Aldehydes

Distribution by Scientific Domains
Distribution within Chemistry

Kinds of Aldehydes

  • aliphatic aldehyde
  • alkyl aldehyde
  • amino aldehyde
  • aromatic aldehyde
  • aryl aldehyde
  • branched aldehyde
  • chiral aldehyde
  • cinnamic aldehyde
  • corresponding aldehyde
  • different aldehyde
  • epoxy aldehyde
  • of aldehyde
  • peptide aldehyde
  • reactive aldehyde
  • salicylic aldehyde
  • total aldehyde
  • unsaturated aldehyde
  • variety of aldehyde
  • various aldehyde
  • volatile aldehyde

  • Terms modified by Aldehydes

  • aldehyde Catalyze
  • aldehyde dehydrogenase
  • aldehyde functionality
  • aldehyde group
  • aldehyde groups
  • aldehyde oxidase
  • aldehyde substrate

  • Selected Abstracts


    Organocatalytic Three-Component Reactions of Pyruvate, Aldehyde and Aniline by Hydrogen-Bonding Catalysts

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 25 2008
    Xin Li
    Abstract Hydrogen-bonding catalysts have been found to catalyze one-pot three-component reactions of pyruvate, anilines and aldehydes to afford versatile 3-amino-1,5-dihydro-2H -pyrrol-2-ones in high yields. Both, thioureas and phosphoric acids are viable catalysts for these reactions and have comparable activity. The corresponding chiral thioureas and phosphoric acids have also been used in these three-component reactions to give pyrrol-2-ones in high yields and with moderate enantioselectivities.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source]


    Silica-Immobilized NHC,CuI Complex: An Efficient and Reusable Catalyst for A3 -Coupling (Aldehyde,Alkyne,Amine) under Solventless Reaction Conditions

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 13 2008
    Min Wang
    Abstract A novel silica-immobilized NHC,CuI complex was developed and used as a highly efficient catalyst in the three-component coupling reactions of aldehydes, alkynes and amines (A3 -coupling). The reactions were applicable to aromatic and aliphatic aldehydes, alkynes and amines, and generated the corresponding propargylamines in good yields only in the presence of SiO2,NHC,CuI (2 mol-%) at room temp. under solvent-free reaction conditions. Moreover, the catalyst was quantitatively recovered from the reaction mixture by a simple filtration and reused for ten cycles with almost consistent activity.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source]


    Allylation of Aldehyde and Imine Substrates with In Situ Generated Allylboronates , A Simple Route to Enatioenriched Homoallyl Alcohols

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 12 2005
    Sara Sebelius
    Abstract Allylation of aldehyde and imine substrates was achieved using easily available allylacetates and diboronate reagents in the presence of catalytic amounts of palladium. This operationally simple one-pot reaction has a broad synthetic scope, as many functionalities including, acetate, carbethoxy, amido and nitro groups are tolerated. The allylation reactions proceed with excellent regio- and stereoselectivity affording the branched allylic isomer. By employment of commercially available chiral diboronates enantioenriched homoallyl alcohols (up to 53,% ee) could be obtained. The mechanistic studies revealed that the in situ generated allylboronates react directly with the aldehyde substrates, however the allylation of the sulfonylimine substrate requires palladium catalysis. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source]


    Facile Assembly of H -Pyrazolo[5,1- a]isoquinolines via Silver Triflate-Catalyzed One-Pot Tandem Reaction of 2-Alkynyl- benzaldehyde, Sulfonohydrazide, and Ketone or Aldehyde

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2010
    Xingxin Yu
    Abstract A novel and efficient route for the generation of H -pyrazolo[5,1- a]isoquinolines via silver triflate-catalyzed one-pot tandem reaction of 2-alkynylbenzaldehyde, sulfonohydrazide, and ketone or aldehyde is described. This reaction proceeds with good functional group tolerance under mild conditions with high efficiency and excellent selectivity. [source]


    Semiconductor-Gold Nanocomposite Catalysts for the Efficient Three-Component Coupling of Aldehyde, Amine and Alkyne in Water

