• trimer
  • In contrast, at low pH, only low quantities of the trimer are produced and the nature of the applied acid has a distinct effect on the reaction outcome. (rsc.org)
  • Complex organic acids, such as e.g. maleic or nicotinic acid, lead to comparable quantities of the trimer and acetaldehyde. (rsc.org)
  • react
  • In the journal Nucleic Acids Research, scientists from the National Institute on Alcohol Abuse and Alcoholism (NIAAA) and the National Institute of Standards and Technology (NIST) report that polyamines "" natural compounds essential for cell growth "" react with acetaldehyde to trigger a series of reactions that damage DNA, an event that can lead to the formation of cancer. (redorbit.com)
  • adducts
  • Dr. Brooks says, "We concluded that polyamines stimulated the formation of Cr-PdG adducts from acetaldehyde, and this may provide a mechanism to explain how alcohol consumption increases the risk of some types of cancer. (redorbit.com)
  • Flavanol-anthocyanin adducts are formed during wine ageing through reactions between anthocyanins and tannins present in grape, with yeast metabolites such as acetaldehyde. (wikipedia.org)
  • salts
  • This reaction is catalyzed by mercury(II) salts: C2H2 + Hg2+ + H2O → CH3CHO + Hg The mechanism involves the intermediacy of vinyl alcohol, which tautomerizes to acetaldehyde. (wikipedia.org)
  • The hydroformylation of methanol with catalysts like cobalt, nickel, or iron salts also produces acetaldehyde, although this process is of no industrial importance. (wikipedia.org)
  • catalyst
  • This process typically is conducted over a silver catalyst at about 500-650 °C. CH3CH2OH + ​1⁄2 O2 → CH3CHO + H2O This method is one of the oldest routes for the industrial of preparation of acetaldehyde. (wikipedia.org)
  • Traditionally, acetaldehyde was produced by the partial dehydrogenation of ethanol: CH3CH2OH → CH3CHO + H2 In this endothermic process, ethanol vapor is passed at 260-290 °C over a copper-based catalyst. (wikipedia.org)
  • The distinct advantages of this process are that the reaction can be a one stage process, the catalyst is regenerated, and concerns about safety, corrosion, and the environment are diminished. (chemcases.com)
  • Hydroxypivalic acid neopentyl glycol ester is produced by a Tishchenko reaction from hydroxypivaldehyde in the presence of a basic catalyst (e.g., aluminium oxide). (wikipedia.org)
  • The key step in the reaction mechanism for this reaction is a 1,3-hydride shift in the hemiacetal intermediate formed from two successive nucleophilic addition reactions, the first one from the catalyst. (wikipedia.org)
  • aldehydes
  • NIOSH recommends that the producers and users of acetaldehyde, malonaldehyde, and the other low-molecular-weight aldehydes disseminate this information to workers and customers. (cdc.gov)
  • room temperature
  • IUPAC name: ethenol): CH3CH=O ⇌ CH2=CHOH ∆H298,g = +42.7 kJ/mol The equilibrium constant is 6×10−7 at room temperature, thus that the relative amount of the enol form in a sample of acetaldehyde is very small. (wikipedia.org)
  • At room temperature, acetaldehyde (CH3CH=O) is more stable than vinyl alcohol (CH2=CHOH) by 42.7 kJ/mol: Overall the keto-enol tautomerization occurs slowly but is catalyzed by acids. (wikipedia.org)
  • When iodine and sodium hydroxide are used as the reagents a positive reaction gives iodoform, which is a solid at room temperature and tends to precipitate out of solution causing a distinctive cloudiness. (wikipedia.org)
  • feedstock
  • Also, research and development, marketing and planning personnel, chemical industry administrators who wish to increase their knowledge and experience of the chemical reactions, feedstock, markets, key players, and basic economics of the industry. (mennta.com)
  • chemical
  • Available kinetic parameters for the most important chemical reactions are reviewed and an updated reaction model is proposed. (deepdyve.com)
  • The new reaction model enables reproducing most of the trends observed experimentally and constitutes an overall improvement as compared to standard detailed chemical models including Aramco 2.0, CaltechMech, and JetSurf. (deepdyve.com)
  • However, some studies indicate that their chemical reactivity and mutagenicity are similar to those of acetaldehyde and malonaldehyde. (cdc.gov)
