- Lactones as minor products of the electrochemical reduction of glutaryl dichloride at mercury cathodes in acetonitrile
-
Electrochemical reduction of glutaryl dichloride at a mercury electrode in acetonitrile containing 0.1 M tetraethylammonium perchlorate results in the formation of 5-chlorovalerolactone, valerolactone, and a polymeric species.
- Urove, Greg A.,Peters, Dennis G.
-
-
Read Online
- Remote stereocontrol as a synthetic strategy: Diastereoselective annulations on an arene tricarbonylchromium template
-
Stereoselective annulations on Cr(CO)3 complexed tetralone and benzosuberone derivatives have been achieved. Diastereomeric products are shown to be related by an epimerisable chiral centre. An unusually facile de-ethoxycarbonylation has been observed.
- Sur, Surojit,Ganesh, Sambasivam,Puranik, Vedavati G.,Sarkar, Amitabha
-
-
Read Online
- A NEW SYNTHESIS OF CARBOXYLIC AND CARBONIC ACID ANHYDRIDES USING PHASE TRANSFER REACTIONS
-
Acyl chlorides and alkylchloroformates smoothly reacted with one molar equivalent of sodium hydroxide, using liquid-liquid phase transfer conditions to afford high yields of the corresponding symmetrical carboxylic and carbonic hemiester anhydrides.Unstable anhydrides such as 4-nitrobenzoic, 2-furoic and methacrylic anhydrides, which are otherwise difficult to obtain, were easily prepared by this method.The reaction mechanism does not seem to involve intermediate hydrolysis of half the acid chloride into the corresponding sodium carboxylate.
- Plusquellec, Daniel,Roulleau, Fabienne,Lefeuvre, Martine,Brown, Eric
-
-
Read Online
- METHOD FOR PRODUCING CARBOXYLIC ACID ANHYDRIDE OR SULFONIC ACID ANHYDRIDE
-
To provide a method for producing carboxylic acid anhydride or sulfonic acid anhydride in which carboxylic acid anhydride or sulfonic acid anhydride is produced in a simple or easy process using carboxylic acid or sulfonic acid as raw material, and using an industrially available raw material and in an efficient process in industrial practice.SOLUTION: Provided is a method for producing carboxylic acid anhydride or sulfonic acid anhydride, which is a method for producing an acid anhydride by reacting carboxylic acid or sulfonic acid and a halogenating agent, and in which a solvent containing a phosphoric acid ester such as the formula (1) is used. (R1, R2 and R3 are the same or non-identical alkyl group or fluorine-containing alkyl group having 1 to 10 carbon atoms, and at least one is fluorine-containing alkyl group.).SELECTED DRAWING: None
- -
-
Paragraph 0042-0045; 0048-0049
(2021/02/25)
-
- Heterogeneous catalysts for the cyclization of dicarboxylic acids to cyclic anhydrides as monomers for bioplastic production
-
Cyclic anhydrides, key intermediates of carbon-neutral and biodegradable polyesters, are currently produced from biomass-derived dicarboxylic acids by a high-cost multistep process. We present a new high-yielding process for the direct intramolecular dehydration of dicarboxylic acids using a reusable heterogeneous Lewis acid catalyst, Nb2O5·nH2O. Various dicarboxylic acids, which can be produced by a biorefinery process, are transformed into the corresponding cyclic anhydrides as monomers for polyester production. This method is suitable for the production of renewable polyesters in a biorefinery process.
- Rashed, Md. N.,Siddiki,Ali, Md. A.,Moromi, Sondomoyee K.,Touchy, Abeda S.,Kon, Kenichi,Toyao, Takashi,Shimizu, Ken-Ichi
-
p. 3238 - 3242
(2017/07/28)
-
- 4-Biphenylalanine- and 3-Phenyltyrosine-Derived Hydroxamic Acids as Inhibitors of the JumonjiC-Domain-Containing Histone Demethylase KDM4A
-
Overexpression of the histone lysine demethylase KDM4A, which regulates H3K9 and H3K36 methylation states, has been related to the pathology of several human cancers. We found that a previously reported hydroxamate-based histone deacetylase (HDAC) inhibitor (SW55) was also able to weakly inhibit this demethylase with an IC50value of 25.4 μm. Herein we report the synthesis and biochemical evaluations, with two orthogonal in vitro assays, of a series of derivatives of this lead structure. With extensive chemical modifications on the lead structure, also by exploiting the versatility of the radical arylation with aryldiazonium salts, we were able to increase the potency of the derivatives against KDM4A to the low-micromolar range and, more importantly, to obtain demethylase selectivity with respect to HDACs. Cell-permeable derivatives clearly showed a demethylase-inhibition-dependent antiproliferative effect against HL-60 human promyelocytic leukemia cells.