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 17 2009
    Leng Leng Chng
    Abstract An efficient heterogeneous lead sulfide-gold catalyst has been successfully developed for the synthesis of propargylic amines via a three-component coupling reaction of aldehyde, amine and alkyne in water. The process is simple and applicable to a diverse range of aromatic and aliphatic aldehydes, amines and alkynes. Furthermore, the catalyst is stable to air and water, and can be easily recovered and reused. [source]


    Photocatalytic Selective Oxidation of 4-Methoxybenzyl Alcohol to Aldehyde in Aqueous Suspension of Home-Prepared Titanium Dioxide Catalyst

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 6 2007
    Giovanni Palmisano
    Abstract The photocatalytic oxidation of 4-methoxybenzyl alcohol to p -anisaldehyde (PAA) was performed in water with organic-free suspensions of home-prepared and commercial titanium dioxide (TiO2) catalysts. The nanostructured TiO2 samples were synthesised by boiling aqueous solutions of titanium tetrachloride (TiCl4), under mild conditions, for different times. The crystallinity increased with the boiling time. The 4-methoxybenzyl alcohol oxidation rate followed the same pattern but the highest yield (41.5,% mol) to PAA was found for the least crystalline sample, that showed a quantum efficiency of 0.116,%. A comparison with two commercial TiO2 samples showed that all the home-prepared catalysts exhibited a PAA yield higher than that of commercial ones. The only by-products present were traces of 4-methoxybenzoic acid and aliphatic products, carbon dioxide being the other main oxidation product. [source]


    The Direct, Enantioselective, One-Pot, Three-Component, Cross-Mannich Reaction of Aldehydes: The Reason for the Higher Reactivity of Aldimine versus Aldehyde in Proline-Mediated Mannich and Aldol Reactions

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-13 2005
    Yujiro Hayashi
    Abstract In the proline-mediated Mannich and aldol reactions of propanal as a nucleophile, the aldimine prepared from benzaldehyde and p -anisidine is about 7 times more reactive than the corresponding aldehyde, benzaldehyde, as an electrophile. This higher reactivity of aldimine over aldehyde is attributed to the carboxylic acid of proline protonating the basic nitrogen atom of the aldimine more effectively than the oxygen atom of the aldehyde, an explanation which has been both experimentally and theoretically verified. [source]


    Sodium Perborate,A Convenient Baeyer,Villiger Oxidation Reagent in the Synthesis of the Corey Aldehyde

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 3 2003
    Maria Espiritu
    Abstract Sodium perborate tetrahydrate is a cheap, safe and readily available alternative to the commonly used peracetic acid for the Baeyer,Villiger oxidation step of the Corey aldehyde synthesis. Chloroketo acid 1 is smoothly converted by sodium perborate tetrahydrate in formic acid to the chloroketolactone 2 in 66% isolated yield. In contrast to previously reported reactions using other oxidants, the formation of the lactone is completely regioselective in favour of the "bridgehead-migrated" isomer 2. [source]


    Oxidation and epoxidation of poly(1,3-cyclohexadiene)

    JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 1 2003
    D. T. Williamson
    Abstract Poly(1,3-cyclohexadiene) (PCHD) derivatives were synthesized via facile chemical modification reactions of the residual double bond in the repeat unit. The oxidation and degradation of PCHD was investigated to enable subsequent controlled epoxidation reactions. PCHD exhibited a 15% weight loss at 110 °C in the presence of oxygen. The oxidative degradation, demonstrated by gel permeation chromatography (GPC) and 1H NMR spectroscopy, was attributed to main-chain scission. Aldehyde and ether functional groups were introduced into the polymer during the oxidation process. PCHD was quantitatively epoxidized in the absence of deleterious oxidation with meta -chloroperoxybenzoic acid. 1H and 13C NMR spectroscopy confirmed that polymers with controlled degrees of epoxidation were reproducibly obtained. Epoxidized PCHD exhibited a glass-transition temperature at 154 °C, which was slightly higher than that of a PCHD precursor of a nearly equivalent molecular weight. Moreover, GPC indicated the absence of undesirable crosslinking or degradation, and the molecular weight distributions remained narrow. The thermooxidative stability of the fully epoxidized polymer was compared to that of the PCHD precursor, and the epoxidized PCHD exhibited an initial weight loss at 250 °C in oxygen, which was 140 °C higher than the temperature for PCHD. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 84,93, 2003 [source]


