Fast and efficient galvanostatic conversion of 2,4-diarylfurans into dimeric furan-2(5)-ones is now possible in one pot and good yields at room temperature in sustainable aqueous organic solvent. Recent applications of these highly desired structures demand our attention since they are a versatile alternative to acrylates in polymerization to achieve green materials. The reaction mechanism proposal, supported by density functional theory (DFT) theoretical calculations, involves furanoxy radicals, detected by electron paramagnetic resonance (EPR), as the last intermediate before a homocoupling step that affords butenolides.
View Article and Find Full Text PDFAza-Pechmann derivatives have emerged as interesting building blocks for the preparation of organic electronic devices. The development of methodologies aimed to enhance their chemical stability and modulate their physical and chemical properties constitutes an interesting goal. Here we report the synthesis of mechanically interlocked aza-Pechmann dyes with benzylic amide macrocycles, along with the study of how the mechanical bond impacts their stability, photophysical and redox properties.
View Article and Find Full Text PDFEcotoxicol Environ Saf
November 2023
Mechanochemistry and photocatalysis are emergent technologies for the remediation of polycyclic aromatic hydrocarbons (PAHs) in soils. In this work, mechanochemistry and photocatalysis are combined for pyrene degradation. The photodegradation of pyrene, when in contact with sepiolite under pressure application, is studied.
View Article and Find Full Text PDFThe commercial viability of electrochemical sensors requires high catalytic efficiency electrode materials. A sluggish reaction of the sensor's primary target species will require a high overpotential and, consequently, an excessive load of catalyst material to be used. Therefore, it is essential to understand nanocatalysts' fundamental structures and typical catalytic properties to choose the most efficient material according to the biosensor target species.
View Article and Find Full Text PDFThe adoption of new measures that preserve our environment, on which our survival depends, is a necessity. Electro-organic processes are sustainable per se, by producing the activation of a substrate by electron transfer at normal pressure and room temperature. In the recent years, a highly crescent number of works on organic electrosynthesis are available.
View Article and Find Full Text PDFA series of new (E) and (Z)-benzoyl-homoquinones have been prepared in good yield by the parent quinone-electrogenerated base (EGB) in the presence of α-bromoacetophenones or α-bromopropiophenone. The EGB, obtained when electrolysis of p-benzoquinone, or 1,4-naphthoquinone, is carried out at the reduction potential of their first voltammetric peak, conducted to electrogenerated phenacyl carbenes after halide evolution on the first obtained bromo-enolates. The stereoselectivity of the [2 + 2]cycloaddition of the carbene to the quinoid substrate is highly dependent on the electrode nature.
View Article and Find Full Text PDFAim: Parvifloron D is a natural diterpene with a broad and not selective cytotoxicity toward human tumor cells. In order to develop a targeted antimelanoma drug delivery platform for Parvifloron D, hybrid nanoparticles were prepared with biopolymers and functionalized with α-melanocyte stimulating hormone. Results/methodology: Nanoparticles were produced according to a solvent displacement method and the physicochemical properties were assessed.
View Article and Find Full Text PDFA series of novel water-soluble ammonium-terminated carbosilane dendrons containing a ferrocene unit at the focal point were synthesized, in order to combine the unique redox activity of ferrocene and the precisely designed structure of the dendrons with the aim to evaluate them as a new class of potential organometallic-based antibacterial compounds. The synthetic route is based on the initial amination of ferrocenecarboxaldehyde with carbosilane dendrons that contain allyl groups on the surface followed by reduction of the in situ prepared imine product, and the subsequent functionalization of the periphery with terminal amine groups by hydrosilylation reactions. Systems quaternized with HCl are soluble and stable in water or other protic solvents.
View Article and Find Full Text PDFThe one-pot concomitant electrochemical reduction of phenanthrenequinones (1, 2) and arenediazonium salts (3a-f) led to the formation of 1,3,4-oxadiazol-2(3H)-ones (4a-f, 5a) and dibenzo[c,e]azepines (6a-f) when N-methylformamide was used as the solvent. A new pathway, different from those previously described with other aprotic solvents, is proposed. The experimental data support a radical mechanism for the electrochemical process followed by an internal rearrangement to give the products.
View Article and Find Full Text PDF[reaction: see text] o-Quinones are transformed into the corresponding 1,3-dioxoles in a single-step process by cathodic reduction in dichloromethane.
View Article and Find Full Text PDFCyanoacetic acid is formed by cathodic reduction of CO(2) and anodic oxidation of the tetraalkylammonium salt anion; the process is conduced in acetonitrile using a divided cell with a medium porosity glass-frit diaphragm. A mechanism for this paired electrochemical reaction is proposed.
View Article and Find Full Text PDFCathodic reduction of N-(2-acyl(or aroyl)phenyl)-2,2,2,-trichloro-N-alkylacetamide at -1.2 V (vs SCE) under aprotic conditions yields 3-chloro-1,4-disubstituted-2(1H)-quinolinones (1) as the major product. When the reaction is carried out at -0.
View Article and Find Full Text PDFElectrolysis of benzylthiocyanate, benzyl chloride, p-methylbenzyl chloride, p-methoxybenzyl chloride, or toluene in acetonitrile, at platinum electrodes in a two compartments cell divided by a glass-frit diaphragm, affords 2,6-dimethyl-4-arylpyridine-3,5-dicarbonitrile as major product.
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