ChemInform Abstract: C3-Symmetric Titanium(IV) Triphenolate Amino Complexes for a Fast and Effective Oxidation of Secondary Amines to Nitrones with Hydrogen Peroxide.

ChemInform ◽  
2009 ◽  
Vol 40 (11) ◽  
Author(s):  
Cristiano Zonta ◽  
Elisa Cazzola ◽  
Miriam Mba ◽  
Giulia Licini
Keyword(s):  
Hydrogen Peroxide ◽  
Secondary Amines ◽  
Amino Complexes

scholarly journals Kinetic resolution of indolines by asymmetric hydroxylamine formation

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Gang Wang ◽  
Ran Lu ◽  
Chuangchuang He ◽  
Lei Liu
Keyword(s):  
Hydrogen Peroxide ◽  
Chemical Synthesis ◽  
Late Stage ◽  
Kinetic Resolution ◽  
High Efficiency ◽  
Bond Formation ◽  
Bioactive Molecules ◽  
Environmentally Benign ◽  
Secondary Amines

AbstractCatalytic kinetic resolution of amines represents a longstanding challenge in chemical synthesis. Here, we described a kinetic resolution of secondary amines through oxygenation to produce enantiopure hydroxylamines involving N–O bond formation. The economic and practical titanium-catalyzed asymmetric oxygenation with environmentally benign hydrogen peroxide as oxidant is applicable to a range of racemic indolines with multiple stereocenters and diverse substituent patterns in high efficiency with efficient chemoselectivity and enantio-discrimination. Late-stage asymmetric oxygenation of bioactive molecules that are otherwise difficult to synthesize was also explored.

Methyltrioxorhenium-catalysed oxidation of secondary amines to nitrones in ionic liquids

2013 ◽  
Vol 67 (1) ◽  
Author(s):  
Mária Mečiarová ◽  
Melinda Mojzesová ◽  
Radovan Šebesta
Keyword(s):  
Hydrogen Peroxide ◽  
Ionic Liquids ◽  
Ultrasonic Irradiation ◽  
Catalytic Amount ◽  
Positive Influence ◽  
Secondary Amines ◽  
Catalysed Oxidation ◽  
Reaction Cycles

AbstractNitrones serve as starting materials for the synthesis of many heterocycles. Oxidation of secondary amines using hydrogen peroxide and the catalytic amount of methyltrioxorhenium in ionic liquids is a useful method for the preparation of nitrones. Ultrasonic irradiation and ionic liquids have a positive influence on the reaction. The nitrones required were isolated in good yields. Corresponding hydroxylamines, which can be easily oxidised to nitrones, often accompanied the main products. Methyltrioxorhenium in ionic liquids was re-used in several reaction cycles without any deteriorating effect on the course of the reaction.

Chemical Attack of Graphite/Epoxy by Hydrogen Peroxide

1992 ◽  
Vol 46 (3) ◽  
pp. 524-528 ◽  
Author(s):  
Forrest E. Sloan
Keyword(s):  
Hydrogen Peroxide ◽  
Broad Band ◽  
Secondary Amines ◽  
Ir Radiation ◽  
Chemical Corrosion ◽  
High Ph ◽  
Reinforced Plastics ◽  
Chemical Attack ◽  
Graphite Fibers ◽  
Ft Ir

Techniques for studying the mechanisms of chemical corrosion in fiber-reinforced plastics are of considerable importance. The most common analysis technique for studying chemical changes in polymers is Fourier transform infrared (FT-IR) spectroscopy. For polymers reinforced with graphite fibers, however, study of the matrix is hindered by the presence of the graphite, which strongly absorbs IR radiation in a broad band of wavelengths. The purpose of this study was to investigate the degradation of AS-4/3501-5a graphite/epoxy composite material exposed to solutions of hydrogen peroxide. Evidence was also sought for degradation in high pH (up to pH = 12) solutions. After long-term environmental exposure, a simple gravity flotation technique was used to separate the epoxy matrix from the graphite fibers for FT-IR analysis. The resulting spectroscopic evidence indicates that hydrogen peroxide attacks the secondary amines in the cured epoxy structure. No evidence of attack by high pH solutions was found.

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