113123-23-2Relevant academic research and scientific papers
SELENIUM DIOXIDE CATALYZED OXIDATION OF SECONDARY AMINES WITH HYDROGEN PEROXIDE. SIMPLE SYNTHESIS OF NITRONES FROM SECONDARY AMINES
Murahashi, Shun-Ichi,Shiota, Tatsuki
, p. 2383 - 2386 (1987)
Oxidation of secondary amines with hydrogen peroxide in the presence of selenium dioxide catalyst at room temperature gives nitrones, which are versatile synthetic intermediates, highly efficiently.
Oxidation of secondary amines to nitrones using urea-hydrogen peroxide complex (UHP) and metal catalysts
Marcantoni, Enrico,Petrini, Marino,Polimanti, Olga
, p. 3561 - 3562 (1995)
Secondary amines can be readily oxidized to the corresponding nitrones using urea-hydrogen peroxide complex (UHP) and metal catalysts in methanol at room temperature. Sodium tungstate is the most effective catalyst in several runs and common protecting groups are tolerated in these conditions.
Synthesis of nitrones using the methyltrioxorhenium/hydrogen peroxide system
Murray, Robert W.,Iyanar, Kaliappan,Chen, Jianxin,Wearing, James T.
, p. 8099 - 8102 (1996)
Secondary amines are oxidized by the methyltrioxorhenium/hydrogen peroxide system to the corresponding nitrones in excellent yield. The results provide a further example of the parallel between the chemistry of this metal system and that of the dioxiranes.
Metal-Free Solvent Promoted Oxidation of Benzylic Secondary Amines to Nitrones with H2O2
Adrio, Javier,Amarante, Giovanni Wilson,Granato, álisson Silva
, p. 13817 - 13823 (2021/10/01)
An environmentally benign protocol for the generation of nitrones from benzylic secondary amines via catalyst-free oxidation of secondary amines using H2O2 in MeOH or CH3CN is described. This methodology provides a selective access to a variety of C-aryl nitrones in yields of 60 to 93%. Several studies have been performed to shed light on the reaction mechanism and the role of the solvent.
Organotin-oxotungstate coordination polymer: An efficient catalyst for the selective oxidation of amines
Nikbakht, Fatemeh,Heydari, Akbar
, p. 132 - 136 (2015/03/04)
The organometallic coordination polymer [(nBu3Sn)2WO4] catalyzed the selective oxidation of secondary and primary amines to nitrones and oximes, respectively. The catalyst was found to be reusable for five catalytic cycles without any appreciable loss in activity. Under the optimized reaction conditions [4 mol% catalyst, 3-4 equiv of hydrogen peroxide (30 wt%, aqueous solution), methanol as the solvent, r.t.], the corresponding nitrones and oximes were obtained with good efficiency.
Evasive neutral 2-aza-cope rearrangements. Kinetic and computational studies with cyclic nitrones
Delso, Ignacio,Melicchio, Alessandro,Isasi, Arantzazu,Tejero, Tomas,Merino, Pedro
supporting information, p. 5721 - 5730 (2013/09/12)
A full experimental study of the activation energy required for the hitherto unknown neutral 2-aza-Cope rearrangement is presented. A kinetic study of the process showed activation energies in the range of 22.91-24.06 kcal/mol, in agreement with a process operating at moderate temperature (70°C). Calculations at B3LYP/6-311+G(d,p) and M06-2X/6-311+G(d,p) levels of theory considering solvent (dimethyl sulfoxide (DMSO) and toluene) effects (PCM model) predict reaction energy barriers that are in agreement with the values obtained from 1H NMR-based kinetic experiments. Results obtained by using enantiomerically pure substrates demonstrate that the rearrangement takes place with complete transfer of chirality, in contrast to previously described cationic processes. The effects of solvent and acid catalysis, which converts the process into the more common cationic rearrangement, have also been studied. DFT calculations also predict correctly the acceleration of the process under acid catalysis, estimating energy barriers in the range of 16.80-18.57 kcal/mol. The hitherto unknown neutral 2-aza-Cope rearrangement of nitrones takes place under thermal conditions with complete transfer of chirality. The process can be catalyzed by acid through a classical cationic 2-aza-Cope rearrangement. Kinetic 1H NMR experiments and DFT theoretical studies have been used to estimate the activation parameters and determine the energy of activation of the process. Copyright
Oxidation of secondary amines to nitrones using magnetically separable tungstophosphoric acid supported on silica-encapsulated γ-Fe 2O3 nanoparticles
Nikbakht, Fatemeh,Heydari, Akbar,Saberi, Dariush,Azizi, Kobra
, p. 6520 - 6523 (2013/11/19)
Superparamagnetic tungstophosphoric acid supported on silica-encapsulated γ-Fe2O3 was used as an efficient catalyst for the direct oxidation of secondary amines to nitrones with hydrogen peroxide as the oxidant. The catalyst could be recycled up to four times without significant loss of activity.
Effective oxidation of secondary amines to nitrones with alkyl hydroperoxides catalysed by (Trialkanolaminato)titanium(IV) complexes
Forcato, Massimiliano,Mba, Miriam,Nugent, William A.,Licini, Giulia
experimental part, p. 740 - 748 (2010/03/26)
The effective catalytic oxidation of secondary amines to nitrones with, alkyl hydroperoxides as the primary oxidants is described. The titanium, alkoxi.de catalysts are protected. from the water co-product by the combined use of a tightly binding trialkanolamine ligand and molecular sieves. Nitrones can be obtained in high yields (up to 98%) under homogeneous, anhydrous conditions and even in the absence of solvent. The reactions are fast (2-7 h) and good selectivity and complete conversion can be achieved with as little as 1 % catalyst.
Synthesis of nitrones by methyltrioxorhenium catalyzed direct oxidation of secondary amines
Goti, Andrea,Nannelli, Luca
, p. 6025 - 6028 (2007/10/03)
Oxidation of secondary amines catalyzed by methyltrioxorhenium (MTO) with H2O2 or urea-hydrogen peroxide complex (UHP) at room temperature gives the corresponding nitrones in good yields.
Tungstate-Catalyzed Oxidation of Secondary Amines to Nitrones. α-Substitution of Secondary Amines via Nitrones
Murahashi, Shun-Ichi,Mitsui, Hitoshi,Shiota, Tatsuki,Tsuda, Tomoyasu,Watanabe, Shoji
, p. 1736 - 1744 (2007/10/02)
The sodium tungstate catalyzed oxidation of secondary amines with hydrogen peroxide gives the corresponding nitrones.Acyclic and cyclic nitrones can be obtained from secondary amines in a single step in good to escellent yields.The oxidation of secondary amines in the presence of alkenes gives isoxazolidines by 1,3-dipolar cycloaddition of nitrones.Introduction of a substituent at the α-position of secondary amines can be performed upon oxidation of secondary amines and subsequent treatment with various nucleophiles.
