578-58-5Relevant articles and documents
Solvolysis of o-methylbenzenediazonium tetrafluoroborate in acidic methanol-water mixtures. Further evidence for nucleophilic attack on a solvent separated aryl cation
Pazo-Llorente,Sarabia-Rodriguez,Gonzalez-Romero,Bravo-Diaz
, p. 531 - 538 (1999)
Rate constants for dediazoniation product formation and arenediazonium ion loss and product yields of solvolysis of o-methylbenzenediazonium tetrafluoroborate in acidic methanol-water mixtures at T = 35 °C are reported. Observed rate constants for diazonium ion loss and product formation are the same, increasing about 45% ongoing from water to methanol, and are not affected by added electrolytes like HCl, NaCl, and CuCl2. Only three dediazoniation products are detected, o-cresol, o-chlorotoluene, and o-anisole. All data are consistent with a rate-determining step formation of an aryl cation that reacts immediately with available nucleophiles. The selectivity of the reaction toward nucleophiles, S, which can be is low and essentially constant upon changing solvent composition, suggesting that the nucleophilic attack takes place on a solvent separated aryl cation.
Impact of oxygen vacancies in Ni supported mixed oxide catalysts on anisole hydrodeoxygenation
Ali, Hadi,Kansal, Sushil Kumar,Lauwaert, Jeroen,Saravanamurugan, Shunmugavel,Thybaut, Joris W.,Vandevyvere, Tom
, (2022/03/02)
The hydrodeoxygenation (HDO) activity of anisole has been investigated over Ni catalysts on mixed metal oxide supports containing Nb–Zr and Ti–Zr in 1:1 and 1:4 ratios. XRD patterns indicate the incorporation of Ti (or Nb) into the ZrO2 framewo
Optimizing the carburization conditions of supported rhenium carbide for guaiacol conversion
Blanco, Elodie,Dongil, Ana Belén,Escalona, Néstor,García-Fierro, Jose Luis,Ghampson, I. Tyrone
, (2021/06/26)
The present work evaluates the effect of ethylene content of a carburization mixture on the formation of carburized rhenium supported on activated carbon. The resulting catalysts were characterized by N2 physisorption, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy and temperature-programmed reduction, and the results show a strong effect on the final phase obtained. A high amount of ethylene inhibited the carburization process, resulting in carbon formation, while a lower amount (≤ 35 %) of ethylene was favorable to the formation of the carbide phase. The catalysts were evaluated for the hydrodeoxygenation (HDO) of guaiacol, a bio-oil model compound, and a high yield of benzene (50 %), a desirable aromatic compound, was obtained at complete conversion over the catalysts containing the carbide phase.
Trialkylammonium salt degradation: Implications for methylation and cross-coupling
Assante, Michele,Baillie, Sharon E.,Juba, Vanessa,Leach, Andrew G.,McKinney, David,Reid, Marc,Washington, Jack B.,Yan, Chunhui
, p. 6949 - 6963 (2021/06/02)
Trialkylammonium (most notably N,N,N-trimethylanilinium) salts are known to display dual reactivity through both the aryl group and the N-methyl groups. These salts have thus been widely applied in cross-coupling, aryl etherification, fluorine radiolabelling, phase-transfer catalysis, supramolecular recognition, polymer design, and (more recently) methylation. However, their application as electrophilic methylating reagents remains somewhat underexplored, and an understanding of their arylation versus methylation reactivities is lacking. This study presents a mechanistic degradation analysis of N,N,N-trimethylanilinium salts and highlights the implications for synthetic applications of this important class of salts. Kinetic degradation studies, in both solid and solution phases, have delivered insights into the physical and chemical parameters affecting anilinium salt stability. 1H NMR kinetic analysis of salt degradation has evidenced thermal degradation to methyl iodide and the parent aniline, consistent with a closed-shell SN2-centred degradative pathway, and methyl iodide being the key reactive species in applied methylation procedures. Furthermore, the effect of halide and non-nucleophilic counterions on salt degradation has been investigated, along with deuterium isotope and solvent effects. New mechanistic insights have enabled the investigation of the use of trimethylanilinium salts in O-methylation and in improved cross-coupling strategies. Finally, detailed computational studies have helped highlight limitations in the current state-of-the-art of solvation modelling of reaction in which the bulk medium undergoes experimentally observable changes over the reaction timecourse. This journal is