1196-67-4Relevant academic research and scientific papers
Deep eutectic solvent-catalyzed Meyer-Schuster rearrangement of propargylic alcohols under mild and bench reaction conditions
Ríos-Lombardía, Nicolás,Cicco, Luciana,Yamamoto, Kota,Hernández-Fernández, José A.,Morís, Francisco,Capriati, Vito,García-álvarez, Joaquín,González-Sabín, Javier
, p. 15165 - 15168 (2020)
The Meyer-Schuster rearrangement of propargylic alcohols into α,β-unsaturated carbonyl compounds has been revisited by setting up an atom-economic process catalyzed by a deep eutectic solvent FeCl3·6H2O/glycerol. Isomerizations take place smoothly, at room temperature, under air and with short reaction times. The unique solubilizing properties of the eutectic mixture enabled the use of a substrate concentration up to 1.0 M with the medium being recycled up to ten runs without any loss of catalytic activity. This journal is
A novel catalyst iron(II) tetra(1,4-dithin)porphyrazine for oxygenating degradation of organic pollutants in aqueous solutions
Deng, Kejian,Huang, Fei,Wang, Duoyuan,Peng, Zhenghe,Zhou, Yunhong
, p. 34 - 35 (2004)
An efficient catalyst of the title complex (abbreviated as FePz(dtn) 4) is a porphyrin-like complex, which is able to activate molecular oxygen for oxidative degradation of organic compounds in an extensive pH region without light excitation. The experiments indicated that the FePz(dtn) 4/O2 system showed an excellent oxygenation capability, in which the Rhodamine B(RhB) was degraded nearly 52% in alkaline aqueous solution in the seven hours and the p-nitrobenzoic acid(NBA) could be also oxygenated nearly 85% detected by UV-vis, HPLC in the similar conditions. The degradation components of RhB and NBA were analyzed by GC-MS and IR. The mineralization rate of RhB and NBA were 12 and 11.1% after reaction for 24 h respectively.
BICHROMATES DE PHOSPHONIUM: REACTIFS D'OXYDATION
Cristau, Henri-Jean,Torreilles, Eliane,Morand, Philippe,Christol, Henri
, p. 1775 - 1776 (1986)
The bisphosphonium bichromate 1, appears as particularly mild and selective for the oxidation of primary or secondary alcohols.It performs the oxidation of primary alcohols into aldehydes without further oxidation in acid and without double-bond isomerisation or migration for such alcohols as geraniol; it allows also the fully selective oxidation of benzylic or allylic alcohols versus aliphatic alcohols.
Two-carbon homologation of aldehydes and ketones to α,β- unsaturated aldehydes
Petroski, Richard J.,Vermillion, Karl,Cosse, Allard A.
, p. 5062 - 5078 (2011)
Phosphonate reagents were developed for the two-carbon homologation of aldehydes or ketones to unbranched- or methyl-branched α,β- unsaturated aldehydes. The phosphonate reagents, diethyl methylformyl-2- phosphonate dimethylhydrazone and diethyl ethylformyl-2-phosphonate dimethylhydrazone, contained a protected aldehyde group instead of the usual ester group. A homologation cycle entailed condensation of the reagent with the starting aldehyde, followed by removal of the dimethylhydrazone protective group with a biphasic mixture of 1 M HCl and petroleum ether. This robust two-step process worked with a variety of aldehydes and ketones. Overall isolated yields of unsaturated aldehyde products ranged from 71% to 86% after the condensation and deprotection steps.
Synthetic approaches to mono- and bicyclic perortho-esters with a central 1,2,4-trioxane ring as the privileged lead structure in antimalarial and antitumor-active peroxides and clarification of the peroxide relevance
Griesbeck, Axel G.,Br?utigam, Maria,Kleczka, Margarethe,Raabe, Angela
, (2017)
The synthesis of 4-styryl-substituted 2,3,8-trioxabicyclo[3.3.1]nonanes, peroxides with the core structure of the bioactive 1,2,4-trioxane ring, was conducted by a multistep route starting from the aryl methyl ketones 1a-1c. Condensation and reduction/oxidation delivered enals 4a-4c that were coupled with ethyl acetate and reduced to the 1,3-diol substrates 6a-6c. Highly diastereoselective photooxygenation delivered the hydroperoxides 7a-7c and subsequent PPTS (pyridinium-p-toluenesulfonic acid)-catalyzed peroxyacetalization with alkyl triorthoacetates gave the cyclic peroxides 8a-8e. These compounds in general show only moderate antimalarial activities. In order to extend the repertoire of cyclic peroxide structure, we aimed for the synthesis of spiro-perorthocarbonates from orthoester condensation of β-hydroxy hydroperoxide 9 but could only realize the monocyclic perorthocarbonate 10. That the central peroxide moiety is the key structural motif in anticancer active GST (glutathione S-transferase)-inhibitors was elucidated by the synthesis of a 1,3-dioxane 15-with a similar substitution pattern as the pharmacologically active peroxide 11-via a singlet oxygen ene route from the homoallylic alcohol 12.