  • section describes the catalytic activity of an enzyme, i.e. the chemical reaction it catalyzes. (uniprot.org)
  • Basic to these relationships are chemical reactions, and fundamental to the total business is economics. (mennta.com)
  • This reaction forms the basis of the iodoform test which was commonly used in history as a chemical test to determine the presence of a methyl ketone, or a secondary alcohol oxidizable to a methyl ketone. (wikipedia.org)
  • Aromatization is a chemical reaction in which an aromatic system is formed. (wikipedia.org)
  • compounds
  • observed a very stable neutral tetrahedral intermediate in the reaction of N-acylpyrroles with organometallic compounds, followed by protonation with ammounium chloride producing a carbinol. (wikipedia.org)
  • There is a concern that such reactions may lead to the presence of carcinogenic compounds in drinking water. (wikipedia.org)
  • Benzene
  • Kekulé suggested in reply that benzene had two complementary structures and that these forms rapidly interconverted, which would also explain the lack of addition reactions (as the valency of each carbon atom is not that expected of a double bond). (wikipedia.org)
  • reagents
  • Victor Grignard assumed the existence of unstable tetrahedral intermediate in 1901, while investigating the reaction of esters with organomagnesium reagents. (wikipedia.org)
  • intermediate
  • A tetrahedral intermediate is a reaction intermediate in which the bond arrangement around an initially double-bonded carbon atom has been transformed from trigonal to tetrahedral. (wikipedia.org)
  • At the end of the reaction he found that the remaining starting material had a decreased proportion of labeled oxygen, which is consistent with the existence of the tetrahedral intermediate. (wikipedia.org)
  • At least in some cases (chloral hydrate) the reaction may stop and the intermediate product isolated if conditions are acidic and hypohalite is used. (wikipedia.org)
  • Methyl
  • The Tishchenko reaction of paraformaldehyde in the presence of aluminum methylate or magnesium methylate forms methyl formate. (wikipedia.org)
  • concentration
  • NIOSH therefore considers acetaldehyde and malonaldehyde to be potential occupational carcinogens and recommends that exposures to each be reduced to the lowest feasible concentration. (cdc.gov)
  • molecules
  • The research team, led by P.J. Brooks, Ph.D., of NIAAA and Miral Dizdaroglu, Ph.D., of NIST, examined acetaldehyde's reaction with polyamines, small molecules found in all cells. (redorbit.com)
  • It is altered with wine aging by reactions between different active molecules present in the wine, these reactions generally giving rise to a browning of the wine, leading from red to a more tawny color. (wikipedia.org)
  • process
  • The reaction is conducted at 90-95 °C, and the acetaldehyde formed is separated from water and mercury and cooled to 25-30 °C. In the wet oxidation process, iron(III) sulfate is used to reoxidize the mercury back to the mercury(II) salt. (wikipedia.org)
  • produce
  • The potential for acetaldehyde or malonaldehyde to produce cancer in humans has not been determined, but reducing occupational exposures to these chemicals should lower the risk. (cdc.gov)
  • The reaction can be used to transform acetyl groups into carboxyl groups or to produce chloroform (CHCl3), bromoform (CHBr3), or iodoform (CHI3). (wikipedia.org)
  • found
  • Yet the researchers found the polyamines facilitated the conversion of acetaldehyde into crotonaldehyde (CrA), an environmental pollutant that has been shown to cause cancer in animals. (redorbit.com)
  • known
  • View all proteins of this organism that are known to be involved in the subpathway that synthesizes D-glyceraldehyde 3-phosphate and acetaldehyde from 2-deoxy-alpha-D-ribose 1-phosphate , the pathway 2-deoxy-D-ribose 1-phosphate degradation and in Carbohydrate degradation . (uniprot.org)
  • The enzyme catalyzing this reaction is triose phosphate isomerase, one of the most efficient enzymes known. (oregonstate.edu)
  • The nuclear magnetic resonance spectrum shows that there are three environments for protons, in the ratio of 3:2:1 corresponding to CH3 SH and CH. 1,1-Ethanedithiol has several reactions known that are important in white wine flavours. (wikipedia.org)