71277-05-9Relevant academic research and scientific papers
Formation of potentially toxic carbonyls during oxidation of triolein in the presence of alimentary antioxidants
Damanik, Marini,Murkovic, Michael
, p. 2031 - 2035 (2017/10/26)
Abstract: A relation between oil uptake and cancer as well as induction of hepatic inflammation was shown earlier. It is discussed that the main oil oxidation products—hydroperoxides and carbonyls—might be the reason for the mentioned diseases. In this manuscript quantitative determination of aldehydes which are formed during oxidation of triolein—as a model substance—using the Rancimat 679 is described. The oxidation of 11?g of triolein is carried out at 120?°C sparging air with a flow of 20?dm3/h for 10?h. A series of aliphatic aldehydes starting from hexanal to decanal as well as decenal was identified by LC–MS/MS and quantified as DNPH derivatives. In addition, the total amount of carbonyls was determined. Based on the calibration with hexanal, all other dominant substances were in the similar concentration range with maximum concentrations of 1.6?μmol/cm3 of hexanal, 2.3?μmol/cm3 of heptanal, 2.5?μmol/cm3 of octanal, 3.2?μmol/cm3 of nonanal, 4.0?μmol/cm3 of decanal after 6?h. The total amount of carbonyls reached a maximum after 6?h being 27?μmol/cm3 for triolein without antioxidant. The results of this investigation will be a basis for further toxicological studies on oxidized oils.
Method to oxidize alcohols selectively to aldehydes and ketones with heterogeneous supported ruthenium catalyst at room temperature in air and catalyst thereof
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Paragraph 0021; 0022, (2016/10/07)
The present invention relates to a method for selectively oxidizing alcohol by using a heterogeneous catalyst for producing aldehyde and ketone in an organic synthesis process used in the laboratory and chemical industries, and a catalytic system thereof. The method can be used as an intermediate product for synthesizing medicine, scent, fragrance, and precise chemical products, and can use a heterogeneous catalyst at room temperature in air by using the catalytic system and producing alcohol and ketone.COPYRIGHT KIPO 2016
Selective oxidation of styrene catalyzed by cerium-doped cobalt ferrite nanocrystals with greatly enhanced catalytic performance
Tong, Jinhui,Li, Wenyan,Bo, Lili,Wang, Huan,Hu, Yusen,Zhang, Zhixia,Mahboob, Abdulla
, p. 474 - 481 (2016/11/18)
The rare earth metal Ce-doped cobalt ferrite samples CexCo1?xFe2O4 (x?=?0.1, 0.3, 0.5) were prepared by the sol–gel autocombustion route. The as-prepared samples were characterized by X-ray diffractometry, scanning electron microscopy, transmission electron microscopy, ICP–atomic emission spectroscopy, and N2 physisorption. Their catalytic performance was evaluated in oxidation of styrene using hydrogen peroxide (30%) as oxidant. Compared with pristine CoFe2O4, the Ce-doped samples were found to be more efficient catalysts for the oxidation of styrene to benzaldehyde, with greatly enhanced catalytic performance. Especially, when Ce0.3Co0.7Fe2O4 was used as catalyst, 90.3% styrene conversion and 91.5% selectivity for benzaldehyde were obtained at 90?°C for 9?h reaction. The catalyst can be magnetically separated easily for reuse, and no obvious loss of activity was observed when it was reused in five consecutive runs.
PpoC from Aspergillus nidulans is a fusion protein with only one active haem
Brodhun, Florian,Schneider, Stefan,Goebel, Cornelia,Hornung, Ellen,Feussner, Ivo
experimental part, p. 553 - 565 (2011/02/23)
In Aspergillus nidulans Ppos [psi (precocious sexual inducer)-producing oxygenases] are required for the production of so-called psi factors, compounds that control the balance between the sexual and asexual life cycle of the fungus. The genome of A. nidulans harbours three different ppo genes: ppoA, ppoB and ppoC. For all three enzymes two different haem-containing domains are predicted: a fatty acid haem peroxidase/ dioxygenase domain in the N-terminal region and a P450 haem-thiolate domain in the C-terminal region. Whereas PpoA was shown to use both haem domains for its bifunctional catalytic activity (linoleic acid 8-dioxygenation and 8-hydroperoxide isomerization), we found that PpoC apparently only harbours a functional haem peroxidase/dioxygenase domain. Consequently, we observed that PpoC catalyses mainly the dioxygenation of linoleic acid (18:2Δ 9Z,12Z), yielding 10-HPODE (10-hydroperoxyoctadecadienoic acid). No isomerase activity was detected. Additionally, 10-HPODE was converted at lower rates into 10-KODE (10-keto-octadecadienoic acid) and 10-HODE (10-hydroxyoctadecadienoic acid). In parallel, decomposition of 10-HPODE into 10-ODA (10-octadecynoic acid) and volatile C-8 alcohols that are, among other things, responsible for the characteristic mushroom flavour. Besides these principle differences we also found that PpoA and PpoC can convert 8-HPODE and 10-HPODE into the respective epoxy alcohols: 12,13-epoxy-8-HOME (where HOME is hydroxyoctadecenoic acid) and 12,13-epoxy-10-HOME. By using site-directed mutagenesis we demonstrated that both enzymes share a similar mechanism for the oxidation of 18:2Δ9Z,12Z; they both use a conserved tyrosine residue for catalysis and the directed oxygenation at the C-8 and C-10 is most likely controlled by conserved valine/leucine residues in the dioxygenase domain. The Authors Journal compilation
Copper-catalyzed rearrangement of vinyl oxiranes
Batory, Lindsay A.,McInnis, Christine E.,Njardarson, Jon T.
