6277-35-6Relevant articles and documents
Improvement in efficiency of the electrocatalytic reduction of hydrogen peroxide by prussian blue produced from the [fe(CN)5(mpz)]2-complex
Monteiro, Marcio C.,Toledo, Kalil C. F.,Pires, Bruno M.,Wick, René,Bonacin, Juliano A
, p. 1979 - 1988 (2017)
Hydrogen peroxide is one of the most important molecules in chemical signaling in living organisms. Because of this, its sensing is indispensable for the diagnosis of many diseases. Among the materials used for the detection and quantification of H2O2, Prussian Blue (Phas been highlighted due to its performance. Therefore, the search for alternatives or the improvement of PB performance is a challenge. In this context, our motivation was to evaluate how the ligand N-methylpyrazinium affects the structure and reactivity of Prussian Blue films produced from [Fe(CN)5(mpz)]2-(PB-mpz). Based on the results, it was possible to conclude that the ligand is coordinated to the complex inside the PB framework and consequently contributes to the generation of a noncrystalline structure. The ions contained in buffer solutions can react with Prussian Blue by binding to Fe3+ and breaking the structure. In addition, a PBmpz film in HCl/KCl showed higher sensitivity towards H2O2 than a PB film.
Identification of N- or O-Alkylation of Aromatic Nitrogen Heterocycles and N-Oxides Using 1H–15N HMBC NMR Spectroscopy
Bateman, Lorraine M.,Breugst, Martin,Byrne, Peter A.,Flosbach, Niko T.,Sheehy, Kevin J.
supporting information, (2020/06/02)
A series of representative diazines and pyridine N-oxides were subjected to alkylation using several different alkylating agents. The 15N NMR chemical shifts (δN values) of the diazines, pyridine N-oxides and derived alkylation products were determined using 1H-15N HMBC NMR spectroscopy at natural 15N abundance. The changes in the 15N NMR chemical shifts (Δ(δN) values) that occurred on going from starting materials to products in these reactions were analyzed. N-alkylation of diazines resulted in large upfield shifts of the δN values of the alkylated nitrogen (of the order of 100 ppm or greater). While O-alkylation of pyridine N-oxides resulted in upfield shifts of the δN values of the N-(alkoxy)pyridinium nitrogen, the Δ(δN) values were of a much smaller magnitude (ca. –42 ppm) than those observed for N-alkylations of diazines. Nitrogen NMR spectroscopic data from the literature of relevance to alkylation of azines, diazines, azine N-oxides and diazine N-oxides was gathered together, and using this in tandem with our 15N NMR spectroscopic data, we have been able to corroborate our observations on the trends observed in the Δ(δN) values associated with N- and O-alkylation reactions of aromatic N-heterocycles and N-oxides. An analysis protocol that relies on synergistic evaluation of 1H-15N HMBC and 1H-13C HMBC NMR spectra has been developed that enables unambiguous diagnosis of the occurrence of N-alkylation of aromatic N-heterocycles and O-alkylation of aromatic N-oxides.
PREPARATION AND STRUCTURE ELUCIDATION OF SOME N-ALKYLPYRAZINIUM SALTS AND THEIR N-OXIDES
Jovanovic, Misa V.
, p. 2299 - 2315 (2007/10/02)
Several N4-alkylpyrazinium N-oxide salts were prepared in high yields by heating the corresponding pyrazine N1-oxides in the presence of alkylating reagent and solvent.The proton nmr data point to the quinoidal nature of these compounds.Pyrazine di-N-oxides deoxygenated rapidly under same reaction conditions to yield a mixture of N-alkylpyrazinium and N-alkylpyrazinium mono-N-oxide salts.Mechanism is proposed to account for these reductive deoxygenations of the pyrazine nucleus.
