851866-86-9Relevant academic research and scientific papers
Preparation method of 3, 3-dimethyl-2-oxobutyric acid and triazinone
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Paragraph 0055-0056; 0058-0059; 0061-0062; 0064-0065; 0067, (2021/06/23)
The invention relates to the field of pesticides, and discloses a preparation method of 3, 3-dimethyl-2-oxobutyric acid and triazinone. The preparation method of the 3, 3-dimethyl-2-oxobutyric acid provided by the invention comprises the step of oxidizing the 3, 3-dimethyl-2-oxobutyric acid and/or a salt thereof by taking oxygen-containing gas as an oxidizing agent in the presence of a catalyst under the condition that the pH value is 7-13. According to the method disclosed by the invention, the 3, 3-dimethyl-2-hydroxybutyric acid and/or the salt thereof is taken as the raw material, and oxygen or air is used for replacing other oxidants, so that high-salinity wastewater and solid waste are avoided, the cost of the raw material is reduced, and the method is simple to operate and suitable for industrial production.
Stereoselective Modification of N-(α-Hydroxyacyl)-glycinesters via Palladium-Catalyzed Allylic Alkylation
Horn, Alexander,Kazmaier, Uli
supporting information, p. 4595 - 4599 (2019/06/27)
N-(α-Hydroxyacyl)-glycinesters can be used as excellent nucleophiles in Pd-catalyzed allylic alkylation. The method allows for the stereoselective introduction of a wide range of side chains, including highly functionalized ones. Both diastereomers can be accessed through variation of the reaction conditions. Furthermore, the use of stannylated carbonates introduces vinylstannane motifs, which are eligible for subsequent C-C coupling reactions.
Preparation method of 3,3-dimethyl-2-oxobutyric acid
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Paragraph 0035; 0037, (2018/10/04)
The invention relates to a preparation method of 3,3-dimethyl-2-oxobutyric acid, and belongs to the technical field of pharmaceutical intermediate synthesis. In order to solve the problems of seriouspollution and low yield of the existing synthetic route, the invention provides a preparation method of 3,3-dimethyl-2-oxobutyric acid, and the method comprises: halogenating 3,3-dimethyl butyric acidwith a halogenating agent in an organic solvent to obtain an intermediate product; then carrying out a hydrolysis reaction to obtain a corresponding hydrolyzed product; and in the presence of TEMPO catalyst, oxidizing the hydrolyzed product under the action of an oxidant, and then carrying out acidification to obtain a product 3,3-dimethyl-2-oxobutyric acid. According to the preparation method provided by the invention, a mixed catalyst of a noble metal catalyst and a transition metal catalyst is avoided, the environmental pollution and the cost are reduced, and the effects of high yield andhigh purity can still be ensured.
Readily Accessible 1,2-Amino Ether Ligands for Enantioselective Intramolecular Carbolithiation
Guyon, Hélène,Boussonnière, Anne,Castanet, Anne-Sophie
, p. 4949 - 4957 (2017/05/12)
A new class of chiral 1,2-amino ether ligands, readily accessible from naturally occurring α-amino- or α-hydroxy acids, was found to provide high levels of both conversion and stereocontrol (up to 95:5 er) in intramolecular carbolithiation reactions, outperforming the benchmark ligand (?)-sparteine. The ligand could be used in a substoichiometric amount (0.25 equiv) without significant loss of enantioselectivity.
Janadolide, a Cyclic Polyketide-Peptide Hybrid Possessing a tert-Butyl Group from an Okeania sp. Marine Cyanobacterium
Ogawa, Hidetoshi,Iwasaki, Arihiro,Sumimoto, Shinpei,Kanamori, Yuki,Ohno, Osamu,Iwatsuki, Masato,Ishiyama, Aki,Hokari, Rei,Otoguro, Kazuhiko,Omura, Satoshi,Suenaga, Kiyotake
, p. 1862 - 1866 (2016/08/02)
Janadolide, a new cyclic polyketide-peptide hybrid possessing a tert-butyl group, was isolated from an Okeania sp. marine cyanobacterium. The gross structure was elucidated by spectroscopic analyses, and the absolute configurations of the amino acid moieties were determined by acid hydrolysis and chiral-phase HPLC analyses. The absolute configuration of the two stereogenic centers in the polyketide moiety was elucidated based on a combination of degradation reactions and spectroscopic analyses including the phenyl-glycine methyl ester method. Janadolide showed potent antitrypanosomal activity with an IC50 value of 47 nM without cytotoxicity against human cells at 10 μM.
