Beteringhe ◽  
Ana Cristina Radutiu ◽  
Titus Constantinescu ◽  
Luminita Patron ◽  
Alexandru T. Balaban
Keyword(s):  
Water Solubility ◽  
Molecular Descriptors ◽  
Log P ◽  
Structure Property ◽  
Substituted Phenols ◽  
Reverse Phase ◽  
Aromaticity Index ◽  
Structure Property Relationship ◽  
Layer Chromatography ◽  
Energy Of Formation

In a preceding study, the molecular hydrophobicity (RM0) was determined experimentally from reverse-phase thin-layer chromatography data for several substituted phenols and 2-(aryloxy-a-acetyl)-phenoxathiin derivatives, obtained from the corresponding phenoxides and 2-(a-bromoacetyl)-phenoxathiin. QSPR correlations for RM0 were explored using four calculated molecular descriptors: the water solubility parameter (log Sw), log P, the Gibbs energy of formation (DGf), and the aromaticity index (HOMA). Triparametric correlations do not improve substantially the biparametric correlation of RM0 in terms of log Sw and HOMA.

Photoreaction of N-butyl 3,4-dimethoxy-6-nitrobenzamide with butylamine. A model study for lysine-directed photoaffinity labelling

1987 ◽  
Vol 52 (7) ◽  
pp. 1780-1785 ◽  
Author(s):  
Petr Kuzmič ◽  
Libuše Pavlíčková ◽  
Milan Souček
Keyword(s):  
Nitro Group ◽  
Aromatic Ring ◽  
Ultraviolet Irradiation ◽  
Title Compound ◽  
Reductive Coupling ◽  
Photoaffinity Labelling ◽  
Photolysis Rate ◽  
Model Study ◽  
A Minor

Ultraviolet irradiation of the title compound I in the presence of butylamine gave predominantly products of nucleophilic photosubstitution by the amine, i.e., nitroanilines IIa and IIb. Besides, small amounts of products of hydrolysis (phenol III) and reductive coupling (azoxybenzene IV) were also formed. Comparison of the overall photolysis rate of I with that of 3,4-dimethoxy-1-nitrobenzene (V) indicates a minor loss of reactivity, most probably due to some deviation from coplanarity of the activating nitro group and the aromatic ring.

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