2,996 Results Found

Macrocyclic polymers present an important class of macromolecules, displaying the reduced radius of gyration or impossibility to entangle. A rare approach for their synthesis is the ring expansion-controlled radical “vinyl” polymerization...

With the rapid development of radical initiation technologies such as photocatalysis and electrocatalysis, radical reactions have become an increasingly attractive approach for constructing target molecules. However, designing efficient synthetic rou...

Radical reactions in water or aqueous media are important for organic synthesis, realizing high-yielding processes under non-toxic and environmentally friendly conditions. This overview includes (i) a general introduction to organic chemistry in wate...

Titanium complexes have been widely used as catalysts for C‑C bond-forming processes via free-radical routes. Herein we provide an overview of some of the most significant contributions in the field, that covers the last decade, emphasizing the key r...

Nitrogenous compounds have been extensively utilized as hydrogen atom transfer (HAT) catalysts in photoredox reactions, with nitrogenous radical cations being the actual hydrogen atom abstractors. Building upon our previous work, 120 thermodynamic gr...

Secondary reactions in radical polymerization pose a challenge when creating kinetic models for predicting polymer structures. Despite the high impact of these reactions in the polymer structure, their effects are difficult to isolate and measure to...

In this investigation, a multifunctional visible-light TX-based photosensitizer containing a siloxane moiety (TXS) was designed with a good overall yield of 54%. The addition of a siloxane moiety enabled the incorporation of a TX photosensitizer into...

Recently, the radical ring-opening polymerization of cyclic monomers has become one of the most important topics because it can impart degradability to vinyl polymers by introducing functional groups and heteroatoms into the main chain through copoly...

The exhaustion of conventional light oils necessitates the shift towards unconventional sources such as biomass, heavy oil, oil shale, and coal. Non-catalytic thermal cracking by a free radical mechanism is at the heart of the upgrading, prior to ref...

Defining the copper-based catalysts that are responsible for the catalytic behaviour of oil-paper insulation systems and implementing effective regulation are of great significance. Accelerated ageing experiments were conducted to reveal variations i...

Synthetic radicals have intrinsic power for cascading and multifunctional reactions to construct diverse molecular scaffolds. In the previous review series, we covered 1,2-difunctionalizations, remote 1,3-, 1,4-, 1,5-, 1,6-, and 1,7-difunctionalizati...

In this mini-review, we present our concepts for designing multicomponent reactions with reference to a series of sequential radical reactions that we have developed. Radical reactions are well suited for the design of multicomponent reactions due to...

Honokiol is a natural bisphenol neolignan present in the bark of Magnolia officinalis, whose extracts have been employed in oriental medicine to treat several disorders, showing a variety of biological properties, including antitumor activity, potent...

The chlorothiophenoxy radicals (CTPRs) are key intermediate species in the formation of polychlorinated dibenzothiophenes/thianthrenes (PCDT/TAs). In this work, the formation of CTPRs from the complete series reactions of 19 chlorothiophenol (CTP)...

Radical transformations are powerful in organic synthesis for the construction of molecular scaffolds and introduction of functional groups. In radical difunctionalization reactions, the radicals in the first functionalized intermediates can be reloc...

Microchannel burners suffer from low combustion efficiency and poor stability in applications. In order to explore the effect of wall reaction on methane/air premixed combustion performances in the microchannel, the effects of wall activity, inlet ve...

Radical reactions are powerful in the synthesis of diverse molecular scaffolds bearing functional groups. In previous review articles, we have presented 1,2-difunctionalizations, remote 1,3-, 1,4-, 1,5-, 1,6- and 1,7-difunctionalizations, and additio...

As a starting channel, the H-intermigration reaction of alkylperoxy radicals (ROO radicals) that yields hydroperoxyl alkyl radicals (QOOH radicals) determines the low-temperature chemistry of alkanes. In this work, this type of reaction was investiga...

Consideration of the changes in free energy shows that the assumed initial steps in reactions of H2O2 with Fe2+ and Fe3+ in the free radical theory are not consistent. The free radical theory is unable to account for the Fe3+-initiated decomposition...

The concerted elimination reaction class of peroxyl-hydroperoxyl alkyl radicals (•OOQOOH) plays a crucial role in the low-temperature combustion of normal-alkyl cyclohexanes. The generation of the relatively unreactive HO2 radicals in this react...

The review covers research published since 2017 and is focused on enantioselective synthesis using radical reactions. It describes recent approaches to the asymmetric synthesis of chiral molecules based on the application of the metal catalysis, dual...

Free radical pathways play a major role in the degradation of protein pharmaceuticals. Inspired by biochemical reactions carried out by thiyl radicals in various enzymatic processes, this review focuses on the role of thiyl radicals in pharmaceutical...

In this study, transition state energy and atomic charge were calculated using the Gaussian 09 program with focus on three-ring PAHs, such as acenaphthylene and anthracene, which are most likely found in contaminated sites. The calculation results we...

Nitrophenols, hazardous environmental pollutants, react promptly with atmospheric oxidants such as hydroxyl or nitrate radicals. This work aimed to estimate how fast nitrophenols are removed from the atmosphere by the aqueous-phase reactions with sul...

Although diaryl tellurides are parent organotellurium compounds, their synthesis methods, especially for unsymmetrical ones, are limited. This may be due to the instability of diaryl tellurides and their synthesis intermediates under reaction conditi...

We have developed a photochemical ATRA/ATRC reaction that is mediated by halogen bonding interactions. This reaction is caused by the reaction of malonic acid ester derivatives containing bromine or iodine with unsaturated compounds such as alkenes a...