Asymmetric hydrogenation reaction of alpha-ketoacids compound
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Paragraph 0037; 0044, (2016/10/10)
The invention relates to the technical field of organic chemistry, especially to an asymmetric hydrogenation reaction of an alpha-ketoacids compound. The asymmetric hydrogenation reaction comprises a scheme shown in the description. In the scheme, R1 is phenyl, substituted phenyl, naphthyl, substituted naphthyl, C1-C6 alkyl, or aralkyl; a substituent group is C1-C6 alkyl, C1-C6 alkoxy, or halogen; and the number of the substituent group is 1-3. In the scheme, M is a chiral spiro-pyridylamino phosphine ligand iridium complex having a structure shown in the description. In the structure, R is hydrogen, 3-methyl, 4-tBu, or 6-methyl.
Metal-free one-pot α-carboxylation of primary alcohols
Van Der Heijden, Gydo,Kraakman, Jasper,Biemolt, Jasper,Ruijter, Eelco,Orru, Romano V. A.
supporting information, p. 9716 - 9719 (2016/10/31)
An efficient metal-free procedure for the formal α-carboxylation of primary alcohols has been developed. The method involves a one-pot oxidation/Passerini/hydrolysis sequence and provides access to α-hydroxy acids bearing a broad range of functional groups. A minor modification to the reaction conditions extends the range of accessible products to α-hydroxy esters.
Chiral propargylic cations as intermediates in SN1-type reactions: Substitution pattern, nuclear magnetic resonance studies, and origin of the diastereoselectivity
Nitsch, Dominik,Huber, Stefan M.,Poethig, Alexander,Narayanan, Arjun,Olah, George A.,Prakash, G. K. Surya,Bach, Thorsten
, p. 2851 - 2857 (2014/03/21)
Nine propargylic acetates, bearing a stereogenic center (-C*HXR 2) adjacent to the electrophilic carbon atom, were prepared and subjected to SN1-type substitution reactions with various silyl nucleophiles employing bismuth trifluoromethanesulfonate [Bi(OTf)3] as the Lewis acid. The diastereoselectivity of the reactions was high when the alkyl group R2 was tertiary (tert-butyl), irrespective of the substituent X. Products were formed consistently with a diastereomeric ratio larger than 95:5 in favor of the anti-diastereoisomer. If the alkyl substitutent R2 was secondary, the diastereoselectivity decreased to 80:20. The reaction was shown to proceed stereoconvergently, and the relative product configuration was elucidated. The reaction outcome is explained by invoking a chiral propargylic cation as an intermediate, which is preferentially attacked by the nucleophile from one of its two diastereotopic faces. Density functional theory (DFT) calculations suggest a preferred conformation in which the group R2 is almost perpendicular to the plane defined by the three substituents at the cationic center, with the nucleophile approaching the electrophilic center opposite to R2. Transition states calculated for the reaction of allyltrimethylsilane with two representative cations support this hypothesis. Tertiary propargylic cations with a stereogenic center (-C* HXR2) in the α position were generated by ionization of the respective alcohol precursors with FSO3H in SO2ClF at -80 C. Nuclear magnetic resonance (NMR) spectra were obtained for five cations, and the chemical shifts could be unambiguously assigned. The preferred conformation of the cations as extracted from nuclear Overhauser experiments is in line with the preferred conformation responsible for the reaction of the secondary propargylic cations.
Direct asymmetric hydrogenation of α-keto acids by using the highly efficient chiral spiro iridium catalysts
Yan, Pu-Cha,Xie, Jian-Hua,Zhang, Xiang-Dong,Chen, Kang,Li, Yuan-Qiang,Zhou, Qi-Lin,Che, Da-Qing
supporting information, p. 15987 - 15990 (2015/02/19)
A new efficient and highly enantioselective direct asymmetric hydrogenation of α-keto acids employing the Ir/SpiroPAP catalyst under mild reaction conditions has been developed. This method might be feasible for the preparation of a series of chiral α-hydroxy acids on a large scale.
Reaction intermediate analogues as bisubstrate inhibitors of pantothenate synthetase
Xu, Zhixiang,Yin, Wei,Martinelli, Leonardo K.,Evans, Joanna,Chen, Jinglei,Yu, Yang,Wilson, Daniel J.,Mizrahi, Valerie,Qiao, Chunhua,Aldrich, Courtney C.
, p. 1726 - 1735 (2014/03/21)
The biosynthesis of pantothenate, the core of coenzyme A (CoA), has been considered an attractive target for the development of antimicrobial agents since this pathway is essential in prokaryotes, but absent in mammals. Pantothenate synthetase, encoded by the gene panC, catalyzes the final condensation of pantoic acid with β-alanine to afford pantothenate via an intermediate pantoyl adenylate. We describe the synthesis and biochemical characterization of five PanC inhibitors that mimic the intermediate pantoyl adenylate. These inhibitors are competitive inhibitors with respect to pantoic acid and possess submicromolar to micromolar inhibition constants. The observed SAR is rationalized through molecular docking studies based on the reported co-crystal structure of 1a with PanC. Finally, whole cell activity is assessed against wild-type Mtb as well as a PanC knockdown strain where PanC is depleted to less than 5% of wild-type levels.
