626-98-2Relevant academic research and scientific papers
Direct and Selective Synthesis of Adipic and Other Dicarboxylic Acids by Palladium-Catalyzed Carbonylation of Allylic Alcohols
Beller, Matthias,Ge, Yao,Huang, Weiheng,Jackstell, Ralf,Liu, Jiawang,Neumann, Helfried,Yang, Ji
supporting information, p. 20394 - 20398 (2020/09/21)
A general and direct synthesis of dicarboxylic acids including industrially important adipic acid by palladium-catalyzed dicarbonylation of allylic alcohol is reported. Specifically, the combination of PdCl2 and a bisphosphine ligand (HeMaRaphos) promotes two different carbonylation reactions with high activity and excellent selectivity.
Regioselective Isomerization of Terminal Alkenes Catalyzed by a PC(sp3)Pincer Complex with a Hemilabile Pendant Arm
De-Botton, Sophie,Filippov, D.Sc. Oleg A.,Shubina, Elena S.,Belkova, Natalia V.,Gelman, Dmitri
, p. 5959 - 5965 (2020/10/15)
We describe an efficient protocol for the regioselective isomerization of terminal alkenes employing a previously described bifunctional Ir-based PC(sp3)complex (4) possessing a hemilabile sidearm. The isomerization, catalyzed by 4, results in a one-step shift of the double bond in good to excellent selectivity, and good yield. Our mechanistic studies revealed that the reaction is driven by the stepwise migratory insertion of Ir?H species into the terminal double bond/β-H elimination events. However, the selectivity of the reaction is controlled by dissociation of the hemilabile sidearm, which acts as a selector, favoring less sterically hindered substrates such as terminal alkenes; importantly, it prevents recombination and further isomerization of the internal ones.
A PROCESS TO PRODUCE A DIENE FROM A LACTONE
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Page/Page column 27; 28, (2013/10/21)
The invention provides a process for the production of a diene. In the process, a lactone is heated in the presence of a first catalyst system to produce an alkene and carbon dioxide and the alkene is contacted with a second catalyst system to produce an alkyldiene.
Catalytic Conversion of Cellulose to Liquid Hydrocarbon Fuels by Progressive Removal of Oxygen to Facilitate Separation Processes and Achieve High Selectivities
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Page/Page column 10-11, (2010/12/31)
Described is a method to make liquid chemicals, such as functional intermediates, solvents, and liquid fuels from biomass-derived cellulose. The method is cascading; the product stream from an upstream reaction can be used as the feedstock in the next downstream reaction. The method includes the steps of deconstructing cellulose to yield a product mixture comprising levulinic acid and formic acid, converting the levulinic acid to γ-valerolactone, and converting the γ-valerolactone to pentanoic acid. Alternatively, the γ-valerolactone can be converted to a mixture of n-butenes. The pentanoic acid so formed can be further reacted to yield a host of valuable products. For example, the pentanoic acid can be decarboxylated yield 1-butene or ketonized to yield 5-nonanone. The 5-nonanone can be hydrodeoxygenated to yield nonane, or 5-nonanone can be reduced to yield 5-nonanol. The 5-nonanol can be dehydrated to yield nonene, which can be dimerized to yield a mixture of C9 and C18 olefins, which can be hydrogenated to yield a mixture of alkanes. Alternatively, the nonene may be isomerized to yield a mixture of branched olefins, which can be hydrogenated to yield a mixture of branched alkanes. The mixture of n-butenes formed from γ-valerolactone can also be subjected to isomerization and oligomerization to yield olefins in the gasoline, jet and Diesel fuel ranges.
Method for regio- and stereoselective synthesis of (E)-Β,γ- unsaturated acids from aldehydes under solvent-free conditions
Zhang, Shi-Jie,Hu, Wei-Xiao
experimental part, p. 3093 - 3100 (2010/12/19)
Synthesis of (E)-β,-γunsaturated acids from aldehydes with malonic acid has been explored under solvent-free conditions. The modified Knoevenagel condensation reaction with N-methyl morpholine (NMM) as catalyst exhibits highly β,-γ regioselectivity and exclusively E-stereoselectivity. A mechanism accounting for both regio- and stereoselectivity has been proposed and preliminarily studied. Copyright Taylor & Francis Group, LLC.