    The Reaction of Organozinc Compounds with an Aldehyde within a Crystalline Molecular Flask,

    ANGEWANDTE CHEMIE, Issue 33 2010
    Koki Ikemoto
    Ein Organozinkreagens wurde im Zuge einer Einkristall-Einkristall-Umwandlung im Innern eines porösen Koordinationsgerüsts an einen Aldehyd addiert (siehe Bild). Dabei wurde die Struktur des Produkts durch Röntgenbeugung abgesichert. Eine zweistufige Reaktion im Einkristall überführte darüber hinaus einen Aldehyd in einen Ester, ohne dass die Kristallinität des Gerüsts verlorenging. [source]


    MgCl2 -beschleunigte Additionen von funktionalisierten Organozinkreagentien an Aldehyde, Ketone und Kohlendioxid,

    ANGEWANDTE CHEMIE, Issue 27 2010
    Albrecht Metzger Dipl.-Chem.
    Magnesium wirkt leistungssteigernd: Die geringe Reaktivität von Organozinkreagentien gegenüber Aldehyden, Ketonen und CO2 kann durch MgCl2 erhöht werden, das normalerweise während der Erzeugung der Zinkreagentien gebildet wird. Speziell die direkte Reaktion mit CO2 eröffnet einen einfachen Weg zu Phenylessigsäurederivaten, wie die kurze Synthese von Ibuprofen veranschaulicht. [source]


    Tunable Bromomagnesium Thiolate Tishchenko Reaction Catalysts: Intermolecular Aldehyde,Trifluoromethylketone Coupling,

    ANGEWANDTE CHEMIE, Issue 17 2010
    Linda Cronin Dr.
    Angewandtes Wissen: Eine neue Thiolat-katalysierte Tischtschenko-Reaktion, die an einen biochemischen Prozess angelehnt ist, bietet eine außerordentlich gute Kontrolle über die sterischen und elektronischen Eigenschaften des Katalysators. Die Isolierung von Reaktionszwischenstufen brachte Erkenntnisse zum Reaktionsmechanismus, die als Grundlage für die Entwicklung der ersten gekreuzten Tischtschenko-Kupplung zwischen Aldehyden und aktivierten Ketonen dienten (siehe Beispiel). [source]


    Eine praktische und hochreaktive polyfluorierte hypervalente Iod(III)-Verbindung,

    ANGEWANDTE CHEMIE, Issue 15 2010
    Sascha Schäfer Dr.
    Hyper-reaktiv: Eine hoch reaktive, vollständig fluorierte hypervalente Iodverbindung (siehe Strukturformel) ermöglicht neue Reaktionen (z.,B. eine Eintopf-Synthese von Sulfoximinen ausgehend von Sulfiden) und wurde auch als stöchiometrisches Oxidationsmittel bei etablierten Reaktionen (z.,B. bei C-C-Bindungsspaltungen und der Umwandlung von Alkoholen in Aldehyde) eingesetzt. [source]


    Enantioselective Intermolecular Aldehyde,Ketone Cross-Coupling through an Enzymatic Carboligation Reaction,

    ANGEWANDTE CHEMIE, Issue 13 2010
    Patrizia Lehwald
    Ein höchst nützliches Enzym ist der ThDP-abhängige Enzymkatalysator, mit dem die Titelreaktion gelang. Seine außerordentlich breite Substratpalette umfasst cyclische und offenkettige Ketone, Diketone sowie ,- und ,-Ketoester als Akzeptorsubstrate. Die Absolutkonfigurationen von zwei Enzymprodukten wurden durch Einkristall-Röntgenstrukturanalyse ermittelt. [source]


    Eine Cobalt-katalysierte Sulfonat/Kupfer-Austauschreaktion zur Synthese von elektronenarmen, hoch funktionalisierten Arylkupferreagentien,

