1072-21-5Relevant articles and documents
Oxidation by Cobalt(III) Acetate. Part 4. Kinetics and Mechanism of the Oxidation of Glycols in Acetic Acid
Morimoto, Takashi,Hirano, Masao
, p. 1087 - 1090 (1982)
The oxidative cleavage of 1,2-glycols by cobalt(III) acetate in acetic acid was studied kinetically in order to clarify the reaction mechanism.The rates were first-order in both cobalt(III) acetate and substrate for the oxidation of all the diols used. cis-Cyclopentane-1,2-diol and decalin-9,10-diol were more rapidly oxidized than the corresponding trans-isomers, respectively, whereas cis-cyclohexane-1,2-diol was more slowly oxidized than the trans-isomer.The oxidation of trans-2-methoxycyclohexanol was much slower than that of the corresponding diol.The mechanism involving the formation of a bidentate complex between cobalt(III) acetate dimer and glycol is discussed.
Catalytic aerobic oxidation of diols under photo-irradiation: Highly efficient synthesis of lactols
Miyata, Atsushi,Furukawa, Mizuki,Irie, Ryo,Katsuki, Tsutomu
, p. 3481 - 3484 (2002)
Aerobic oxidation of 1, n- and 1,ω-diols with (ON)Ru(salen) 1 as the catalyst was found to give the corresponding lactols in almost quantitative yields. Furthermore, in the oxidation of 2,2-dimethylalkane-1,ω-diols, less sterically hindered ω-alcohols were found to be preferentially oxidized when (ON)Ru(salen) 6 was used as the catalyst. n-Decanol was preferentially oxidized in the presence of 2,2-dimethylpropanol also by using 6 as the catalyst.
Asymmetric syntheses of the N-terminal α-hydroxy-β-amino acid components of microginins 612, 646 and 680
Davies, Stephen G.,Fletcher, Ai M.,Hanby, Abigail R.,Roberts, Paul M.,Thomson, James E.
, p. 1756 - 1764 (2017)
The asymmetric syntheses of the N-terminal α-hydroxy-β-amino acid components of microginins 612, 646 and 680 are reported. Conjugate addition of lithium (R)-N-benzyl-N-(α-methylbenzyl)amide to the requisite (E)-α,β-unsaturated ester followed by in situ enolate oxidation with (?)-(camphorsulfonyl)oxaziridne (CSO) gave the corresponding anti-α-hydroxy-β-amino esters. Sequential Swern oxidation followed by diastereoselective reduction gave the corresponding syn-α-hydroxy-β-amino esters. Subsequent N-debenzylation (i.e., hydrogenolysis for microginin 612, and NaBrO3-mediated oxidative N-debenzylation for microginins 646 and 680) followed by acid catalysed ester hydrolysis gave the corresponding syn-α-hydroxy-β-amino acids, the N-terminal components of microginins 612, 646 and 680, in good yield. An analogous strategy for elaboration of the enantiopure anti-α-hydroxy-β-amino esters facilitated the asymmetric synthesis of the corresponding C(2)-epimeric α-hydroxy-β-amino acids.
-
Hintz,Johnson
, p. 556,558 (1967)
-
Formation of Dicarbonyl Compounds in the Flash Vacuum Pyrolysis of Saturated Bicyclic Peroxides
Bloodworth, A. J.,Baker, David S.,Eggelte, Henny J.
, p. 1034 - 1036 (1982)
Under flash vacuum pyrolysis, dioxabicycloalkanes (n = 3,4, and 5) isomerise to keto-aldehydes, MeCOnCHO, whereas dioxabicycloalkanes (n = 2,3, and 4) fragment to give, by loss of hydrogen and ethylene, mixtures of cycloalkane-1,4-diones and dialdehydes, OHCnCHO.
Efficient and Facile Glycol Cleavage Oxidation Using Improved Silica Gel-Supportes Sodium Metaperiodate
Zhong, Yong-Li,Shing, Tony K. M.
, p. 2622 - 2624 (1997)
-
Production of Hydroxy Acids: Selective Double Oxidation of Diols by Flavoprotein Alcohol Oxidase
Fraaije, Marco W.,Martin, Caterina,Trajkovic, Milos
, p. 4869 - 4872 (2020)
Flavoprotein oxidases can catalyze oxidations of alcohols and amines by merely using molecular oxygen as the oxidant, making this class of enzymes appealing for biocatalysis. The FAD-containing (FAD=flavin adenine dinucleotide) alcohol oxidase from P. chrysosporium facilitated double and triple oxidations for a range of aliphatic diols. Interestingly, depending on the diol substrate, these reactions result in formation of either lactones or hydroxy acids. For example, diethylene glycol could be selectively and fully converted into 2-(2-hydroxyethoxy)acetic acid. Such a facile cofactor-independent biocatalytic route towards hydroxy acids opens up new avenues for the preparation of polyester building blocks.