New reactions of anticancer-platinum complexes and their intriguing behaviour under various experimental conditions
Aleman, Jose,Del Solar, Virginia,Cubo, Leticia,Quiroga, Adoracion G.,Navarro Ranninger, Carmen
scheme or table, p. 10601 - 10607 (2011/01/05)
The anticancer platinum complexes here described react with organic substrates (such as acids, alkenes, alkynes) and catalyze transformations that can occur in biomolecules which contain unsaturated functions. We have analyzed the role of the platinum complexes in the observed reactions and studied the progress of the detected transformations upon variation of the reaction conditions. The Royal Society of Chemistry 2010.
PROCESS FOR THE CARBONYLATION OF A CONJUGATED DIENE
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Page 42-44, (2010/02/09)
A process for the carbonylation of a conjugated diene, comprising reacting the conjugated diene with carbon monoxide and a co-reactant having a mobile hydrogen atom in the presence of a catalyst system including: (a) a source of palladium; and (b) a bidentate diphosphine ligand of formula (II): R1R2 > p1R3m-R-R4n-p2 5R6 wherein p1 and p2 represent phosphorus atoms; R1, R2, R5, and R6 independently represent the same or different optionally substituted organic radical containing a tertiary carbon atom through which each radical is linked to the phosphorus atom; R3 and R4 independently represent the same or different optionally substituted methylene groups; R represents an organic group comprising the bivalent bridging group C1-C2 through which R is connected to R3 and R4; m and n independently represent a natural number in the range of from 0 to 4, wherein the rotation about the bond between the carbon atoms C1 and C2 of the bridging group is restricted a temperature in the range of from 0 °C to 250 °C, and wherein the dihedral angle between the plane occupied by the three atom sequence composed of C1, C2 and the atom directly bonded to C1 in the direction of p1, and the plane occupied by the three atom sequence C1, C2 and the atom directly bonded to C2 in the direction of p2, is in the range of from 0 to 120°; and (c) a source of an anion.
ALPHA-MERCAPTOACRYLIC ACID DERIVATIVES HAVING CALPAIN INHIBITORY ACTIVITY
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, (2008/06/13)
The invention covers a novel series of α-mercaptoacrylic acid derivatives that inhibit both calpain I and calpain II with a high affinity and selectivity. The compounds are useful in the treatment of neurodegenerative disorders including cerebrovascular disorders, brain injury, spinal cord, and peripheral nerve injury, cardiac infarction, cataracts, inflammation, restenosis, muscular dystrophy, and platelet aggregation. Pharmaceutical compositions, methods of using processes for preparing and novel intermediates useful in the processes are also disclosed.
4-substituted azetidinones as precursors to 2-substituted-3-carboxy carbapenem antibiotics and a method of producing them
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, (2008/06/13)
New 4-substituted azetidinones having the formulea I and II: STR1 with R1, R2, R3, R4, R5 and X defined hereafter, which are intermediates for the preparation of carbapenem and carbacephem antibacterials and processes for producing such antibacterials through the utilization of an acid mediated ring closure reaction.
STADIES ON THE WITTIG REACTION (VIII). STEREOSELECTIVITY OF DIPHENYL ALLYLIC PHOSPHONIUM YLIDS IN WITTIG REACTION
Wenfang, Huang,Jun, Zhu,Wenjing, Xiao,Yanneng, Deng
, p. 99 - 104 (2007/10/02)
Ylids generated from diphenyl allylic phosphonium salts reacted with aliphatic aldehydes containing a terminal oxygen functionized group in the absence of lithium salt to give E,E-conjugated dienes.The stereoselectivity depends mainly on the base used, the allylic part of phosphonium salts also shows some effect on stereochemistry.Eight conjugated dienic insect sex pheromones and related analogues with different E-selectivities were obtained.