    ANGEWANDTE CHEMIE, Issue 10 2010
    Christoph
    Organokupferreagentien aus Phenolen: Unter milden Reaktionsbedingungen (25,45,°C, 1,6,h) gelingt die Synthese präparativ wertvoller Arylkupferverbindungen aus elektronenarmen Arylsulfonaten (siehe Beispiel). Empfindliche funktionelle Gruppen wie Aldehyde, Ester oder Nitrile werden toleriert. [source]


    Copper-Catalyzed Hydrosilylation with a Bowl-Shaped Phosphane Ligand: Preferential Reduction of a Bulky Ketone in the Presence of an Aldehyde,

    ANGEWANDTE CHEMIE, Issue 8 2010
    Tetsuaki Fujihara Prof.
    Sperriges zuerst: Ein hoch aktiver Kupferkatalysator mit einem schalenförmigen Phosphanliganden (bsp) vermittelt eine bislang einzigartige Reaktion: die Hydrosilylierung von sperrigen Ketonen in Gegenwart eines ungeschützten Aldehyds. [source]


    Atomically Precise Au25(SR)18 Nanoparticles as Catalysts for the Selective Hydrogenation of ,,,-Unsaturated Ketones and Aldehydes,

    ANGEWANDTE CHEMIE, Issue 7 2010
    Yan Zhu Dr.
    Eine glänzende Gelegenheit: Eine Erklärung für den chemoselektiven Verlauf der Hydrierung ,,,-ungesättigter Ketone (oder Aldehyde) zu ungesättigten Alkoholen mit monodispersen Au25(SR)18 -Partikeln als Katalysator wird vorgeschlagen (siehe Bild). Dank der nun bekannten Struktur dieser Nanopartikel können Struktur-Aktivitäts-Beziehungen aufgestellt werden. [source]


    Highly Enantioselective Hydrophosphonylation of Aldehydes: Base-Enhanced Aluminum,salalen Catalysis,

    ANGEWANDTE CHEMIE, Issue 4 2010
    Keitaro Suyama
    Mit Dimethylphosphonat ließen sich zahlreiche konjugierte und nichtkonjugierte Aldehyde in Gegenwart des chiralen Aluminium-Salalen-Komplexes 1 zu ,-Hydroxyphosphonaten mit 93,98,%,ee hydrophosphonylieren (siehe Schema). [source]


    Titelbild: Fast Prediction of Selectivity in Heterogeneous Catalysis from Extended Brønsted,Evans,Polanyi Relations: A Theoretical Insight (Angew. Chem.

    ANGEWANDTE CHEMIE, Issue 47 2009
    47/2009)
    Brønsted-Evans-Polanyi-Beziehungen sind im Bereich der heterogenen Katalyse bekannt für die schnelle Vorhersage von Aktivierungsbarrieren allein mit Kenntnis der Reaktionsenthalpien. Dieses Modell wurde nun von D. Loffreda et,al. auf die Hydrierung ungesättigter Aldehyde an Platin erweitert. In ihrer Zuschrift auf S.,9140,ff. finden die Autoren auf Grundlage von Dichtefunktionalrechnungen eine lineare Beziehung zwischen der Aktivierungsbarriere und der Stabilität des Vorstufenzustands. [source]


    Fast Prediction of Selectivity in Heterogeneous Catalysis from Extended Brønsted,Evans,Polanyi Relations: A Theoretical Insight,

    ANGEWANDTE CHEMIE, Issue 47 2009
    David Loffreda Dr.
    Lineare Beziehungen werden beobachtet, wenn man für die Hydrierung ungesättigter Aldehyde an Platinoberflächen die Energien der Übergangszustände () gegen die Energien der Vorstufenzustände () aufträgt (siehe Bild; FS=Endzustand). Mithilfe dieser Beziehung können die Energiebarrieren substituierter Derivate schnell und genau ermittelt werden, sobald die Reaktivität der Stammverbindung bekannt ist. [source]


    Aldehyde,alcohol dehydrogenase and/or thiolase overexpression coupled with CoA transferase downregulation lead to higher alcohol titers and selectivity in Clostridium acetobutylicum fermentations

