123-75-1Relevant articles and documents
Photo-oxidation of L-Tyrosine, an Efficient 1,4-Chirality Transfer Reaction
Endo, Katsuya,Seya, Kazuhiko,Hikino, Hiroshi
, p. 934 - 935 (1988)
Dye-sensitized oxidation of L-tyrosine with Rose Bengal yielded the optically pure ketolactam (2) stereoselectively in one step.
SALT EFFECTS ON THE KINETICS OF SUBSTITUTION OF THE PENTACYANO(PYRROLIDINE)FERRATE(II) ION
Pedrosa, Graciela C.,Hernandez, Norma L.,Katz, Nestor E.,Katz, Miguel
, p. 2297 - 2299 (1980)
Rate constants at 298.2 K for the release of pyrrolidine from pentacyano(pyrrolidine)ferrate(II) have been measured under pseudo-first-order conditions and the effect of inert inorganic and alkylammonium salts on the kinetics were investigated.The observe
Mechanistic Investigations of the Catalytic Formation of Lactams from Amines and Water with Liberation of H2
Gellrich, Urs,Khusnutdinova, Julia R.,Leitus, Gregory M.,Milstein, David
, p. 4851 - 4859 (2015)
The mechanism of the unique lactam formation from amines and water with concomitant H2 liberation with no added oxidant, catalyzed by a well-defined acridine-based ruthenium pincer complex was investigated in detail by both experiment and DFT calculations. The results show that a dearomatized form of the initial complex is the active catalyst. Furthermore, reversible imine formation was shown to be part of the catalytic cycle. Water is not only the oxygen atom source but also acts as a cocatalyst for the H2 liberation, enabled by conformational flexibility of the acridine-based pincer ligand. (Figure Presented).
Ion Confinement in the Collision Cell of a Multiquadrupole Mass Spectrometer: Access to Chemical Equilibrium and Determination of Kinetic and Thermodynamic Parameters of an Ion-Molecule Reaction
Beaugrand, Claude,Jaouen, Daniel,Mestdagh, Helene,Rolando, Christian
, p. 1447 - 1453 (1989)
Ions can be confined in an rf-only collision cell of a tandem quadrupole mass spectrometer so that ion-molecule reactions can be studied for variable interaction times (0.05-250 ms).The chemical system studied (ammonium ion, pyrrolidine, piperidine) involved the following reactions: proton exchange, formation of proton-bound dimers, and amine exchange between dimers.Chemical equilibrium could be reached for the exchange reactions.The equilibrium constants of these reactions, as well as the rate constants of the different reactions involved, were thus easily determined from the variation of relative abundance of reactant and product ions versus confinement time.
PHOTOSENSITIZED SINGLE ELECTRON TRANSFER INITIATED N-DEBENZYLATION. A CONVENIENT AND MILD APPROACH
Pandey, G.,Rani, K. Sudha
, p. 4157 - 4158 (1988)
A mild method of N-debenzylation via photosensitized single electron transfer (SET) using 9,10-dicyano anthracene (DCA) as electron acceptor in neutral medium is reported.
Novel β-galactosidase-specific O2-glycosylated diazeniumdiolate probes
Bedell, Barry,Bohle,Chua, Zhijie,Czerniewski, Alexander,Evans, Alan,Mzengeza, Shadreck
, p. 969 - 980 (2010)
Three β-galactosidase-specific nitric-oxide-releasing diazeniumdiolate conjugated probes were prepared as a prelude to studies of new potential molecular MRI imaging agents. A glycosylated derivative, 2e, designed to be trafficked across cell membranes, was also prepared. We report, in detail, the synthesis and characterization of these probes. In addition, the release of diazeniumdiolate from the probes by β-galactosidase-catalyzed hydrolysis was used to estimate their efficacy as serum-stable, specific NO donors.
