- Effect of CHAPS and CPC micelles on Ir(III) catalyzed Ce(IV) oxidation of aliphatic alcohols at room temperature and pressure
-
Kinetics of cerium(IV) oxidation of aliphatic alcohols: ethanol, propanol, propan-2-ol, 1-butanol and 2-butanol were studied at 30 °C in the presence and absence of surfactants in acidic medium. The reaction was studied under pseudo-first-order conditions
- Ghosh, Aniruddha,Saha, Rumpa,Saha, Bidyut
-
p. 223 - 237
(2014/05/06)
-
- Selective reduction of carboxylic acids to aldehydes catalyzed by B(C 6F5)3
-
B(C6F5)3 efficiently catalyzes hydrosilylation of aliphatic and aromatic carboxylic acids to produce disilyl acetals under mild conditions. Catalyst loadings can be as low as 0.05 mol %, and bulky tertiary silanes are favored to give selectively the acetals. Acidic workup of the disilyl acetals results in the formation of aldehydes in good to excellent yields.
- Bezier, David,Park, Sehoon,Brookhart, Maurice
-
supporting information
p. 496 - 499
(2013/03/29)
-
- Revisiting the reaction of hydroxyl radicals with vicinal diols in water
-
The carbonyl products of the reactions of hydroxyl radicals with three vicinal diols (ethane-1,2-diol, propane-1,2-diol and butane-2,3-diol) have been identified and quantified. Hydroxyl radicals were produced by γ-radiolysis of N2O-saturated aqueous solutions. The reactions result in the formation of alkoxyl radicals (~15%) followed by β-fragmentation, and α-hydroxyl alkyl radicals that undergo H2O elimination. The latter process is part of a radical chain reaction at higher diol concentrations.
- Jiang, Dong,Barata-Vallejo, Sebastian,Golding, Bernard T.,Ferreri, Carla,Chatgilialoglu, Chryssostomos
-
supporting information; experimental part
p. 1102 - 1107
(2012/04/04)
-
- Self- and cross-aldol condensation of propanal catalyzed by anion-exchange resins in aqueous media
-
Carbon-carbon bond formation using strong and weak anion-exchange resins as green catalysts for self- and cross-aldol condensation of propanal in aqueous media was investigated. The reaction pathway followed the route of aldol condensation to a β-hydroxy aldehyde and dehydration to an α,β-unsaturated aldehyde. The resulting products were further converted to hemi-acetal, and/or acetal moieties, which were confirmed by FT-IR and NMR. In self-condensation using strong anion-exchange resin, 97% conversion of propanal was achieved with 95% selectivity to 2-methyl-2-pentenal within 1 h using 0.4 g/mL resin at 35 °C. The conversion and selectivity using weak anion exchanger was lower. During cross-aldol condensation of propanal with formaldehyde, 3-hydroxy-2-methyl-2-hydroxymethylpropanal was obtained as the main product through first and second cross-condensation followed by hydration reaction in acidic aqueous conditions. The strong anion-exchange resin provided maximal propanal conversion of 80.4% to the product with 72.4% selectivity after 7 h reaction at 35 °C and resin concentration of 1.2 g/mL. Using weak anion-exchange resin, the optimal conversion of propanal was 89.9% after 24 h at 0.8 g/mL resin and 35 °C, and the main product was 3-hydroxy-2- methylpropanal by first cross-aldol condensation along with relatively minor amounts of methacrolein and 3-hydroxy-2-methyl-2-hydroxymethylpropanal.
- Pyo, Sang-Hyun,Hedstroem, Martin,Hatti-Kaul, Rajni,Lundmark, Stefan,Rehnberg, Nicola
-
supporting information; experimental part
p. 631 - 637
(2011/12/02)
-
- A novel synthetic method for the preparation of aliphatic aldehydes from the corresponding carboxylic acids
-
A novel synthetic method for the preparation of aliphatic aldehydes from the corresponding carboxylic acids via 1,3-dimethylbenzimidazolium salts is provided. 1,3-Dimethylbenzimidazolium salts were rapidly reduced with sodium/ethanol and then hydrolyzed with hydrochloric acid to obtain aliphatic aldehydes, in which the 1,3-dimethylbenzimidazolium salts can be readily achieved from the corresponding carboxylic acids. The mechanism for the reductive reaction of 1,3-dimethylbenzimidazolium salts with sodium/ethanol was discussed.