    BIOTECHNOLOGY & BIOENGINEERING, Issue 1 2009
    Ryan Sillers
    Abstract Metabolic engineering (ME) of Clostridium acetobutylicum has led to increased solvent (butanol, acetone, and ethanol) production and solvent tolerance, thus demonstrating that further efforts have the potential to create strains of industrial importance. With recently developed ME tools, it is now possible to combine genetic modifications and thus implement more advanced ME strategies. We have previously shown that antisense RNA (asRNA)-based downregulation of CoA transferase (CoAT, the first enzyme in the acetone-formation pathway) results in increased butanol to acetone selectivity, but overall reduced butanol yields and titers. In this study the alcohol/aldehyde dehydrogenase (aad) gene (encoding the bifunctional protein AAD responsible for butanol and ethanol production from butyryl-CoA and acetyl-CoA, respectively) was expressed from the phosphotransbutyrylase (ptb) promoter to enhance butanol formation and selectivity, while CoAT downregulation was used to minimize acetone production. This led to early production of high alcohol (butanol plus ethanol) titers, overall solvent titers of 30 g/L, and a higher alcohol/acetone ratio. Metabolic flux analysis revealed the likely depletion of butyryl-CoA. In order to increase then the flux towards butyryl-CoA, we examined the impact of thiolase (THL, thl) overexpression. THL converts acetyl-CoA to acetoacetyl-CoA, the first step of the pathway from acetyl-CoA to butyryl-CoA, and thus, combining thl overexpression with aad overexpression decreased, as expected, acetate and ethanol production while increasing acetone and butyrate formation. thl overexpression in strains with asRNA CoAT downregulation did not significantly alter product formation thus suggesting that a more complex metabolic engineering strategy is necessary to enhance the intracellular butyryl-CoA pool and reduce the acetyl-CoA pool in order to achieve improved butanol titers and selectivity. Biotechnol. Bioeng. 2009;102: 38,49. © 2008 Wiley Periodicals, Inc. [source]


    ChemInform Abstract: Fe3O4 Nanoparticles: A Robust and Magnetically Recoverable Catalyst for Three-Component Coupling of Aldehyde, Alkyne and Amine.

    CHEMINFORM, Issue 34 2010
    Tieqiang Zeng
    No abstract is available for this article. [source]


    ChemInform Abstract: Copper-Catalyzed Hydrosilylation with a Bowl-Shaped Phosphane Ligand: Preferential Reduction of a Bulky Ketone in the Presence of an Aldehyde.

    CHEMINFORM, Issue 26 2010
    Tetsuaki Fujihara
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]


    ChemInform Abstract: Semiconductor-Gold Nanocomposite Catalysts for the Efficient Three-Component Coupling of Aldehyde, Amine and Alkyne in Water.

    CHEMINFORM, Issue 12 2010
    Leng Leng Chng
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]


    ChemInform Abstract: Gallium(III) Chloride Catalyzed Three-Component Coupling of Naphthol, Alkyne and Aldehyde: A Novel Synthesis of 1,3-Disubstituted-3H-benzo[f]chromenes.

    CHEMINFORM, Issue 5 2010
    J. S. Yadav
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]


    ChemInform Abstract: Catalytic Intermolecular Aldehyde,Ketone Coupling via Acyl Phosphonates.

    CHEMINFORM, Issue 30 2009
    Ayhan S. Demir
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]


    ChemInform Abstract: Metal-Mediated Diastereoselective Allylation Reaction of Chiral ,,,-Epoxy Aldehyde.

    CHEMINFORM, Issue 6 2009
    Part 2.
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]


    ChemInform Abstract: Reactions of Methyl 4-Hetaryl-2,4-dioxobutanoates with a Mixture of Aminoazole and Aromatic (Heteroaromatic) Aldehyde.

    CHEMINFORM, Issue 1 2009
    V. L. Gein
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]


    ChemInform Abstract: An Efficient and Chemoselective Synthesis of Aldehyde 1,1-Diacetates Using Morpholinium Bisulfate as a Broensted Acidic Ionic Liquid under Solvent-Free Conditions.

    CHEMINFORM, Issue 52 2008
    Abdol Reza Hajipour
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]


    Silica-Immobilized CuI: An Efficient Reusable Catalyst for Three-Component Coupling Reaction of Aldehyde, Amine and Alkyne.

    CHEMINFORM, Issue 52 2007
    Pravin R. Likhar
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source]