Silver as a powerful electrocatalyst for organic halide reduction: the critical role of molecular structure

Rondinini, Sandra; Mussini, Patrizia R.; Muttini, Paolo; Sello, Guido

doi:10.1016/s0013-4686(01)00616-8

Cited by 157 publications

(115 citation statements)

References 21 publications

Supporting

Mentioning

108

Contrasting

Unclassified

Order By: Relevance

“…As shown in curves b and e, the two reduction peaks shifted to a more positive potential because of the electrocatalytic properties of the Ag electrode. The electrocatalytic activities of electrode materials for the reduction of organic halides have been the subject of many studies [18,19,21,22,[52][53][54]. These studies have shown that Ag exhibits powerful electrocatalytic activities toward the reduction of various organic halides.…”

Section: Introductionmentioning

confidence: 99%

Electrocarboxylation of Dichlorobenzenes on a Silver Electrode in DMF

et al. 2017

View full text Add to dashboard Cite

Carbon dioxide (CO 2 ) is the largest contributor to the greenhouse effect, and fixing and using this greenhouse gas in a facile manner is crucial. This work investigates the electrocarboxylation of dichlorobenzenes with the atmospheric pressure of CO 2 in an undivided cell with an Ag cathode and an Mg sacrificial anode. The corresponding carboxylic acids and their derivatives, which are important industrial and fine chemicals, are obtained. To deeply understand this reaction, we investigate the influence of various reaction conditions, such as supporting electrolyte, current density, electric charge, and reaction temperature, on the electrocarboxylation yield by using 1,4-dichlorobenzene as the model compound. The electrochemical behavior of dichlorobenzenes is studied through cyclic voltammetry. The relation among the distinct electronic effects of dichlorobenzenes, the electrochemical characteristics of their reduction, and the distribution law of target products is also established.

show abstract

Section: Introductionmentioning

confidence: 99%

Electrocarboxylation of Dichlorobenzenes on a Silver Electrode in DMF

et al. 2017

View full text Add to dashboard Cite

show abstract

“…These results nicely demonstrate that the higher-energy excited state reduction potential of PTH is necessary to activate more challenging C-Br bonds (E red = À2.05 to À2.57). 22,23 With a general protocol in place, we next set out to demonstrate the broad applicability of PTH as a photoredox catalyst for a library of aryl iodides and bromides including unactivated, or even deactivated derivatives (Table 2). Excellent activity was observed with compounds containing electron-rich substituents such as 3, 4, and 5 being dehalogenated in high yields.…”

mentioning

confidence: 99%

A highly reducing metal-free photoredox catalyst: design and application in radical dehalogenations