Surface ligands enhance the catalytic activity of supported Au nanoparticles for the aerobic α-oxidation of amines to amides
Chatterjee, Puranjan,Kanbur, Uddhav,Manzano, J. Sebastián,Sadow, Aaron D.,Slowing, Igor I.,Wang, Hsin
, p. 1922 - 1933 (2022/04/07)
The catalytic aerobic α-oxidation of amines in water is an atom economic and green alternative to current methods of amide synthesis. The reaction uses O2 as terminal oxidant, avoids hazardous reactants and gives water as the only byproduct. Here we report that the catalytic activity of silica-supported Au nanoparticles for the aerobic α-oxidation of amines can be improved by tethering pyridyl ligands to the support. In contrast, immobilization of thiol groups on the material gives activities comparable to Au supported on bare silica. Our studies indicate that the ligands affect the electronic properties of the Au nanoparticles and thereby determine their ability to activate O2 and mediate C-H cleavage in the amine substrate. The reaction likely proceeds via an Au catalyzed β-hydride elimination enabled by backdonation from electron-rich metal to the orbital. O2, which is also activated on electron-rich Au, acts as a scavenger to remove H from the metal surface and regenerate the active sites. The mechanistic understanding of the catalytic conversion led to a new approach for forming C-C bonds α to the N atoms of amines.
A Lewis Base Nucleofugality Parameter, NFB, and Its Application in an Analysis of MIDA-Boronate Hydrolysis Kinetics
García-Domínguez, Andrés,Gonzalez, Jorge A.,Leach, Andrew G.,Lloyd-Jones, Guy C.,Nichol, Gary S.,Taylor, Nicholas P.
supporting information, (2022/01/04)
The kinetics of quinuclidine displacement of BH3 from a wide range of Lewis base borane adducts have been measured. Parameterization of these rates has enabled the development of a nucleofugality scale (NFB), shown to quantify and predict the leaving group ability of a range of other Lewis bases. Additivity observed across a number of series R′3-nRnX (X = P, N; R′ = aryl, alkyl) has allowed the formulation of related substituent parameters (nfPB, nfAB), providing a means of calculating NFB values for a range of Lewis bases that extends far beyond those experimentally derived. The utility of the nucleofugality parameter is explored by the correlation of the substituent parameter nfPB with the hydrolyses rates of a series of alkyl and aryl MIDA boronates under neutral conditions. This has allowed the identification of MIDA boronates with heteroatoms proximal to the reacting center, showing unusual kinetic lability or stability to hydrolysis.
Method for protecting sulfonyl of deamination amine
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Paragraph 0054-0056, (2021/11/03)
The invention discloses a method for removing sulfenyl protection of amine. The method comprises the following steps: dissolving N - sulfonyl-protected amine and a base in a reaction solvent, then adding diphenylphosphine to uniformly mix and maintain 90 °C. When TCL detection reaction is complete, a recrystallization method or an extraction separation method is adopted to obtain the target product. The method disclosed by the invention adopts diphenylphosphine as an extraction reagent, is good in reaction activity, high in selectivity and wide in application range, and can replace the use of a hazardous reagent under the basic heating condition. Prodrug research and development and industrial production are of great significance.
Zirconium-hydride-catalyzed site-selective hydroboration of amides for the synthesis of amines: Mechanism, scope, and application
Han, Bo,Jiao, Haijun,Wu, Lipeng,Zhang, Jiong
, p. 2059 - 2067 (2021/09/02)
Developing mild and efficient catalytic methods for the selective synthesis of amines is a longstanding research objective. In this respect, catalytic deoxygenative amide reduction has proven to be promising but challenging, as this approach necessitates selective C–O bond cleavage. Herein, we report the selective hydroboration of primary, secondary, and tertiary amides at room temperature catalyzed by an earth-abundant-metal catalyst, Zr-H, for accessing diverse amines. Various readily reducible functional groups, such as esters, alkynes, and alkenes, were well tolerated. Furthermore, the methodology was extended to the synthesis of bio- and drug-derived amines. Detailed mechanistic studies revealed a reaction pathway entailing aldehyde and amido complex formation via an unusual C–N bond cleavage-reformation process, followed by C–O bond cleavage.
