555-16-8Relevant articles and documents
Kinetics and mechanism of oxidation of chloramphenicol - An antibiotic drug by diperiodatocuprate(III) in aqueous alkaline medium
Hosahalli, Rajeshwari V.,Byadagi, Kirthi S.,Nandibewoor, Sharanappa T.,Chimatadar, Shivamurti A.
, p. 79 - 94 (2011)
The kinetics of oxidation of chloramphenicol (CHP) by diperiodatocuprate(III) (DPC) in aqueous alkaline medium at a constant ionic strength of 0.10 mol dm-3 was studied spectrophotometrically. The reaction between DPC and CHP in alkaline medium exhibits 1:2 stoichiometry (CHP: DPC). The main oxidation products were identified by spot test, IR, NMR and GCMS spectral studies. The reaction is of first order in DPC and CHP concentrations. As the alkali concentration increases the rate of reaction increases with fractional order dependence on alkali concentration. Increase in periodate concentration decreases the rate. A suitable mechanism is proposed. The reaction constants involved in the different steps of the mechanism were calculated. The activation parameters with respect to slow step of the mechanism are computed and discussed. Thermodynamic quantities are also determined. by Oldenbourg Wissenschaftsverlag, Munchen.
Kinetics and mechanism of ruthenium(III) catalyzed oxidation of chloromphenicol - An antibiotic drug by diperiodatocuprate(III) in aqueous alkaline medium
Hosahalli,Byadagi,Nandibewoor,Chimatadar
, p. 65 - 74 (2012)
The kinetics of ruthenium(III) catalyzed oxidation of chloramphenicol (CHP) by diperiodatocuprate(III) (DPC) in aqueous alkaline medium at a constant ionic strength of 0.1 mol l-1 was studied spectrophotometrically. The reaction between DPC and CHP in alkaline medium exhibits 1: 2 stoichiometry (CHP: DPC). The main oxidation products were identified by spot test, IR, NMR, and GC-MS spectral studies. The reaction is first order with respect to ruthenium(III) and DPC concentrations. The order with respect to chloramphenicol concentration varies from first order to zero order as the chloramphenicol concentration increases. As the alkali concentration increases the reaction rate increases with fractional order dependence on alkali concentration. Increase in periodate concentration decreases the rate. A mechanism adequately describing the observed regularities is proposed. The reaction constants involved in the different steps of the mechanism were calculated. The activation parameters with respect to limiting step of the mechanism are computed and discussed. Thermodynamic quantities are determined. Pleiades Publishing, Ltd., 2012.
Selective photocatalytic oxidation of aromatic alcohols in solar-irradiated aqueous suspensions of Pt, Au, Pd and Ag loaded TiO2 catalysts
Yurdakal, Sedat,Tek, Bilge Sina,De?irmenci, ?a?lar,Palmisano, Giovanni
, p. 53 - 59 (2017)
The photocatalytic partial oxidation of 4-methoxybenzyl alcohol (MBA) and 4-nitrobenzyl alcohol (NBA) to corresponding aldehydes or acids was performed in water under simulated solar light at different pH's by using Pt, Au, Pd and Ag loaded Degussa P25 TiO2 catalysts, prepared by photoreduction. Bare Degussa P25 TiO2 was also used as a reference. The metal loaded TiO2 photocatalysts were characterized by XRD, TEM, ESEM and DRS techniques. The best activity and selectivity results were obtained with Pt loaded TiO2. The reactivity results show that metal loading on Degussa P25 sharply promotes the photoactivity and product selectivity towards aldehydes. Moreover, at low pH's very high aldehyde selectivities were determined for both alcohols. MBA oxidation rate was very high at low pH's, whereas an opposite trend was observed for NBA, due to the difference of the substituent group. Only from NBA a significant amount 4-nitrobenzoic acid (ca. 50%) was obtained at high pH values.