De Vries,Schors
, p. 5689 (1968)
C-C bond cleavage of cyclohexene oxide in the reaction with 1- aminoindoline
Kiryu, Yoshimitu,Itoh, Satoshi,Kaneko, Kimiyoshi,Katayama, Hajime
, p. 1810 - 1813 (1998)
The reaction of cyclohexene oxide with 1-aminoindoline under neat conditions gave a C-C bond-cleavage product of cyclohexene oxide as a dihydrazone and a 1,2-aminoalcohol-type product. No hydrazinoalcohol was obtained.
Syntheses of bifunctional compounds from cycloalkenes via ozonide intermediates
Hon, Yung-Son,Yan, Jiann-Long
, p. 5217 - 5232 (1997)
The ozonolytic cleavage of cycloalkene in the presence of methyl pyruvate affords a tri-substituted ozonide. The resulted tri-substituted ozonide moiety contained three reactive centers (i.e, peroxide, ozonide ring proton and methoxycarbonyl group) which could be transformed to different functional groups under different conditions in good yields. It is a very efficient and versatile methodology to prepare the terminal differentiated compounds from symmetric cycloalkenes in two steps in high yields.
Graft copolymers with polyamide backbones via combination of passerini multicomponent polymerization and controlled chain-growth polymerization
Deng, Xin-Xing,Cui, Yang,Wang, Yao-Zong,Du, Fu-Sheng,Li, Zi-Chen
, p. 555 - 561 (2014)
We report a facile 'grafting from' approach to graft copolymers with polyamide backbones and controlled vinyl polymer or polyester side chains. Two polyamides with in situ-formed pendant bromide or hydroxyl groups were obtained by Passerini-based multicomponent polymerization. They were used respectively to initiate the atom-transfer radical polymerization of vinyl monomers or the ring-opening polymerization of lactones to generate two new types of graft copolymers. One of the important features of the method is that the pendant initiators are generated in situ from non-branching monomers, and they are linked to the polymer backbone by ester bonds. Therefore, the vinyl polymer side chains could be detached from the backbones, and their structures could thus be fully characterized. Moreover, multicomponent polymerization and atom-transfer radical polymerization can even be carried out in a one-pot manner. CSIRO 2014.
Products of the gas-phase reaction of OH radicals with cyclohexane: Reactions of the cyclohexoxy radical
Aschmann, Sara M.,Chew, Andrew A.,Arey, Janet,Atkinson, Roger
, p. 8042 - 8048 (1997)
Products of the gas-phase reactions of OH radicals with cyclohexane and cyclohexane-d12 in the presence of NO have been investigated using gas chromatography with flame ionization detection, combined gas chromatography-mass spectrometry, and in situ direct air-sampling atmospheric pressure ionization tandem mass spectrometry (API-MS). Cyclohexanone and cyclohexyl nitrate (and their deuterated analogues) were identified and quantified, with formation yields of cyclohexanone and cyclohexyl nitrate from the cyclohexane reaction of 0.321 ± 0.035 and 0.165 ± 0.021, respectively, and with cyclohexanone-d10 and cyclohexyl nitrate-d11 formation yields from the cyclohexane-d12 reaction of 0.156 ± 0.017 and 0.210 ± 0.025, respectively. The remaining products must arise from the decomposition and/or isomerization reactions of the intermediate cyclohexoxy radical. API-MS analyses of the cyclohexane and cyclohexane-d12 reactions showed the formation of cyclohexanone and cyclohexyl nitrate (and their deuterated analogues), together with ion peaks attributed to HC(O)CH2CH2CH2CH2CH 2ONO2 (formed from NO addition to the HC(O)CH2CH2CH2CH2CH 2OO? radical formed after decomposition of the cyclohexoxy radical) and HC(O)CH2CH(OH)CH2CH2CHO (formed after isomerization of the HC(O)CH2CH2CH2CH2CH 2O? radical). No evidence for isomerization of the cyclohexoxy radical was obtained from the API-MS analyses. The reactions of the cyclohexoxy radical are discussed and the data extended to the reactions of the cyclopentoxy and cycloheptoxy radicals formed from cyclopentane and cycloheptane.
