1003-73-2Relevant articles and documents
Syntheses of ortho-hydroxymethylpyridinols and dioxaphosphorino[m,n-x]pyridines
Leroy,Despres,Bigan,Blondeau
, p. 2257 - 2272 (1996)
Dioxaphosphorino[m,n-x]pyridines compounds have been prepared by condensation of methyl dichlorophosphate with new ortho-hydroxymethylpyridinols.
Silica-supported vanadium-catalyzed N-oxidation of tertiary amines with aqueous hydrogen peroxide
Rout, Laxmidhar,Punniyamurthy, Tharmalingam
, p. 1958 - 1960 (2005)
A recyclable silica supported vanadium 1 catalyzes the oxidation of tertiray amines to the corresponding N-oxides with 30% H2O 2 in high yield.
Trichloroacetonitrile-hydrogen peroxide: A simple and efficient system for the selective oxidation of tertiary and secondary amines
Nikbakht, Fatemeh,Heydari, Akbar
, p. 2513 - 2516 (2014)
A variety of tertiary and secondary amines were efficiently oxidized to their corresponding N-oxides and nitrones, respectively, using the trichloroacetonitrile-hydrogen peroxide system. The in situ generated trichloromethylperoxyimidic acid is the active reagent for the oxidation processes.
A comparison of methods for N-oxidation of some 3-substituted pyridines
Bremner, David H.,Sturrock, Keith R.,Wishart, Grant,Mitchell, Stewart R.,Nicoll, Stuart M.,Jones, Gareth
, p. 1535 - 1542 (1997)
The results from the N-oxidation of four 3-substituted pyridines using five different reagents are reported. The best yields are obtained with m-chloroperoxybenzoic acid.
Raman spectra of 3-methyl-4-nitropyridine-N-oxide single crystal
Zhang, Delong,Lan, Guoxiang,Hu, Shifen,Wang, Huafu,Zheng, Jimin
, p. 1065 - 1072 (1994)
A Raman study of 3-methyl-4-nitropyridine-N-oxide single crystal (3M4NPO) has been performed at 78 K in the range 10-3500 cm-1.The symmetry analysis of the vibrational modes of 3M4NPO is given.The assignments are presented for internal and external modes.The results of the Raman spectra exhibit the spectroscopic proofs of hydrogen bonds in the crystal.
Organic salts of polyoxometalates: Novel and efficient catalysts for the synthesis of pyridine n-oxide derivatives
Tavakoli-Hoseini, Niloofar,Bamoharram, Fatemeh F.,Heravi, Majid M.
, p. 912 - 915 (2010)
Catalytic N-oxidation of pyridine derivatives to related N-oxides were performed in the peresence of three organic salts of polyoxometalates including two heteropolyanion (THA)7.7H6.3[NaP5W 30O110], 1, and (THPA)7.5 H 6.5[NaP5W30O110], 2, and one isopolyanion [TBA]2[W6O19] (3) with W as central metal atom. Catalyst (3) showed the best catalytic activity. The highly selective oxidation gave good to excellent yields of the related N-oxides along with decarboxylation at 2-position of pyridine ring. The effect of some operative variables, such as temperature, various solvents, and the reaction time was studied. The reaction conditions were optimized. Copyright Taylor & Francis Group, LLC.
Metal-Free, Phosphonium Salt-Mediated Sulfoximination of Azine N-Oxides: Approach for the Synthesis of N-Azine Sulfoximines
Aithagani, Sravan Kumar,Kumar, Mukesh,Yadav, Mahipal,Vishwakarma, Ram A.,Singh, Parvinder Pal
, p. 5886 - 5894 (2016)
Herein, we report a simple and metal-free method for the synthesis of N-azine sulfoximines by the nucleophilic substitution of azine N-oxides with NH-sulfoximines. The present method works at room temperature with wide functional group compatibility and gives several unprecedented N-azine sulfoximines. The reaction conditions were also found suitable with enantiopure substrates and furnished products without any racemization. It also finds an application in the sulfoximination of azine-based functional molecules such as 2,2′-bipyridine, 1,10-phenanthroline, and quinine.
Uniting Amide Synthesis and Activation by PIII/PV-Catalyzed Serial Condensation: Three-Component Assembly of 2-Amidopyridines
Lipshultz, Jeffrey M.,Radosevich, Alexander T.
supporting information, p. 14487 - 14494 (2021/09/18)
An organophosphorus (PIII/PVredox) catalyzed method for the three-component condensation of amines, carboxylic acids, and pyridineN-oxides to generate 2-amidopyridines via serial dehydration is reported. Whereas amide synthesis and functionalization usually occur under divergent reaction conditions, here a phosphetane catalyst (together with a mild bromenium oxidant and terminal hydrosilane reductant) is shown to drive both steps chemoselectively in an auto-tandem catalytic cascade. The ability to both prepare and functionalize amides under the action of a single organocatalytic reactive intermediate enables new possibilities for the efficient and modular preparation of medicinal targets.
Visible-Light-Induced Decarboxylative Acylation of Pyridine N-Oxides with α-Oxocarboxylic Acids Using Fluorescein Dimethylammonium as a Photocatalyst
Hou, Chuanfu,Sun, Shouneng,Liu, Ziqi,Zhang, Hui,Liu, Yue,An, Qi,Zhao, Jian,Ma, Junjie,Sun, Zhizhong,Chu, Wenyi
supporting information, p. 2806 - 2812 (2021/04/15)
Herein, the development of a visible-light-induced catalytic system to achieve the decarboxylative acylation of pyridine N-oxides with α-oxocarboxylic acids, at room temperature and using the organic dye fluorescein dimethylammonium as a new type of photocatalyst, is reported. A series of 2-arylacylpyridine N-oxides were selectively synthesized in moderate to good yields by controlling the polarity of the reaction solvent. The developed strategy was successfully applied in the synthesis of an important intermediate of the drug, acrivastine, on a gram scale. Notably, this is the first time that fluorescein dimethylammonium has been used to catalyze the Minisci-type C?H decarboxylative acylation reaction. The mechanism of decarboxylative acylation was studied by capturing adducts of acyl radicals and 1,1-diphenylethylene to confirm a radical mechanism. The disclosed catalytic system provides a green synthetic strategy for decarboxylative acylation without the use of additional oxidants or metal catalysts. (Figure presented.).
The M?CPbA?NH3(G) system: A safe and scalable alternative for the manufacture of (substituted) pyridine and quinoline N?oxides?
Palav, Amey,Misal, Balu,Ernolla, Anilkumar,Parab, Vinod,Waske, Prashant,Khandekar, Dileep,Chaudhary, Vinay,Chaturbhuj, Ganesh
supporting information, p. 244 - 251 (2019/03/17)
An improved, safe, and scalable isolation process for (substituted) pyridine and quinoline N-oxides in quantitative yields along with high purities using the m-CPBA?NH3(g) system is described. The safety was assessed by reaction calorimetry and differential scanning calorimetry studies for possible hazards during the conversion and isolation steps. Careful interpretation of the data substantiated the safety and scalability. The process flow is simplified to meet the industrial requirements of safety, cost-effectiveness, and utility minimization. The reaction was safely demonstrated at a 2.5 kg scale.
