1071-46-1Relevant articles and documents
Electrocatalytic carboxylation of aliphatic halides at silver cathode in acetonitrile
Niu, Dong-Fang,Xiao, Li-Ping,Zhang, Ai-Jian,Zhang, Gui-Rong,Tan, Qi-Yun,Lu, Jia-Xing
, p. 10517 - 10520 (2008)
A simple and efficient electrocarboxylation reaction of aliphatic halides has been developed using silver as cathode, magnesium as anode and CH3CN saturated CO2 as solvent in an undivided cell. The influence of some key factors (such as the nature of electrode materials, supporting electrolytes and temperature) on this reaction was investigated. Under the optimized condition, the corresponding carboxylic acids were obtained in moderate to good yields (22-89%). The electrochemical behaviour was studied at different electrodes (Ag, Cu, Ni and Ti) by cyclic voltammetry, which showed significant electrocatalytic effect of the silver electrode towards the reductive carboxylation of aliphatic halides.
First Kilogram-Scale Application of the Lanthanum Catalyzed Asymmetric Amination to Synthesis of the Chiral Succinimide Derivative, A Key Intermediate for the Preparation of AS-3201
Toshima, Minoru,Watanabe, Shoji,Uchiyama, Katsuya,Takasaki, Tsuyoshi,Bhogle, Nandkumar N.,Zhao, Hang,Filios, Mike,Takahashi, Kazuhiko,Snoonian, John R.,Saranteas, Kostas
, p. 1239 - 1245 (2016)
The process development of ethyl-(R)-3-amino-2,5-dioxopyrrolidine-3-carboxylate (2), the chiral intermediate for the manufacture of AS-3201 (1), is described. A practical and scalable Shibasaki asymmetric amination that generates the chiral quaternary center was developed and demonstrated on kilogram scale. A safe, convenient, and large-scale hydrogenation of the hydrazine intermediate was also developed.
ALKYLIMINOMALONIC ACID AND 2-ALKYLOXAZIRIDINE-3,3-DICARBOXYLIC ACID ESTERS
Prosyanik, A.V.,Moskalenko, A.S.,Moretti, J.,Forni, A.,Torre, G.,Kostyanovskii, R.G.
, p. 431 - 437 (1986)
2-Alkyloxaziridine-3,3-dicarboxylic acid esters have been obtained by oxidizing alkylaminomalonic acid ester by monoperphtalic acid.The activation parameters for the inversion of the nitrogen atom have been obtained for a number of alkyliminomalonic acid and 2-alkyloxaziridine-3,3-dicarboxylic acid ester.
Stereoselective formation of quaternary stereogenic centers via alkylation of α-substituted malonate-imidazolidinones
Bixa, Thobela,Hunter, Roger,Andrijevic, Ana,Petersen, Wade,Su, Hong,Dhoro, Francis
, p. 762 - 769 (2015)
A new stereoselective alkylation methodology is presented for formation of chiral, nonracemic quaternary centers via a chiral auxiliary protocol involving α-alkylated malonate imidazolidinones. Based on two X-ray structures of quaternized products, the diastereoselectivity observed may be rationalized via a transition-state involving an s-transC-N conformation of the C-N bond of the auxiliary, with the metal cation (K+) chelated into the malonate six-membered hole as a Z-enolate. A deprotection protocol involving ethanethiolate exchange of the imide to the corresponding thioester, followed by a standard Fukuyama reduction and a borohydride reduction, furnishes α,α-quaternized-hydroxypropionates in high ee overall.
Highly efficient selective monohydrolysis of dialkyl malonates and their derivatives
Niwayama, Satomi,Cho, Hanjoung,Lin, Chunlei
, p. 4434 - 4436 (2008)
The highly efficient selective monohydrolysis of symmetric diesters has been applied to monohydrolysis of several dialkyl malonates and their derivatives. The best conditions apply 0.8-1.2 equiv of aqueous KOH with a co-solvent, THF or acetonitrile, at 0 °C. The procedure is highly practical, yielding the corresponding half-esters in high yields in a straightforward manner, without inducing decarboxylation. It was found that the selectivity tends to become higher with increased hydrophobicity.