Oxidation of terminal diols using an oxoammonium salt: A systematic study
Miller, Shelli A.,Bobbitt, James M.,Leadbeater, Nicholas E.
, p. 2817 - 2822 (2017)
A systematic study of the oxidation of a range of terminal diols is reported, employing the oxoammonium salt 4-acetamido-2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (4-NHAc-TEMPO+ BF4-) as the oxidant. For substrates bearing a hydrocarbon chain of seven carbon atoms or more, the sole product is the dialdehyde. A series of post-oxidation reactions have been performed showing that the product mixture resulting from the oxidation step can be taken on directly to a subsequent transformation. For diols containing four to six carbon atoms, the lactone product is the major product upon oxidation. In the case of 1,2-ethanediol and 1,3-propanediol, when using a 1 : 0.5 stoichiometric ratio of substrate to oxidant, the corresponding monoaldehyde is formed which reacts rapidly with further diol to yield the acetal product. This is of particular synthetic value given both the difficulty of their preparation using other approaches and also their potential application in further reaction chemistry.
First stereoselective syntheses of (-)-siphonodiol and (-)- tetrahydrosiphonodiol, bioactive polyacetylenes from marine sponges
Lopez, Susana,Fernandez-Trillo, Francisco,Midon, Pilar,Castedo, Luis,Saa, Carlos
, p. 6346 - 6352 (2005)
The first stereoselective total syntheses of the bioactive marine polyacetylenes (-)-siphonodiol and (-)-tetrahydrosiphonodiol were achieved using highly convergent approaches based on optimized Cadiot-Chodkiewicz and sequential Sonogashira cross-coupling reactions.
-
Greenspan,Woodburn
, p. 6345,6347 (1954)
-
-
Rigby
, p. 1907,1911 (1950)
-
IBX amides: A new family of hypervalent iodine reagents
Zhdankin, Viktor V.,Koposov, Alexey Y.,Netzel, Brian C.,Yashin, Nikolai V.,Rempel, Brian P.,Ferguson, Michael J.,Tykwinski, Rik R.
, p. 2194 - 2196 (2003)
Amides of 2-iodoxybenzoic acid (IBX amides, 1) are a new class of pentavalent iodine compounds with a pseudo-benziodoxole structure. These 2-iodoxybenzamides are useful reagents for the oxidation of alcohols, with a reactivity pattern similar to IBX (R=CH(CH3)CO2CH3 or CH(CH2Ph)CO2CH3 (in crystal structure shown)).
The ozonolytic cleavage of cycloalkenes in the presence of methyl pyruvate to yield the terminally differentiated compounds
Hon, Yung-Son,Yanb, Sann-Long
, p. 6591 - 6594 (1993)
The ozonolytic cleavage of cycloalkenes in the presence of methyl pyruvate affords the trisubstituted ozonides. These ozonides possess triple reactive sites which could be converted to several terminally differentiated products via reduction or base treatment.
-
Berkowitz,Rylander
, p. 6682 (1958)
-
Butadiene hydroformylation to adipaldehyde with Rh-based catalysts: Insights into ligand effects
Yu, Si-min,Snavely, William K.,Chaudhari, Raghunath V.,Subramaniam, Bala
, (2020)
Rh-catalyzed hydroformylation of butadiene to adipaldehyde is a promising alternative route for producing valuable C6 compounds such as adipic acid and hexamethylenediamine. Fundamental insights into reaction pathways, aimed at enhancing adipaldehyde yield, were obtained from temporal concentration profiles and in situ ReactIR studies of butadiene hydroformylation on Rh complexes at 80 °C and 14 bar syngas (molar CO/H2 = 1) pressure in a batch reactor. Specifically, the effects of operating conditions and eight commercially available ligands on activity and selectivity were systematically investigated. It was found that the adipaldehyde selectivity is independent of the ligand/Rh ratio, rhodium concentration, butadiene concentration and syngas pressure, but significantly dependent on the type of ligand used. For example, while the DIOP ligand provided an adipaldehyde yield of ～40% with butadiene as a substrate, the 6-DPPon ligand gave a maximum adipaldehyde yield of ～93% with 4-pentenal as substrate. Furthermore, the adipaldehyde selectivity correlates well with the natural bite angle of the various ligands. ReactIR studies suggest that the preferential formation of the stable rhodium η3-crotyl complex with the various Rh complexes may be the main reason for the low adipaldehyde selectivity.