- Guo, Yuan,Lu, Zhenhuan,Yao, Libo,Shi, Zhen
-
experimental part
p. 489 - 492
(2012/01/05)
-
- Analysis of carbonyl compounds in sea buckthorn for the evaluation of triglyceride oxidation, by enzymatic hydrolysis and derivatisation methodology
-
Carbonyl compounds formed in sea buckthorn berry (Hippophae rhamnoides) and oil samples as a result of lipid oxidation were determined by enzymatic hydrolysis followed by derivatisation with 2,4-dinitrophenylhydrazine and analysed by LC-UV and electrospra
- Mathew, Sindhu,Grey, Carl,Rumpunen, Kimmo,Adlercreutz, Patrick
-
experimental part
p. 1399 - 1405
(2012/02/03)
-
- Kinetics and mechanism of the oxidation of aliphatic primary alcohols by imidazolium fluorochromate
-
The oxidation of nine aliphatic primary alcohols by imidazolium fluorochromate (IFC) in dimethylsulphoxide leads to the formation of corresponding aldehydes. The reaction is first order with respect to IFC. A Michaelis-Menten type kinetics is observed with respect to alcohols. The reaction is promoted by hydrogen ions; the hydrogen-ion dependence has the form : kobs = a + b [H+]. The oxidation of [1,1- 2H2]ethanol (MeCD2OH) exhibits a substantial primary kinetic isotope effect (kH/kD = 5.87 at 298 K). The reaction has been studied in nineteen different organic solvents. The solvent effect was analysed using Taft's and Swain's multiparametric equations. The rate of oxidation is susceptible to both polar and steric effects of the substituents. A suitable mechanism has been proposed.
- Gehlot,Gilla,Mishra,Sharma, Vinita
-
experimental part
p. 685 - 692
(2012/04/04)
-
- Synthesis, characterization, redox, catalytic, and antibacterial activities of binuclear ruthenium(III) schiff base complexes containing triphenylphosphine as co-ligand
-
New hexa-coordinated binuclear Ru(III) Schiff base complexes of the type [(PPh3)2X2Ru]2L (where, X = Cl or Br; L = binucleating N2O2 Schiff bases) have been synthesized and characterized by elemental analysis, magnetic susceptibility measurement, FT-IR, UV-vis, 13C1H-NMR, ESR, cyclic voltammetric, SEM and powder X-ray diffraction pattern. The new complexes have been used as catalyst in C C coupling reaction and the oxidation of alcohols to their corresponding carbonyl compounds by using molecular oxygen atmosphere at ambient temperature. Further, the new Schiff base ligands and their Ru(III) complexes were also screened for their antibacterial activity against K. pneumoniae, Shigella sp., M. luteus, E. coli and S. typhi. From this study, it was found out that the activity of the ruthenium(III) Schiff base complexes almost reaches the effectiveness of the conventional bacteriocide standards. Copyright Taylor & Francis Group, LLC.
- Manimaran, Arumugam,Jayabalakrishnan, Chinnasamy
-
experimental part
p. 116 - 128
(2010/08/13)
-
- Biocidal and catalytic efficiency of ruthenium(III) complexes with tridentate Schiff base ligands
-
The reaction of the Schiff bases (obtained by condensing isatin with o-aminophenol/o-aminothiophenol/o-aminobenzoic acid) with [RuX 3(EPh3)3] (where X = Cl/Br; E = P/As) in benzene afforded new, air-stable Ru(III) complexes of the general formula [Ru(L)X(EPh3)2] (L = dianion of tridentate Schiff bases). In all these reactions, the Schiff base ligand replaces one triphenylphosphine/ triphenylarsine and two chlorides/bromides from the ruthenium precursors. The complexes were characterized by elemental analyses, spectral (FT-IR, UV-vis,1H and 13C NMR for the ligands, and EPR) and electrochemical studies. All the metal complexes exhibit characteristic LMCT absorption bands in the visible region. The catalytic reactivity proved these complexes to be efficient catalysts in the oxidation of alcohols and C-C coupling. All the complexes were screened for their biocidal efficiency against bacteria such as Staphylococcus epidermidis and Escherichia coli and fungi such as Botrytis cinerea and Aspergillus niger at 0.25,0.50 and 1 % concentrations.
