3913-71-1Relevant articles and documents
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.
Dehydrogenative Synthesis of Linear α,β-Unsaturated Aldehydes with Oxygen at Room Temperature Enabled by tBuONO
Wang, Mei-Mei,Ning, Xiao-Shan,Qu, Jian-Ping,Kang, Yan-Biao
, p. 4000 - 4003 (2017/06/19)
Synthesis of linear α,β-unsaturated aldehydes via a room-temperature oxidative dehydrogenation has been realized by the cocatalysis of an organic nitrite and palladium with molecular oxygen as the sole clean oxidant. Linear α,β-unsaturated aldehydes could be efficiently prepared under aerobic catalytic conditions directly from the corresponding saturated linear aldehydes. Besides linear products, the aromatic analogy could also be smoothly achieved by the same standard method. The organic nitrite redox cocatalyst and alcohol solvent play a key role for realizing this method.
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
Solvent-Free Aerobic Epoxidation of Dec-1-ene Using Gold/Graphite as a Catalyst
Gupta, Upendra Nath,Dummer, Nicholas F.,Pattisson, Samuel,Jenkins, Robert L.,Knight, David W.,Bethell, Donald,Hutchings, Graham J.
, p. 689 - 696 (2015/08/04)
The oxidation of dec-1-ene has been investigated using gold nanoparticles supported on graphite in the presence of a radical initiator (α,α-azobisisobutyronitrile) using oxygen from air as oxidant. We have investigated the influence of the reaction temperature (70-100 °C), catalyst mass and reaction time on the epoxide yield. In the absence of a radical initiator the reaction does not proceed, although auto-oxidation can occur at higher temperatures in the range studied. However, in the presence of an initiator, selective oxidation occurs and the initiator propagates the reaction through the formation of a peroxy-radical at the allylic C3 position. Graphite enhances the formation of the allylic products dec-1-en-3-ol, dec-1-en-3-one, and dec-2-en-1-ol; however, the addition of gold nanoparticles to the graphite, enhances formation of 1,2-epoxydecane. It is suggested that gold suppresses the formation of allylic products via a Russell termination. Graphical Abstract: [Figure not available: see fulltext.]
A detailed identification study on high-temperature degradation products of oleic and linoleic acid methyl esters by GC-MS and GC-FTIR
Berdeaux, Olivier,Fontagné, Stéphanie,Sémon, Etienne,Velasco, Joaquin,Sébédio, Jean Louis,Dobarganes, Carmen
experimental part, p. 338 - 347 (2012/06/29)
GC-MS and GC-FTIR were complementarily applied to identify oxidation compounds formed under frying conditions in methyl oleate and linoleate heated at 180 °C. The study was focused on the compounds that originated through hydroperoxide scission that remain attached to the glyceridic backbone in fats and oils and form part of non-volatile molecules. Twenty-one short-chain esterified compounds, consisting of 8 aldehydes, 3 methyl ketones, 4 primary alcohols, 5 alkanes and 1 furan, were identified. In addition, twenty non-esterified volatile compounds, consisting of alcohols, aldehydes and acids, were also identified as major non-esterified components. Furanoid compounds of 18 carbon atoms formed by a different route were also identified in this study. Overall, the composition of the small fraction originated from hydroperoxide scission provides a clear idea of the complexity of the new compounds formed during thermoxidation and frying.
A highly regio- and stereoselective cascade annulation of enals and benzodi(enone)s catalyzed by N-heterocyclic carbenes
Fang, Xinqiang,Jiang, Kun,Xing, Chong,Hao, Lin,Chi, Yonggui Robin
supporting information; experimental part, p. 1910 - 1913 (2011/04/16)
Three stereogenic centers in a row: The unconventional activation of enal compounds mediated by an N-heterocyclic carbene (NHC) has generated three consecutive reactive carbon centers that undergo highly regio- and stereoselective annulations with di(enone)s to generate benzotricyclic products containing multiple stereogenic centers (see scheme).
Aerobic oxidation of primary aliphatic alcohols to aldehydes catalyzed by a palladium(II) polyoxometalate catalyst
Barats, Delina,Neumann, Ronny
scheme or table, p. 293 - 298 (2010/04/28)
A hexadecyltrimethylammonium salt of a "sandwich" type polyoxometalate has been used as a ligand to attach a palladium(II) center. This Pd-POM compound was an active catalyst for the fast aerobic oxidation of alcohols. The unique property of this catalyst is its significant preference for the oxidation of primary versus secondary aliphatic alcohols. Since no kinetic isotope effect was observed for the dehydrogenation step, this may be the result of the intrinsically higher probability for oxidation of primary alcohols attenuated by steric factors as borne out by the higher reactivity of 1-octanol versus 2-ethyl-1-hexanol. The reaction is highly selective to aldehyde with little formation of carboxylic acid; autooxidation is inhibited. No base is required to activate the alcohol. The fast reactions appear to be related to the electron-acceptor nature of the polyoxometalate ligand that may also facilitate alcohol dehydrogenation in the absence of base.
New phosphonate reagents for aldehyde homologation
Petroski, Richard J.
, p. 3841 - 3854 (2008/02/10)
New phosphonate reagents were developed for the two-carbon homologation of aldehydes to unbranched or methyl-branched unsaturated aldehydes. The phosphonate reagents, diethyl methylformylphosphonate dimethylhydrazone and diethyl ethylformyl-2-phosphonate dimethylhydrazone, contained a protected aldehyde group instead of the usual ester group. A homologation cycle entailed condensation of the reagent with the starting aldehyde, followed by removal of the dimethylhydrazone protective group with a biphasic mixture of 1 M HCl and petroleum ether. This robust two-step process worked with aliphatic, α,β-unsaturated and aromatic aldehydes. Isolated yields for the condensation step ranged from 77% to 89%, and yields for the deprotection step ranged from 81% to 96%. Copyright Taylor & Francis Group, LLC.
