Xn:Harmful;
98-86-2Relevant articles and documents
Magnetic d-penicillamine-functionalized cellulose as a new heterogeneous support for cobalt(II) in green oxidation of ethylbenzene to acetophenone
Keshipour, Sajjad,Adak, Kamran
, (2017)
A new efficient heterogeneous catalyst is introduced for the oxidation of ethylbenzene. The catalyst was obtained in three steps: functionalization of cellulose with d-penicillamine, deposition of Fe3O4 nanoparticles on cellulose–d-p
Sodium percarbonate: A mild reagent for conversion of tosylhydrazones and nitroalkanes to carbonyl compounds
Narayana,Reddy,Kabalka
, p. 2587 - 2592 (1992)
Sodium percarbonate has been found to be a good reagent for oxidative regeneration of carbonyl compounds from tosyl hydrazones and nitroalkanes.
Debromination of α-Bromo Ketones using Polymer-supported Triphenylphosphine
Dhuru, Sameer P.,Padiya, Kamlesh J.,Salunkhe, M. M.
, p. 56 (1998)
An effective method for the debromination of α-bromo ketones using polymer-supported triphenylphosphine is described.
Atomically dispersed cobalt on graphitic carbon nitride as a robust catalyst for selective oxidation of ethylbenzene by peroxymonosulfate
Li, Jiaquan,Zhao, Shiyong,Yang, Shi-Ze,Wang, Shaobin,Sun, Hongqi,Jiang, San Ping,Johannessen, Bernt,Liu, Shaomin
, p. 3029 - 3035 (2021)
The development of a highly efficient strategy for the activation of the C-H bond in hydrocarbons is one of the most challenging tasks facing the chemical industries. The synthesis of novel catalysts with atomically dispersed active centers is highly desi
Vinyl Triflimides—A Case of Assisted Vinyl Cation Formation
Schroeder, Sebastian,Strauch, Christina,Gaelings, Niklas,Niggemann, Meike
, p. 5119 - 5123 (2019)
A new concept for selectivity control in carbocation-driven reactions has been identified which allows for the chemo-, regio-, and stereoselective addition of nucleophiles to alkynes—assisted vinyl cation formation—enabled by a Li+-based supramolecular framework. Mechanistic analysis of a model complex (Li2NTf2+?3 H2O) confirms that solely the formation of a complex between the incoming nucleophile and the transition state of the alkyne protonation is responsible for the resulting selective N addition to the vinyl cation. Into the bargain, a general, operationally simple synthetic procedure to previously inaccessible vinyl triflimides is provided.
SUBSTITUENT EFFECTS ON THE GAS PHASE BASICITIES OF METHYL BENZOATES. EFFECTS OF RESONANCE DEMAND ON SUBSTITUENT EFFECTS
Mishima, Masaaki,Fujio, Mizue,Tsuno, Yuho
, p. 951 - 954 (1986)
The gas phase basicities of m,p-substituted methyl benzoates have been determined by means of the pulsed ICR mass spectrometer.LArSR analysis of the substituent effect provides a smaller r+ of 0.45 compared to that of acetophenone basicities, indicating a reduced resonance demand of the conjugate acid ion of methyl benzoate.
Origin of enantioselection in chiral alcohol oxidation catalyzed by Pd[(-)-sparteine]Cl2
Mueller, Jaime A.,Cowell, Anne,Chandler, Bert D.,Sigman, Matthew S.
, p. 14817 - 14824 (2005)
A kinetic investigation into the origin of enantioselectivity for the Pd[(-)-sparteine]Cl2-catalyzed aerobic oxidative kinetic resolution (OKR) is reported. A mechanism to account for a newly discovered chloride dissociation from Pd[(-)-sparteine]Cl2 prior to alcohol binding is proposed. The mechanism includes (1) chloride dissociation from Pd[(-)-sparteine]Cl2 to form cationic Pd(-)-sparteine]Cl, (2) alcohol binding, (3) deprotonation of Pd-bound alcohol to form a Pd-alkoxide, and (4) β-hydride elimination of Pd-alkoxide to form ketone product and a Pd-hydride. Utilizing the addition of (-)-sparteine HCl to control the [Cl -] and [H+] and the resulting derived rate law, the key microscopic kinetic and thermodynamic constants were extracted for each enantiomer of sec-phenethyl alcohol. These constants allow for the successful simulation of the oxidation rate in the presence of exogenous (-)-sparteine HCl. A rate law for oxidation of the racemic alcohol was derived that allows for the successful prediction of the experimentally measured krel values when using the extracted constants. Besides a factor of 10 difference between the relative rates of β-hydride elimination for the enantiomers, the main enhancement in enantiodetermination results from a concentration effect of (-)-sparteine HCl and the relative rates of reprotonation of the diastereomeric Pd-alkoxides.
Photoredox Catalysis Using Heterogenized Iridium Complexes**
Materna, Kelly L.,Hammarstr?m, Leif
, p. 16966 - 16977 (2021)
Heterogenized photoredox catalysts provide a path for sustainable chemical synthesis using highly tunable, reusable constructs. Here, heterogenized iridium complexes as photoredox catalysts were assembled via covalent attachment to metal oxide surfaces (I
Influence of induced steric on the switchover reactivity of mononuclear Cu(II)-alkylperoxo complexes
Nag, Sayanta Sekhar,Mukherjee, Gourab,Barman, Prasenjit,Sastri, Chivukula V.
, p. 80 - 85 (2019)
Coordination and steric environment around a metal center plays an indispensable role in its reactivity. In this report we have synthesized two bispidine based Cu(II)-OOR (R = tBu) complexes [Cu(L1)(OOtBu)]+ and [Cu(L2)(OOtBu)]+ having different steric environment around the metal center and characterized by various spectroscopic techniques. These Cu(II)-OOR species show reactivity towards oxygen atom transfer and aldehyde deformylation reactions. In contrast to the previously reported nucleophilic oxidation, aldehyde deformylation reaction by these complexes proceed via an initial H-atom abstraction with KIE of 12 and 8 respectively. It has been observed that more steric bulk at N3 and N7 position of bispidine ligand prefers the oxygen atom transfer reaction while it hinders the H-atom abstraction for Cu(II)-alkylperoxo complexes.
Synthesis of new hybrid hydroquinone/cobalt schiff base catalysts: Efficient electron-transfer mediators in aerobic oxidation
Purse, Byron W.,Tran, Lien-Hoa,Piera, Julio,Akermark, Bjoern,Baeckvall, Jan-Erling
, p. 7500 - 7503 (2008)
A study was conducted to demonstrate the use of efficient electron-transfer mediators in aerobic oxidation. These electron-transfer mediators were used in aerobic oxidation for synthesizing new hybrid hydroquinone and Cobalt Schiff base catalysts. These n