- Morera, Ludovica,Roatsch, Martin,Fürst, Michael C. D.,Hoffmann, Inga,Senger, Johanna,Hau, Mirjam,Franz, Henriette,Schüle, Roland,Heinrich, Markus R.,Jung, Manfred
-
p. 2063 - 2083
(2016/10/22)
-
- Reactions of hydrogen peroxide with acetylacetone and 2- acetylcyclopentanone
-
A reaction of acetylacetone with equimolar amount of concentrated aqueous H2O2 in both organic solvents (ButOH, AcOH) and water at various temperatures gave the corresponding 3,5-dihydroxy-1,2- dioxolanes with different configuration of stereogenic centers. In the pres-ence of an excess of H2O2, 3,5-dihydroxy-1,2-dioxolanes were converted to a mixture of 5-hydroperoxy-3-hydroxy-1,2-dioxolanes and further to a mixture of dimeric 1,2-dioxolan-3-ylperoxides. All the peroxides formed exist in solutions as equilibrium mixtures with the starting reagents. A prolonged reflux of solutions of 3,5-dihydroxy-1,2-dioxolanes in ButOH in the presence of a large excess of H2O2 led to the skeletal rearrangements of the substrates to a mixture of propionic acid and hydroxyacetone, which underwent further oxidative transfor-mations. Unlike acetylacetone, 2-acetylcyclopentanone reacted with H2O2 in aqueous phase or in solutions in ButOH under thermodynamic or kinetic control with the formation of the corresponding 5-hydroperoxy-3-hydroxy- 1,2-dioxolanes, rather than 3,5-dihydroxy-1,2-di-oxolanes. Thermodynamically controlled process in solution in AcOH gave a mixture of all four possible hydroperoxyhydroxy-1,2-dioxolanes. These cyclic peroxides in solutions in ButOH or AcOH readily converted to a mixture of AcOH, glutaric, α-methyladipic, and α-hydroxy-α-methyladipic acids. An active α-hydroxylation of the substrate was observed upon reflux of a solution of 2-acetylcyclopentanone and H2O2 in AcOH.
- Novikov,Shestak
-
p. 2171 - 2190
(2014/11/07)
-
- Homobivalent ligands of the atypical antipsychotic clozapine: Design, synthesis, and pharmacological evaluation
-
To date all typical and atypical antipsychotics target the dopamine D 2 receptor. Clozapine represents the best-characterized atypical antipsychotic, although it displays only moderate (submicromolar) affinity for the dopamine D2 receptor. Herein, we present the design, synthesis, and pharmacological evaluation of three series of homobivalent ligands of clozapine, differing in the length and nature of the spacer and the point of attachment to the pharmacophore. Attachment of the spacer at the N4′ position of clozapine yielded a series of homobivalent ligands that displayed spacer-length-dependent gains in affinity and activity for the dopamine D 2 receptor. The 16 and 18 atom spacer bivalent ligands were the highlight compounds, displaying marked low nanomolar receptor binding affinity (1.41 and 1.35 nM, respectively) and functional activity (23 and 44 nM), which correspond to significant gains in affinity (75- and 79-fold) and activity (9- and 5-fold) relative to the original pharmacophore, clozapine. As such these ligands represent useful tools with which to investigate dopamine receptor dimerization and the atypical nature of clozapine.
- McRobb, Fiona M.,Crosby, Ian T.,Yuriev, Elizabeth,Lane, J. Robert,Capuano, Ben
-
supporting information; experimental part
p. 1622 - 1634
(2012/04/17)
-
- Thermal and photochemical oxidation of 2-acetylcyclopentanone with atmospheric oxygen
-
The major products of thermal (acetone, CaCl2 excess, reflux) and photochemical (acetone or CCl4, room temperature) oxidation of 2-acetylcyclopentanone with atmospheric oxygen are 2-acetyl-2- hydroxycyclopentanone, 2-acetyl-2-hydroxy
- Novikov,Shestak
-
p. 1099 - 1110
(2013/07/26)
-
- Efficient and convenient synthesis of symmetrical carboxylic anhydrides from carboxylic acids with sulfated zirconia by phase transfer catalysis
-
An efficient and convenient procedure for the synthesis of symmetrical carboxylic anhydrides from carboxylic acids with sulfated zirconia by PEG-1000 phase transfer catalysis has been developed. The reactions proceeded under mild and solvent-free conditions to provide the carboxylic anhydrides in good to excellent yields. The product can be isolated by a simple extraction with organic solvent, and the catalyst system can be recycled or reused without any significant loss of catalytic activity.