Three N-stabilized rhodamine-based fluorescent probes for Al3+ via Al3+-promoted hydrolysis of Schiff bases
Ding, Peigang,Wang, Jinhui,Cheng, Junye,Zhao, Yufen,Ye, Yong
, p. 342 - 348 (2015)
Three probes for Al3+ detection by both fluorescence and the naked eye in acetonitrile solution were developed. The mechanism of fluorescence was based on the aluminum complexation with rhodamine and subsequent Al3+-promoted hydrolysis of the Schiff base. Theoretical calculations indicated that the aluminum complexes tend to hydrolyze to compound L6. A simple paper test strip system for the rapid monitoring of Al3+ was developed, indicating its convenient use in environmental samples.
Fluoro-tagged osmium and iridium nanoparticles in oxidation reactions
Santacruz, Lynay,Donnici, Silvia,Granados, Albert,Shafir, Alexandr,Vallribera, Adelina
, p. 6890 - 6895 (2018)
Osmium and iridium metal nanoparticles were supported on a fluorous organic-inorganic hybrid material prepared by the sol-gel process. Moreover, we also found that the thermolysis of the Ir4(CO)12 cluster in simply diphenylether also
Argon plasma reduced Pt nanocatalysts supported on carbon nanotube for aqueous phase benzyl alcohol oxidation
Zhou, Chunmei,Chen, Hong,Yan, Yibo,Jia, Xinli,Liu, Chang-Jun,Yang, Yanhui
, p. 104 - 108 (2013)
Carbon nanotube supported Pt nano-catalyst was prepared by facile glow discharge plasma reduction operated at room temperature. The low-temperature plasma reduced Pt nanoparticles exhibited uniform size distribution and an average particle size of around
Zinc chlorochromate nonahydrate [Zn(ClCrO3)2.9H2O] is a useful reagent for the solvent-free and in solution oxidative deprotection of trimethyl- and tert-butyldimethylsilyl ethers
Firouzabadi, Habib,Gholizadeh, Mostafa,Fakourpour, Mahmood
, p. 81 - 87 (1999)
Primary and secondary tert-butyldimethylsilyl and trimethylsilyl ethers are oxidized to their corresponding carbonyl compounds with zinc chlorochromate nonahydrate (ZCCNH) in dichloromethane or under solvent free conditions in good yields. For comparison, we have also studied the reactions with pyridinium chlorochromate (PCC) under similar reaction conditions.
SECONDARY α-DEUTERIUM ISOTOPE EFFECT ON THE HYDRATION OF THE p-NITROBENZALDEHYDE
Pires, Jose Ricardo,Stachissini, Antonia Sonia,Amaral, Luciano Do
, p. 192 - 195 (1994)
The secondary α-deuterium isotope effect on the equilibrium constant (KD/KH) for the hydration of p-nitrobenzaldehyde is 1.39 +/- 0.05.The kinetic secondary α-deuterium isotope effect (kD/kH) for the addition of water to p-nitrobenzaldehyde is 1.18+/-0.07.This result demonstrates that there is extensive carbon-oxygen bond formation in the transition state for addition of water to the carbonyl group of p-nitrobenzaldehyde.
Synthesis of novel oxime functionalized aldol products via Michael addition of oximes onto Baylis-Hillman adducts
Bhuniya, Debnath,Gujjary, Srinivas,Sengupta, Sujata
, p. 151 - 164 (2006)
Triphenylphosphine-catalyzed Michael addition of oximes 2 onto Baylis-Hillman (B-H) adducts 1 led to an easy access to a novel class of oxime functionalized aldol products 3. This demonstrates the first use of an oxygen-centered nucleophile in Michael addition to B-H adducts, without touching any other functional group. Deprotection of oxime in 3 was further demonstrated using molecular hydrogen (1 atm) and 10% Pd/C (cat.) to furnish functionalized 1,3-diols 4 as potentially useful synthons with optional backbone choice (R 3 and EWG). Copyright Taylor & Francis LLC.
Photochemical generation of acetonitrile oxide via the C-N bond cleavage of 3-methyl-2-(4-nitrophenyl)-2H-azirine
Inui,Murata
, p. 1036 - 1037 (2001)
Acetonitrile oxide (2) is produced by the irradiation of the title azirine 1 in the presence of O2 in fluid solutions and in low-temperature matrices through the capture of the biradical 7 with O2, which is generated by the photochem