- Arunachalam,Priya, N. Padma,Boopathi,Jayabalakrishnan,Chinnusamy
-
experimental part
p. 491 - 498
(2010/10/18)
-
- Oxidation of aliphatic primary alcohols by morpholinium chlorochromate: A kinetic and mechanistic approach
-
The oxidation of nine aliphatic primary alcohols by morpholinium chlorochromate (MCC) in dimethylsulfoxide leads to the transformation of alcohols to the corresponding aldehydes. The reaction is first order with respect to both MCC and the alcohol both. The reaction is catalysed by hydrogen ions. The hydrogen-ion dependence has the form: kobs = a + A[H +]. The oxidation of [1,1-2H2]ethanol (MeCD2OH) exhibits a substantial primary kinetic isotope effect. The reaction has been studied in nineteen different organic solvents. The solvent effect was analysed using Taft's and Swain's multiparametric equations. The rate of oxidation is susceptible to both polar and steric effects of the substituents. A suitable mechanism has been proposed.
- Choudhary,Yajurvedi,Soni,Agarwa,Sharma, Vinita
-
experimental part
p. 1061 - 1066
(2011/05/05)
-
- Quantitative RP-HPLC determination of some aldehydes and hydroxyaldehydes as their 2,4-dinitrophenylhydrazone derivatives
-
A high-performance liquid chromatographic (HPLC) method is described for the quantitative determination of some aliphatic aldehydes and β- hydroxyaldehydes as their 2,4-dinitrophenylhydrazone derivatives. A method is described for the preparation of deriv
- Koivusalmi,Haatainen,Root
-
-
- AUTOOXIDATION OF ACETYLENES AND THEIR DERIVATIVES. XXV. 1-PHENYL-4-PENTEN-1-YN-3-0L AND 1-PHENYL-4-HEXEN-1-YN-3-OL
-
During the autooxidation of secondary enynyl alcohols attack by oxygen takes place at the C-H bonds at the α position to the triple and double bonds and the hydroxyl group.The initially formed unstable hydroxyhydroperoxides dissociate under the oxidation conditions into the corresponding enynyl ketones, acetylenic keto epoxydes, and products from degradation of the carbon skeleton.
- Stepin, S. G.,Tishchenko, I. G.
-
p. 1771 - 1774
(2007/10/02)
-
- KINETICS OF THE FORMATION OF 2,4-DINITROPHENYLHYDRAZONES IN HYDROCARBONS
-
The kinetics of the formation of 2,4-dinitrophenylhydrazones in a hydrocarbon medium were studied.By an integral method it was found that the reaction of carbonyl compounds with 2,4-dinitrophenylhydrazine is reversible, and the forward and reverse reactio
- Kuznetsova, E. V.,Mil'kina, T. N.,Morzhakova, T. M.,Taranenko, S. A.,Kudinova, L. M.,Batalin, O. E.
-
p. 1914 - 1918
(2007/10/02)
-
- Determination of Nanogram Amounts of Carbonyls as 2,4-Dinitrophenylhydrazones by High-Performance Liguid Chromatography
-
A simple method has been developed for the separation and quantitation of nanogram amounts of carbonyl compounds including aliphatic, unsaturated, and aromatic carbonyls as well as dicarbonyls and other difunctional carbonyls.This method entails the separ
- Fung, Kochy,Grosjean, Daniel
-
p. 168 - 171
(2007/10/02)
-