et al. 2015

View full text Add to dashboard Cite

Here we report the use of 10-phenylphenothiazine (PTH) as an inexpensive, highly reducing metal-free photocatalyst for the reduction of carbon-halogen bonds via the trapping of carbon-centered radical intermediates with a mild hydrogen atom donor. Dehalogenations were carried out on various substrates with excellent yields at room temperature in the presence of air.In recent years, photoredox chemistry has enabled the development of a wide variety of synthetic transformations. 1 These methods are based on photocatalysts which, upon absorption of light, enter either a highly reducing or oxidizing excited state capable of facilitating redox-based transformations. In particular, the reduction of activated carbon-halide (C-X) bonds has generated wide interest, largely because of the broad synthetic utility of resulting carbon-centered radical intermediates. [1][2][3][4][5][6][7][8][9][10] One example includes subsequent trapping of these intermediates with a mild H-atom source to achieve radical dehalogenations. 3,5,6,9 In this case, the power of using a photoredox approach is that it offers a more efficient and safer alternative to traditional dehalogenation protocols involving metal-halogen exchange, 11,12 stoichiometric tin hydride, 13 and various other highly toxic reagents. [14][15][16] However, despite the notable advantages of photoredox catalysis, 1 a number of major challenges still exist. This includes the use of catalysts based on rare-earth transition metals such as Ru and Ir, which have inherent limitations due to the cost of the catalyst itself (B$1 mg À1 for Ir(ppy) 3 ), 17 as well as the expense associated with the removal of trace metals from the desired products -critical for applications from pharmaceuticals to micro-electronics. In addition, although an assortment of activated carbon-halogen bonds have been accessed using these catalysts, 1 higher energy unactivated halides are a significantly more challenging task, with only unactivated iodides being explored to date. 5,18 To this end, a more affordable gold-based photocatalyst has been developed, 10 and although offering broader substrate scope, the disadvantages of metal-based systems remain. In addressing this, the use of an organic perylene diimide (PDI)-based photocatalyst was recently reported, and while providing a metal-free alternative, it requires elevated temperatures and has a scope limited to activated aryl-halides. 8 In this context, we envisioned the development of a highly reducing, inexpensive, metal-free photocatalyst that could offer access to a wide range of carbon-halogen substrates under markedly mild conditions (Fig. 1).Our groups previously employed 10-phenylphenothiazine (PTH) as a metal-free catalyst for photomediated atom transfer radical polymerizations (ATRP). 19 In this system, PTH acts as a photoreductant in a similar manner to Ir(ppy) 3 with a reduction potential (E 1/2 * = À2.1 V vs. SCE) significantly higher than Ir(ppy) 3 (E 1/2 * = À1.7 V vs. SCE). Based on our interest in metalfree ATRP, we envisioned that th...

show abstract

“…In this context, the electrochemical dehalogenation of organic halides using nanostructured materials represents a very attractive and feasible alternative for working at mild reaction conditions and reduced costs [26,27]. As it is well documented in the literature, the process efficiency and the main reaction products depend on the electrode material, exhibiting silver the best electrocatalytic activity among all pure metals [9,10,28,29].…”

Section: Page 4 Of 40mentioning

confidence: 99%

“…For this reason, the electrochemical reductive cleavage of carbon-halogen bonds in organic compounds, with the particular focus on volatile organic halides, has been mainly studied and developed in the last decades [10][11][12][13] being the subject of numerous studies in aqueous [14][15][16], non aqueous [17][18][19] and mixed solvents [13,20]. The great interest for this process is due to its important role in some environmental applications, such as the abatement of volatile polychlorinated organic compounds, a group of pollutants having hazardous effects on living beings and out of the scope of most EAOPs.…”

Section: Introductionmentioning

confidence: 99%

Rapid screening of silver nanoparticles for the catalytic degradation of chlorinated pollutants in water

Lugaresi

Perales-Rondón

Minguzzi

et al. 2015

Applied Catalysis B: Environmental

Self Cite

View full text Add to dashboard Cite

Please cite this article as: O. Lugaresi, J.V. Perales-Rondón, A. Minguzzi, J. SollaGullón, S. Rondinini, J.M. Feliu, C.M. Sánchez-Sánchez, Rapid screening of silver nanoparticles for the catalytic degradation of chlorinated pollutants in water, Applied Catalysis B, Environmental (2014), http://dx.doi.org/10. 1016/j.apcatb.2014.08.030 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. We suggest the proper size range and the presence of abundant superficial defective sites, such as steps or kinks, as the main reasons for Ag NPs C1 exhibiting the best overall catalytic performance in trichloromethane electrochemical reduction.

show abstract

Silver as a powerful electrocatalyst for organic halide reduction: the critical role of molecular structure

Cited by 157 publications

References 21 publications

Electrocarboxylation of Dichlorobenzenes on a Silver Electrode in DMF

Electrocarboxylation of Dichlorobenzenes on a Silver Electrode in DMF

A highly reducing metal-free photoredox catalyst: design and application in radical dehalogenations

Rapid screening of silver nanoparticles for the catalytic degradation of chlorinated pollutants in water

Contact Info

Product

Resources

About