Synthesis of Adipic Aldehyde by n-Selective Hydroformylation of 4-Pentenal
Mormul, Jaroslaw,Mulzer, Michael,Rosendahl, Tobias,Rominger, Frank,Limbach, Michael,Hofmann, Peter
, p. 4102 - 4108 (2015)
Several phosphine and phosphite ligands were tested in the hydroformylation of 4-pentenal to adipic aldehyde, a versatile starting material for industrially very relevant compounds. By varying the ligand structure we were able to increase the selectivity toward adipic aldehyde to >95%. Additionally, two molecular structures of important catalytic intermediates [(bisphosphite)RhH(CO)2] and one structure of a previously unknown catalyst decomposition product were obtained. (Chemical Equation Presented).
Evidence for isomerizing hydroformylation of butadiene. A combined experimental and computational study
Maji, Tapan,Mendis, Camina H.,Thompson, Ward H.,Tunge, Jon A.
, p. 145 - 152 (2016)
The (DIOP)rhodium-catalyzed hydroformylation of butadiene has been shown to give among the highest selectivities for formation of adipaldehyde, which is useful for the synthesis of nylon. Herein, isomerizing hydroformylation is shown to be a mechanism that is partially responsible for this selectivity and density functional theory studies are used to reveal the detailed pathway for the requisite alkene isomerization.
-
Dobson,N.A. et al.
, p. 16 - 24 (1961)
-
-
Pappo et al.
, p. 478 (1956)
-
Understanding the mechanism of N coordination on framework Ti of Ti-BEA zeolite and its promoting effect on alkene epoxidation reaction
Liang, Xiaohang,Liu, Dan,Luo, Yibin,Peng, Xinxin,Shu, Xingtian,Xia, Changjiu
, (2021)
The function of ammonium salts on the epoxidation performance over Ti-BEA zeolite was investigated in detail. Experiments of alkene epoxidation, side reactions of epoxide and decomposition of H2O2 with or without ammonium salts were designed, and the UV-Vis spectroscopy was employed to analyze the structure of Ti-hydroperoxo species. It is revealed that the ammonia (or amines) dissociated from the ammonium salt would chelate with the linear Ti-η1(OOH) species and form a bridged Ti-η2(OOH)-R species, which is more stable, more weaker in epoxide adsorption and acidity as well. Therefore, side reactions and H2O2 decomposition would be suppressed, and both alkene conversion and epoxide selectivity would be promoted simultaneously. On the other hand, the excessive NH3?H2O (NH3/Ti>1) or NaOH bond with the Ti-η2(OOH)-R species and generate salt-like Ti-η2(OO)-M+ species, resulting in the deactivation of Ti active center. While for ammonium salts, e.g. NH4Cl, the limited dissociation degree along with the acidic environment help the Ti active center to maintain in highly active. In short, this work provides a practical Ti active center tuning method for Ti-BEA zeolite, as well as a thorough understanding of its Ti-hydroperoxo species.
Industrial preparation method of hexamethylenediamine
-
Paragraph 0029-0030; 0033-0034; 0037-0038; 0041-0043, (2021/06/13)
The invention discloses an industrial preparation method of hexamethylenediamine, wherein the industrial preparation method comprises the following steps: 1) dissolving cyclohexene in a first organic solvent, carrying out electrocatalytic oxidation reaction in a reaction kettle, carrying out constant potential electrolysis to obtain a reaction solution, and carrying out reduced pressure distillation to obtain adipic dialdehyde; and 2) dissolving adipic dialdehyde in a second organic solvent, introducing ammonia gas and hydrogen, and carrying out reductive amination reaction under the action of a supported nickel catalyst to obtain the hexamethylenediamine. The reaction adopts an electrocatalytic oxidation mode, and the selectivity is controlled by utilizing electrode potential, so that the reaction is more accurate and sufficient, the product conversion rate is improved, and the product is easy to separate, clean and environment-friendly; according to the method, hexamethylenediamine can be prepared through rectification operation, the product conversion rate of the method reaches 98.70%, the total yield reaches 98.02%, the purity reaches 95.14%-98.13%, the requirements of industrial production are met, and the method has good application prospects in industry; in addition, raw materials and auxiliary materials are simple and easy to obtain, the price is low, the input cost is low, and the construction scale is not limited.
Phosphine ligand for butadiene hydroformylation reaction and preparation method thereof
-
Paragraph 0124-0127, (2021/06/23)
The invention discloses a bidentate phosphine ligand compound with a structure as shown in a general formula 1, a synthesis method of the bidentate phosphine ligand compound, and application of the phosphine ligand to promotion of metal catalysis of 1, 3-butadiene hydroformylation reaction.
