- Preparation method of diethyl methylmalonate by taking heteropolyacid as catalyst
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The invention relates to a preparation method of diethyl methylmalonate by taking heteropolyacid as a catalyst. The method comprises the following steps: adding 2-cyanopropionic acid into ethanol fordissolving, controlling the molar ratio of 2-cyanopropionic acid to ethanol to be 1:(3-4), and transferring the obtained solution into a reaction kettle after dissolving; stirring at room temperature,adding the heteropolyacid catalyst, controlling the mass ratio of 2-cyanopropionic acid to the heteropolyacid catalyst to be 2:(1-2), controlling the temperature to be 65-80 DEG C, reacting for 3-4 h, and then ending the reaction; distilling to separate ethanol, adding ammonia water to neutralize, regulating the pH value to be neutral, and fractionating to obtain crude diethyl methylmalonate; andputting the crude diethyl methylmalonate into a rectifying tower, and carrying out reduced pressure rectification to obtain diethyl methylmalonate. Sulfuric acid is replaced with the heteropolyacid catalyst for an esterification reaction, so the method has the advantages of good selectivity, high catalytic activity, high regeneration speed and small corrosion to equipment.
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Paragraph 0013-0020
(2020/05/01)
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- NAPHTHYRIDINES AS INHIBITORS OF HPK1
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Naphthyridine compounds and their use as inhibitors of HPK1 are described. The compounds are useful in treating HPK1-dependent disorders and enhancing an immune response. Also described are methods of inhibiting HPK1, methods of treating HPK1-dependent disorders, methods for enhancing an immune response, and methods for preparing the naphthyridine compounds.
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Paragraph 0859; 0860
(2018/10/21)
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- Enantioselective α-Alkylation of Aldehydes by Photoredox Organocatalysis: Rapid Access to Pharmacophore Fragments from β-Cyanoaldehydes
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The combination of photoredox catalysis and enamine catalysis has enabled the development of an enantioselective α-cyanoalkylation of aldehydes. This synergistic catalysis protocol allows for the coupling of two highly versatile yet orthogonal functionalities, allowing rapid diversification of the oxonitrile products to a wide array of medicinally relevant derivatives and heterocycles. This methodology has also been applied to the total synthesis of the lignan natural product (-)-bursehernin. A combination of photoredox catalysis and enamine catalysis has enabled the development of an enantioselective cyanoalkylation of aldehydes. This synergistic catalysis protocol makes possible the coupling of two highly versatile yet orthogonal functionalities.
- Welin, Eric R.,Warkentin, Alexander A.,Conrad, Jay C.,MacMillan, David W. C.
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supporting information
p. 9668 - 9672
(2015/08/11)
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- PEPTIDOMIMETIC COMPOUNDS AND ANTIBODY-DRUG CONJUGATES THEREOF
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This invention relates to peptidomimetic linkers and anti-body drug conjugates thereof, to pharmaceutical compositions containing them, and to their use in therapy for the prevention or treatment of cancer.
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Page/Page column 118
(2015/07/07)
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- Active template synthesis of rotaxanes and molecular shuttles with switchable dynamics by four-component PdII-promoted Michael additions
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(Chemical Equation). Taking the Michael: Rotaxanes (see structure) and molecular shuttles are prepared in up to 99% yield by successive Pd II-promoted 1,4-conjugate additions in a one-pot four-component assembly process. This process represents the first active template reaction in which the template motif is retained in the interlocked product.
- Goldup, Stephen M.,Leigh, David A.,Lusby, Paul J.,McBurney, Roy T.,Slawin, Alexandra M. Z.
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supporting information; experimental part
p. 3381 - 3384
(2009/02/07)
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- CO2 anion-radical in organic carboxylations
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This letter shows a first approximation to the use of CO2 anion-radical in the obtention of α-methyl and α-ethylcyanoacetic acids from propionitrile and butyronitrile, respectively, through a paired electrochemical reaction with CO2. The electrosynthesis of α-chloro-phenylacetic acid from benzyl chloride and phenylacetic acid from toluene by another proposed pathway is also discussed.
- Otero, M. Dolores,Batanero, Belen,Barba, Fructuoso
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p. 2171 - 2173
(2007/10/03)
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- Asymmetric Michael reaction of α-cyano carboxylates catalyzed by a rhodium complex with trans-chelating chiral diphosphine PhTRAP
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Asymmetric Michael reaction of 2-cyanopropionates with vinyl ketones or acrolein in the presence of 0.1-1 mol% of a rhodium catalyst prepared in situ from RhH(CO)(PPh3)3 and a trans-chelating chiral diphosphine ligand (S,S)- (R,R)-PhTRAP in benzene at 3-5 °C gave optically active Michael adducts with high enantiomeric excesses (83-93% ee) in high yields. The reaction of 2- cyanopropionate with methacrolein and crotonaldehyde proceeded somewhat slowly, giving diastereomer mixtures in moderate enantioselectivities but in low diastereoselectivities. The reaction of 2-cyanobutyrate and 2-cyano-3- methylbutyrate with acrolein gave corresponding Michael adducts with much lower enantiomeric excesses than that of 2-cyanopropionates. The Michael addition product from acrolein was converted into an optically active α- methyl-α-amino acid.
- Sawamura, Masaya,Hamashima, Hitoshi,Ito, Yoshihiko
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p. 4439 - 4454
(2007/10/02)
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