Selective and one-pot formation of phenols by anodic oxidation

Fujimoto, K.; Tokuda, Yuichiro; Maekawa, Hirofumi; Matsubara, Yoshiharu; Mizuno, Takumi; Nishiguchi, Ikuzo

doi:10.1016/s0040-4020(96)00056-7

Cited by 50 publications

(26 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Perchlorates were purchased from Aldrich. All the obtained esters were characterized by 1 H and 13 C NMR spectroscopy and the data were compared to those of authentic compounds, both commercially available ( 1b , 3b , 4b , 6b , 8b , 9b , 13b , 15b , 16b , 17b , 20b , 24b , 1c , 2c , 17c ) or previously reported ( 2b ,23 5b ,24 7b ,24 10b ,25 14b ,26 18b ,27 19b ,28 22b ,29 1d ,30 1e ,31 1f ,31 1g ,31 5c 32). 1 H NMR experiments were recorded at 300 MHz with a Varian Gemini instrument.…”

Section: Methodsmentioning

confidence: 99%

In the Twilight Zone between [2]Pseudorotaxanes and [2]Rotaxanes

Jeppesen

Vignon

Stoddart

2003

Chemistry A European J

View full text Add to dashboard Cite

A [2]pseudorotaxane, based on a semi-dumbbell-shaped component containing asymmetrically substituted monopyrrolotetrathiafulvalene and 1,5-dioxynaphthalene recognition sites for encirclement by cyclobis(paraquat-p-phenylene) and with a "speed bump" in the form of a thiomethyl group situated between the two recognition sites, has been self-assembled. This supramolecular entity is a mixture in solution of two slowly interconverting [2]pseudorotaxanes, one of which is on the verge of being a [2]rotaxane at room temperature, allowing it to be isolated by employing flash column chromatography. These two [2]pseudorotaxanes were both characterized in solution by UV/Vis and (1)H NMR spectroscopies (1D and 2D) and also by differential pulse voltammetry. The spectroscopic and electrochemical data reveal that one of the complexes behaves wholly as a [2]pseudorotaxane, while the other has some [2]rotaxane character to it. The kinetics of the shuttling of cyclobis(paraquat-p-phenylene) between the monopyrrolotetrathiafulvalene and the 1,5-dioxynaphthalene recognition sites have been investigated at different temperatures. The shuttling processes, which are accompanied by detectable color changes, can be monitored using UV/Vis and (1)H NMR spectroscopies; the spectroscopic data have been employed in the determination of the rate constants, free energies of activation, enthalpies of activation, and the entropies of activation for the translation of cyclobis(paraquat-p-phenylene) between the two recognition sites.

show abstract

Section: Methodsmentioning

confidence: 99%

In the Twilight Zone between [2]Pseudorotaxanes and [2]Rotaxanes

Jeppesen

Vignon

Stoddart

2003

Chemistry A European J

View full text Add to dashboard Cite

show abstract

“…[37,[64][65][66][67][68] In addition, the oxidation potential of anisole is also lowered in a protic environment. [63,69] These cooperative redox-potential shifts strongly favor the ET step thermodynamically. As discussed above, specific solvation of the triplet excited BP also became evident during this study.…”

Section: Mechanistic Implicationsmentioning

confidence: 99%

Efficient Photochemical Oxidation of Anisole in Protic Solvents: Electron Transfer driven by Specific Solvent–Solute Interactions

et al. 2010

View full text Add to dashboard Cite

The dynamics of the bimolecular quenching of triplet excited benzophenone by anisole was studied by nanosecond flash photolysis. We carried out a detailed study of the solvent dependence of the reaction rates and efficiencies in a number of protic and non-protic solvents. These studies were augmented by theoretical modelling and experimental investigation of solute/solvent interactions in the triplet excited and the ground state, respectively. The triplet quenching that follows Stern-Volmer kinetics in all cases is profoundly dependent on the nature of the solvent, with the highest reactivity being consistently found in protic solvents. The results in non-protic solvents are compatible with unproductive quenching via a charge-transfer state, whereas the generally fast quenching in protic solvents is accompanied by efficient formation of free-radical products. Analysis of the solvent dependence in terms of Marcus theory reveals the impact of specific solvation of benzophenone by protic solvents on the ET driving force and kinetics. Specific solvation is found to support efficient free radical ion formation in media of moderate and low polarity as well.

show abstract

“…However, another possible pathway is the oxidation of benzene to produce a benzene radical cation that could react with a water molecule to form phenol. [24,25] No new band was observed when the cathodic current was applied (Figure 3 d), which indicates that the cathodically activated oxygen species is qualitatively distinct from the anodically activated oxygen species, and this is supported by the difference in the catalytic properties of the two active oxygen species (Figure 1 b and Figure 2 b). Identification of the cathodically activated oxygen species still remains unclear at the present time.…”

mentioning

confidence: 90%