Acceleration of the Dakin Reaction by Trifluoroacetic Acid
作者:Arun D. Natu、Ameya S. Burde、Rohan A. Limaye、Madhusudan V. Paradkar
DOI:10.3184/174751914x14014814873316
日期:2014.6
An acceleration of the Dakin reaction caused by addition of trifluoroaceticacid is described. The modified protocol converts aromatic aldehydes to the corresponding phenols within 4 hours at room temperature by means of hydrogen peroxide in acidic medium. This acceleration is attributed to the stability of hydrogen peroxide in an acidic medium. This modified protocol provides alternative and easy
The Baeyer-Villiger Oxidation of Aromatic Aldehydes and Ketones with Hydrogen Peroxide Catalyzed by Selenium Compounds. A Convenient Method for the Preparation of Phenols
作者:Ludwik Syper
DOI:10.1055/s-1989-27183
日期:——
A series of organoselenium compounds was investigated as activators of hydrogen peroxide in the Baeyer-Villiger oxidation. As a result, a convenient and cheap method for transformation of aromatic aldehydes, having polycondensed ring systems or electron-donating substituents, and polymethoxy derivatives of acetophenone, into phenols was elaborated. This method utilizes hydrogen peroxide activated by areneseleninic acids, as oxidizing agent.
Switchable cascade C–H annulation to polycyclic pyryliums and pyridiniums: discovering mitochondria-targeting fluorescent probes
作者:Xingyu Chen、Lipeng Yan、Yanhong Liu、Yudong Yang、Jingsong You
DOI:10.1039/d0cc06997c
日期:——
cascade triple C–H annulation of 4-hydroxy-1-naphthaldehydes with alkynes, in which six chemical bonds are formed in one-pot. This reaction enables the rapid assembly of diverse polycyclic pyrylium and pyridinium fluorophores, which leads to two specific mitochondria-labeling reagents with low cytotoxicity and superior photostability.
2-Alkoxyarenol-derived orthoquinols in carbon–oxygen, carbon–nitrogen and carbon–carbon bond-forming reactions
作者:Stéphane Quideau、Laurent Pouységu、Mayalen Oxoby、Matthew A Looney
DOI:10.1016/s0040-4020(00)00939-x
日期:2001.1
Silylated oxygen- and nitrogen-tethered orthoquinol acetates, generated by phenyliodine(III) diacetoxy-mediated oxidative acetoxylation of 2-alkoxyphenols in CH2Cl2 can be used to furnish regioselectively benzannulated heterocycles. Oxidative activation of 2-alkoxynaphthols with non-nucleophilic phenyliodine(III) bis(trifluoroacetoxy) in the presence of carbon nucleophiles, including oxidation sensitive silyl enol ethers, constitute a potentially valuable route to naturally occurring vicinally oxygenated benz[a]anthracene motifs. (C) 2000 Elsevier Science Ltd. All rights reserved.
Structure–affinity studies for a novel series of homochiral naphtho and tetrahydronaphtho analogues of α1 antagonist WB-4101
A number of enantiomeric pairs of naphthodioxane, tetrahydronaphthodioxane and naphthoxy analogues of WB-4101 (1) were designed and synthesized in order to improve the selectivity profile of the parent compound, hopefully in favour of the alpha(1a)-AR with respect to the other two alpha(1), subtypes and the 5-HT1A receptor. The new compounds 2-8 and, in addition, the two enantiomers of 1 were tested in binding assays on the alpha(1a)-AR, alpha(1b)-AR, alpha(1d)-AR, and the 5-HT1A receptor. Two of them, namely the naphtho- and tetrahydronaphthodioxane derivatives (S)-2 and (S)-3, showed lower, but significantly more specific alpha(1a), affinity than (S)-1, while the two enantiomers of the 2-methoxy-1-naphthoxy analogue 6 maintained most of the very high alpha(1a) affinity of (S)-1 and its alpha(1a) versus alpha(1b) selectivity slightly increasing the alpha(1a)/alpha(1d) and alpha(1a)/5HT(1A) affinity ratios. The SAR data were evaluated in the light of known alpha(1), subtype pharmacophores and of the alpha(1a)-AR binding mode of WB-4101 resultant from literature mutagenesis studies disclosing some interesting consonances with these models. (C) 2004 Elsevier Ltd. All rights reserved.