- Hu, Yu Lin,Zhao, Xing E.,Lu, Ming
-
experimental part
p. 255 - 262
(2012/04/17)
-
- Bronsted base-assisted boronic acid catalysis for the dehydrative intramolecular condensation of dicarboxylic acids
-
Bronsted base-assisted boronic acid catalysis for the dehydrative self-condensation of carboxylic acids is described. Arylboronic acid bearing bulky (N,N-dialkylamino)methyl groups at the 2,6-positions can catalyze the intramolecular dehydrative condensation of di-and tetracarboxylic acids. This is the first successful method for the catalytic dehydrative self-condensation of carboxylic acids.(Figure Presented)
- Sakakura, Akira,Ohkubo, Takuro,Yamashita, Risa,Akakura, Matsujiro,Ishihara, Kazuaki
-
scheme or table
p. 892 - 895
(2011/05/02)
-
- METHOD FOR PRODUCING CARBOXYLIC ANHYDRIDE AND ARYLBORONIC ACID COMPOUND
-
When phthalic acid is heated in heptane under azeotropic reflux conditions in the presence of a catalytic amount of an arylboronic acid compound (such as 2,6-(diisopropylaminomethyl)phenylboronic acid or 2,6-bis(diisopropylaminomethyl)phenylboronic acid), phthalic anhydride is obtained in high yield.
- -
-
Page/Page column 14
(2012/01/13)
-
- Pheromones and analogs from Neozeleboria wasps and the orchids that seduce them: a versatile synthesis of 2,5-dialkylated 1,3-cyclohexanediones
-
Chiloglottone, a wasp pheromone and attractant of sexually deceptive Chiloglottis orchids, and several structural analogs were synthesized. The synthetic approach is facile, high yielding and versatile, enabling rapid divergence to generate dialkylated analogs of chiloglottone. The key transformation was an organocadmium-mediated desymmetrization of glutaric anhydride derivatives. This library of synthetic 2,5-dialkylated 1,3-cyclohexanediones may assist in future identification of natural products in further species.
- Poldy, Jacqueline,Peakall, Rod,Barrow, Russell A.
-
p. 2446 - 2449
(2008/09/20)
-
- Direct hydrogenation of carboxylic acids to corresponding aldehydes catalyzed by palladium complexes
-
A variety of carboxylic acids can be directly hydrogenated into the corresponding aldehydes in high yields by using homogeneous catalysts such as [Pd(PPh3)4] or combination of Pd(OAc)2 with tertiary phosphines in the presence of an excess amount of 2,2-dimethylpropionic anhydride (pivalic anhydride). As a typical example, octanoic acid can be convened into octanal in 99% yield in 3 h at 80 °C under 3.0 MPa of H2 in acetone in the presence of pivalic anhydride and a catalyst system composed of Pd(OAc)2 + 5P(p-tol)3. Such hydrogenation is widely applicable to various aliphatic, aromatic, and heterocyclic carboxylic acids as well as to di- and tribasic carboxylic acids. The process allows the presence of other functional groups such as ketonic carbonyl, nitrile, and ester groups and even internal C=C bonds. Heterogeneous palladium catalyst such as palladium on carbon also showed some catalytic activities.
- Nagayama,Shimizu,Yamamoto
-
p. 1803 - 1815
(2007/10/03)
-
- Asymmetric hydrogenation method of a ketonic compound and derivative
-
The present invention relates to a process for the asymmetric hydrogenation of a ketonic compound and derivative. The invention relates to the use of optically active metal complexes as catalysts for the asymmetric hydrogenation of a ketonic compound and derivative. The process for the asymmetric hydrogenation of a ketonic compound and derivative is characterized in that the asymmetric hydrogenation of said compound is carried out in the presence of an effective amount of a metal complex comprising as ligand an optically active diphosphine corresponding to one of the following formulae: STR1
- -
-
-
- Synthesis of Small-Medium Ring Thioanhydrides
-
Reaction of five-membered ring anhydrides with sodium sulfide has previously been employed for synthesis of the corresponding thioanhydrides in low yields.Re-examination of the stoichiometry reveals reaction of cyclic anhydride with sodium sulfide (2:1 respectively), affords the thioanhydride accompanied by the corresponding dicarboxylate in a 1:1 molar ratio.The mechanistic pathway for this reaction has also been elucidated.Optimization of reaction conditions has resulted in the synthesis of a variety of four to seven-membered ring thioanhydride in yields approaching theoretical.