The reaction of hydroxyl radical (HO•) with DNA produces many primary reactive species and many lesions as final products. In this study, we have examined the optical spectra of intermediate species derived from the reaction of HO• with a v...

The free radical trapping capacities of multiple pyranoanthocyanins in wine storage and ageing were theoretically explored by density functional theory (DFT) methods. Intramolecular hydrogen bonds were detected in all pyranoanthocyanins, and the plan...

The free radical copolymerization of electron-acceptor and electron-donor vinyl monomers represents a particular case of sequence-controlled polymerization. The reactions of maleic anhydride (MA) or related compounds (acceptor comonomers) with &alpha...

Two 1,3,8,10-undecatetraenes were synthesized to test the viability of the intramolecular radical cation induced Diels-Alder reaction in the diene - diene format. Cyclization was successful only for the substituted tetraene with the lower oxidation p...

Throughout the last 25 years, computational chemistry based on quantum mechanics has been applied to the investigation of reaction kinetics in free radical polymerization (FRP) with growing interest. Nowadays, quantum chemistry (QC) can be considered...

Using electronic absorption spectra and thin layer chromatography, the reactionof 2,2-diphenyl-1-picrylhydrazyl (DPPH) with O2•–, HO•, HO–, and HOO– anions and freeradicals revealed the formation of the para-nitro- and para-hydroxy-derivatives of 2,2...

Diarylbibenzofuranone (DABBF) is a dynamic covalent bonding unit, which is in equilibrium with the corresponding radicals at room temperature, and polymers with DABBF linkages show notable properties such as self-healing. The preparation routes have...

Organic peroxy radicals (RO2) as key intermediates in tropospheric chemistry exert a controlling influence on the cycling of atmospheric reactive radicals and the production of secondary pollutants, such as ozone and secondary organic aerosols (SOA)....

The radical intermediates formed upon UVA irradiation of titanium dioxide suspensions in aqueous and non-aqueous environments were investigated applying the EPR spin trapping technique. The results showed that the generation of reactive species and t...

Novel flower-shaped C-dots/Co3O4{111} with dual-reaction centers were constructed to improve the Fenton-like reaction activity and peroxymonosulfate (PMS) conversion to sulfate radicals. Due to the exposure of a high surface area and Co3O4{111} facet...

We report on studies of reactions of singlet oxygen with carotenoids and retinoids and a range of free radical studies on carotenoids and retinoids with emphasis on recent work, dietary carotenoids and the role of oxygen in biological processes. Many...

Radical reactions are powerful in creating carbon–carbon and carbon–heteroatom bonds. Designing one-pot radical reactions with cascade transformations to assemble the cyclic skeletons with two new functional groups is both synthetically a...

Many widely-used polymers are made via free-radical polymerization. Mathematical models of polymerization reactors have many applications such as reactor design, operation, and intensification. The method of moments has been utilized extensively for...

Chemical kinetic studies of the β-scission reaction class of hydroperoxyl alkyl hydroperoxyl radicals (•P(OOH)2) from normal-alkyl cyclohexanes are carried out systematically through high-level ab initio calculations. Geometry optimizations...

The synthesis of a water soluble azo initiators from 2,2’-azodiisobutyronitrile (AIBN) was performed in three steps: reaction of dinitrile with aromatic alcohols in the presence of HCl to form bisiminoesters hydrochlorides which are hydrolyzed to the...

The DFT method was used to evaluate the adsorption of methyl radicals and the evolution of ethane on the M(111) (M = Co, Ni, Pd, Pt) surfaces, eight metal atoms, in aqueous medium. A maximum of five and four radicals can be adsorbed on Co(111) and Ni...

The ORAC (Oxygen Radical Absorbance Capacity) assay is commonly employed for determining the antioxidant capacity of bioactive peptides. To gain insights into the meaning of this index for peptides containing a single Trp, we studied the consumption...

The reaction of alkenes with hydroxyl (OH) radical is of great importance to atmospheric and combustion chemistry. This work used a combined ab initio/transition state theory (TST) method to study the reaction mechanisms and kinetics for hydrogen abs...

Thiolactones have attracted considerable attention in recent years as bioactive natural products, lead compounds for drug discovery, molecular probes, and reagents for polymerisation. We have investigated radical-mediated C-C bond forming reactions a...

Organic monosubstituted hydrazine derivatives (Ar-NHNH2, RC(O)-NHNH2, Alkyl-NHNH2) are synthetically available, atom-efficient and stable sources of C-centered radicals upon oxidation with extrusion of the energetically favorable N2 molecule. This re...

Two new photopolymerizable vinyl (2-(allyloxy) 1,4-naphthoquinone, HNQA) and epoxy (2-(oxiran-2yl methoxy) 1,4-naphthoquinone, HNQE) photoinitiators derived from lawsone were designed in this paper. These new photoinitiators can be used as one-compon...

The reaction of NH2 radicals with C3H8 is crucial for understanding the combustion behavior of NH3/C3H8 blends. In this study, we investigated the temperature dependence of the rate coefficients for the hydrogen abstraction reactions of C3H8 by NH2 r...

Pleuromutilin is a fungal diterpene natural product with antimicrobial properties, semisynthetic derivatives of which are used in veterinary and human medicine. The development of bacterial resistance to pleuromutilins is known to be very slow, which...

The Kumar model as a molecular model has achieved successful application. However, only 22 reactions limit its veracity and adaptability for feedstocks. A series of models with different degrees of integration of the free radical model and the molecu...