, p. 16054 - 16055 (2007/10/03)
A novel copper-catalyzed vinyl oxirane ring expansion protocol has been developed. A wide range of vinyl oxiranes can be rearranged to 2,5-dihydrofurans in excellent yields in the presence of electrophilic copper(II) acetylacetonate catalysts. Regioisomeric vinyl oxiranes can be converted to a single dihydrofuran product using these conditions. This method uses low catalyst loadings (0.5-5 mol %), has good tolerance of substitution patterns, and can be done in the absence of solvent. Copyright
Synthesis of α,β-unsaturated aldehydes and methyl carboxylic esters from 2-acetylenic phenyl sulfides
Fortes, Carlos C.,Garrote, Clevia F. D.
, p. 3917 - 3941 (2007/10/03)
2-Alkynylthio benzenes were reduced to 2-Alkenylthio benzenes with diisobutyl aluminum hydride. Mono chlorination of these compounds with sulfuryl chloride and pyridine followed by hydrolysis, in the presence of Cu(II) salts, gave α,β-unsaturated aldehydes. 2-Alkynylthio benzenes were converted into 2-Alkynyl 1,1-bis thiobenzenes by monochlorination with sulfuryl chloride and pyridine followed by treatment with thiophenol and triethylamine. These substances were then converted to α,β-unsaturated methyl carboxylic esters by way of isomerization with sodium methoxide to the corresponding allene and treatment with hydrochloric acid and methanolysis in the presence of iodine.
Synthesis of carbonyl and dicarbonyl compounds from organometallic reagents and N-imidazolium-N-methyl amides and bis-amides
De Las Heras, Maria A.,Vaquero, Juan J.,Garcia Navio, Jose L.,Alvarez-Builla, Julio
, p. 14297 - 14310 (2007/10/03)
A new method for the synthesis of selective acylating agents is described from the reaction of carboxylic acids with 3-methyl-1-methylamino-3H-imidazol-1-ium salts in the presence of appropriate coupling reagents. The amides and bis-amides thus prepared reacted selectively with organometallics to afford ketones and diketones and with DIBALH to give aldehydes and dialdehydes in high yields.
Oxidative Breaking of Long-Chain Acetylenic Enol Ethers of Glycerol of the Marine Sponges Raspailia pumila and R. ramosa and of Model Compounds with Aerial Oxygen
Guella, Graziano,Mancini, Ines,Pietra, Francesco
, p. 1400 - 1411 (2007/10/02)
The raspailynes (novel long-chain enol ethers of glycerol having the enol ether double bond conjugated, in sequence, to an acetylenic and an olefinic bond, isolated from the North-East-Atlantic sponges Raspailia pumila and R. ramosa) are stable under normal hydrolytic conditions for enol ethers.In contrast, when their solutions are evaporated, these lipids such as raspailyne B1 (=(-)-3--1,2-propanediol; (-)-2) rapidly react with aerial O2 under normal laboratory-daylight conditions, with rupture of the C=C enol ether bond to give 1-O-formylglycerol (3) and an aldehyde (such as tridec-4-en-3-ynal(4) from (-)-2).This reaction must be caused by triplet O2, since thermally generated singlet O2 has no effect on (-)-2 in solution.That the mere presence of an enol-ether moiety conjugated to an acetylenic group is responsible for such a behaviour is demonstrated with the model compounds 1-methoxypentadec-1-en-3-yn-5-ol (6a) and its 5-O-acetyl or 5-O-tetrahydropyranyl derivatives 6b and 6c, respectively.Resistance to both hydrolytic conditions and singlet O2 of these compounds is thought to arise from electron depletion at the enol-ether C(β) atom by the acetylenic group.Plausible reaction pathways for enol-ether bond rupture in these compounds by aerial O2 are outlined.
Reactions with Phosphine Alkylenes, 44. A Further Synthesis of (Z)-α,β-Unsaturated Aldehydes
Bestmann, Hans Juergen,Ermann, Peter
, p. 3264 - 3266 (2007/10/02)
Reaction of phosphorus ylides 4, especially such with electron donating groups R, with the glyoxal semiacetal 5 leads Z-stereospecifically to the formation of the acetals 3, which can be cleaved to the (Z)-α,β-unsaturated aldehydes 6.
Cumulated Ylides, XII. A Stereoselective Synthetic Method for (Z)-α,β-Unsaturated Aldehydes
Bestmann, Hans Juergen,Roth, Kurt,Ettlinger, Manfred
, p. 161 - 171 (2007/10/02)
(2-Ethoxyvinyl)triphenylphosphonium bromide (5) is converted with sodium amide into the corresponding phosphaallenylide 6 which adds ethanol forming the ylide 7. 7 is also obtained by the reaction of 5 with sodium ethanolate.The Wittig reaction of 7 with aldehydes 2 proceeds with high (Z)-stereoselectivity to give (Z)-α,β-unsaturated acetals 8 which are cleaved under well defined conditions with p-toluenesulfonic acid or with wet silica gel to (Z)-α,β-unsaturated aldehydes 9.