- Kates, Michael J.,Schauble, J. Herman
-
p. 971 - 978
(2007/10/02)
-
- Clay catalysis: A convenient and rapid formation of anhydride from carboxylic acid and isopropenyl acetate under microwave irradiation
-
The Montmorillonite KSF catalyses the synthesis of anhydrides from carboxylic acids in the presence of isopropenyl acetate under microwave irradiations.
- Villemin,Labiad,Loupy
-
p. 419 - 424
(2007/10/02)
-
- Ozonolyses of Olefins with Chloro Substituents in Vinylic Positions on Polyethylene
-
Ozonolyses of the chloro-substituted 5- and 6-membered cycloolefins 20a, 20b and 30a-c on polyethylene afforded the corresponding chloro-substituted ozonides.The thermal decomposition of these ozonides is described.Ozonolyses of the same olefins in solution and of the acyclic chloro olefins 5 and 8 both on polyethylene and in solution gave no ozonides.
- Griesbaum, Karl,Greinert, Reinhard
-
p. 391 - 397
(2007/10/02)
-
- A Convenient One-Pot Synthesis of Carboxylic Acid Anhydrides Using 1,1'-Oxalyldiimidazole
-
Aliphatic, aromatic, and heteroaromatic carboxylic acids (5a-i) react with 1,1'-oxalyldiimidazole (6) in acetonitrile under reflux in the presence of methanesulfonic acid (12) to give the corresponding carboxylic acid anhydrides (9a-i) in 30-98percent yields.Keywords- dehydration; carboxylic acid anhydride; N-acylimidazole; 1,1'-carbonyldiimidazole; 1,1'-oxalyldiimidazole
- Kitagawa, Tokujiro,Kuroda, Hiroko,Sasaki, Hideaki
-
p. 1262 - 1265
(2007/10/02)
-
- Preparation of Ni- or Pt-Containing Cyclic Esters by Oxidative Addition of Cyclic Carboxylic Anhydrides and Their Properties
-
Metal containing cyclic ester complexes, L (L=1,2-bis(diphenylphosphino)ethane (dpe) or 2,2'-bipyridine (bpy); R1, R2=H or CH3) and Ln )L=tricyclohexylphosphine (PCy3) or dpe; n=1 or 2), have been prepared by oxidative addition of cyclic carboxylic anhydrides to zero-valent metal complexes.These complexes have been characterized by elemental analysis and spectroscopies (IR as well as 1H-, 13C1H>-, and 31P1H>-NMR) and chemical rectivities.Rate of the oxidative addition of succinic anhydride to Ni(bpy)(cod) (cod=1,5-cyclooctadiene) is expressed by a second order rate equation, R=k, and temperature dependence of k gives the activation energy of 68 kJ mol-1.The reaction of methylsuccinic anhydride with Ni(cod)2 in the presence of tertiary phosphine or bpy affords two isomers, Ln and Ln, corresponding to two modes of C-O bond cleavage in methylsuccininc anhydride promoted by Ni; dependence of the ratio between the two isomers on the kind of ligand added and reaction conditions has been examined.
- Sano, Kenji,Yamamoto, Takakazu,Yamamoto, Akio
-
p. 2741 - 2747
(2007/10/02)
-
- PREPARATION OF SEVERAL NEW Ni- OR Pd-CONTAINING CYCLIC AMIDE AND ESTERS, (PR3)nNi(CH2CH2CH2COZ) (Z=NH, O) AND PCy3Pd(CH2CH2CH2COO), AND RING CONTRACTION OF THE SIX-MEMBERED Ni-CONTAINING CYCLIC ESTER TO ITS FIVE-MEMBERED ISOMER
-
New metallacyclic amide and esters (PCy3Ni(CH2CH2CH2CONH), (PR3)nNi(CH2CH2CH2COO), PCy3Pd(CH2CH2CH2COO) ) have been prepared by reactions of zero-valent nickel and palladium complexes with unsaturated amide and acid.The 6-membered Ni-containing cyclic ester undergoes a ring contraction reaction to a 5-membered isomer.
- Sano, Kenji,Yamamoto, Takakazu,Yamamoto, Akio
-
p. 695 - 698
(2007/10/02)
-