Synthesis of diverse N, O-bridged calix[1]arene[4]pyridine-C60 dyads and triads and formation of intramolecular self-inclusion complexes
Wu, Jin-Cheng,Wang, De-Xian,Huang, Zhi-Tang,Wang, Mei-Xiang
, p. 8604 - 8614 (2010)
Starting from both the bridging nitrogen atom-functionalized and the upper rim-functionalized N,O-bridged calix[1]arene[4]pyridine reactants, different types of heteracalixaromatics-C60 dyads and triads of varied spacers were expediently synthesized using mainly the click reaction as the key step. By means of various spectroscopic methods, the heteracalixaromatics-C60 dyads and triads obtained have been shown to form intramolecular self-inclusion complexes rather than oligomers or polymers in solution because of a flexible spacer in between the heteracalixaromatic ring and C60 moiety. The current study, coupled with previous investigations, would provide the guideline for the construction of supramolecular fullerene motifs based on molecular design of the dyads and triads.
Practical large scale synthesis of half-esters of malonic acid
Niwayama, Satomi,Cho, Hanjoung
, p. 508 - 510 (2009)
A practical large-scale synthesis of monomethyl malonate and monoethyl malonate, which are among the most commonly applied half-esters in organic synthesis, is described, applying the highly efficient selective monohydrolysis of symmetric diesters we reported before. The optimal conditions with regard to the type of base, equivalent, co-solvents, and the reaction time have been examined for large-scale reactions. Monomethyl malonate and monoethyl malonate were obtained in high yields with near 100% purity within only half a day. The conditions of this selective monohydrolysis reaction are environmentally benign and straightforward, as it requires only water, a small proportion of a volatile co-solvent, and inexpensive reagents, and produces no hazardous by-products, and therefore the synthetic utility of this reaction in process chemistry is expected.
Selective monoesterification of malonic acid catalyzed by boric acid
Levonis, Stephan M.,Bornaghi, Laurent F.,Houston, Todd A.
, p. 821 - 823 (2007)
Boric acid catalyzes the monoesterification of malonic acid, likely through a chelation mechanism that is not available to the monoester product. Under more forcing conditions, diesters form to some extent, but conditions can be optimized to favour the monoester product (56?80%). With the easily handled solid acid catalyst, these reactions can be run with excess alcohol as solvent or with stoichiometric amounts of alcohol in acetonitrile with moderate heating. CSIRO 2007.
Decomposition of malonic anhydrides
Perrin, Charles L.,Flach, Agnes,Manalo, Marlon N.
, p. 9698 - 9707 (2012)
Malonic anhydrides decompose at or below room temperature, to form a ketene and carbon dioxide. Rate constants for the thermal decomposition of malonic, methylmalonic, and dimethylmalonic anhydrides were measured by NMR spectroscopy at various temperatures, and activation parameters were evaluated from the temperature dependence of the rate constants. Methylmalonic anhydride is the fastest, with the lowest δH?, and dimethylmalonic anhydride is the slowest. The nonlinear dependence on the number of methyl groups is discussed in terms of a concerted [2s + (2s + 2s)] or [2s + 2a] cycloreversion that proceeds via a twisted transition-state structure, supported by computations.
Hydrogen-Bonding Assisted Catalytic Kinetic Resolution of Acyclic β-Hydroxy Amides
Porey, Arka,Mondal, Bhaskar Deb,Guin, Joyram
supporting information, p. 8786 - 8791 (2021/03/17)
Enantioenriched acyclic α-substituted β-hydroxy amides are valuable compounds in chemical, material and medicinal sciences, but their enantioselective synthesis remains challenging. A catalytic kinetic resolution (KR) of such amides with selectivity factor(s) up to >200 is developed via enantioselective acylation of primary alcohol with N-heterocyclic carbene. An enhanced selectivity for the catalytic KR process is realized using cyclic tertiary amine as base additive. Diastereomeric transition state models for the process are proposed to rationalize the origin of enantioselectivity.