Stereodefined rhodium-catalysed 1,4-H/D delivery for modular syntheses and deuterium integration
Cheng, Bao,Fang, Huayi,Ma, Shengming,Qian, Hui,Wang, Weiyi,Yu, Yibo,Zhang, Xue
, p. 586 - 594 (2021/07/17)
Deuterium-incorporated compounds are of high interest owing to their importance in the pharmaceutical industry, organic synthesis and materials science. So far, the integration of deuterium into the inert, saturated magic methyl or methylene groups of covalent molecules remains challenging. Here, we present a 1,4-H delivery of allylic metallic species to provide a highly stereoselective and straightforward approach to 3-methyl-2(E)-enals or -enones from readily available 2,3-allenols and organoboronic acids. The reaction accommodates many synthetically versatile functional groups as well as multi-pharmacophores, and is not limited to the formation of 3-methyl derivatives. By applying 1,4-H or D delivery, deuterium atom(s) from differently deuterated allenols can be edited into the methyl or methylene groups of versatile organic skeletons, resulting in the efficient formation of 4-monodeuterated, 1,4- and 4,4-doubly deuterated, and 4,4,4-triply deuterated 2(E)-enals or -enones. These powerful platform molecules can provide straightforward paths to other deuterated compounds for different purposes. [Figure not available: see fulltext.].
Sulfur-controlled and rhodium-catalyzed formal (3 + 3) transannulation of thioacyl carbenes with alk-2-enals and mechanistic insights
Wu, Qiuyue,Dong, Ziyang,Xu, Jiaxi,Yang, Zhanhui
, p. 3173 - 3180 (2021/04/21)
A rhodium-catalyzed denitrogenative formal (3 + 3) transannulation of 1,2,3-thiadiazoles with alk-2-enals is achieved, producing 2,3-dihydrothiopyran-4-ones in moderate to excellent yields. An inverse KIE of 0.49 is obtained, suggesting the reversibility of the oxidative addition of thioacyl Rh(i) carbenes to alk-2-enals. The late-stage structural modifications of steroid compounds are realized. Moreover, our studies show that thioacyl carbenes have different reactivities to those of α-oxo and α-imino carbenes, and highlight the importance of heteroatoms in deciding the reactivities of heterovinyl carbenes.
Saegusa Oxidation of Enol Ethers at Extremely Low Pd-Catalyst Loadings under Ligand-free and Aqueous Conditions: Insight into the Pd(II)/Cu(II)-Catalyst System
Zhu, Quan,Luo, Yunsong,Guo, Yongyan,Zhang, Yushun,Tao, Yunhai
, p. 5463 - 5476 (2021/05/05)
A highly efficient and practical Pd(II)/Cu(OAc)2-catalyst system of Saegusa oxidation, which converts enol ethers to the corresponding enals with a number of diverse substrates at extremely low catalyst loadings (500 mol ppm) under ligand-free and aqueous conditions, is described. Its synthetic utility was demonstrated by large-scale applications of the catalyst system to important nature molecules. This work allows Saegusa oxidation to become a highly practical approach to preparing enals and also suggests new insight into the Pd(II)/Cu(II)-catalyst system for dehydrogenation of carbonyl compounds and decreasing Pd-catalyst loadings.
Method for preparing olefine aldehyde through catalytic oxidation of enol ether
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Paragraph 0082-0086; 0088, (2021/06/23)
The invention relates to the technical field of olefine aldehyde preparation, and provides a method for preparing olefine aldehyde through catalytic oxidation of enol ether. According to the invention, a palladium catalyst, a copper salt, a solvent and enol ether are mixed and subjected to a catalytic oxidation reaction to obtain olefine aldehyde. According to the method, the copper salt is used as the oxidizing agent, the mixed solvent of water and acetonitrile is used as the reaction solvent, and the volume ratio of water to acetonitrile in the mixed solvent is controlled to be (3-7): (3-7), so that the catalytic oxidation reaction can be smoothly carried out in the mixed solvent with a specific ratio, and the generation of palladium black precipitate can be avoided. The method provided by the invention has the advantages of simple steps, low reagent cost, no need of dangerous reagents, wide substrate adaptability and small catalyst dosage. Furthermore, octadecane mercaptan is added to promote the catalytic oxidation reaction, and when the dosage of the palladium catalyst is extremely low, the olefine aldehyde yield can be greatly increased by adding octadecane mercaptan.
Direct Synthesis of Enones by Visible-Light-Promoted Oxygenation of Trisubstituted Olefins Using Molecular Oxygen
Harada, Shinji,Matsuda, Daiki,Morikawa, Takahiro,Nishida, Atsushi
supporting information, p. 1372 - 1377 (2020/10/02)
A one-step synthesis of enones from olefins is described. The reaction was performed under visible-light irradiation in the presence of molecular oxygen and a photocatalyst. The reaction proceeded with various types of trisubstituted olefins to give enones in good yields with high regioselectivity. In particular, oxygen- and nitrogen-containing functional groups, heteroaromatic rings, and cyclopropanes were tolerated. Mechanistic studies and previous reports indicated that the active oxygen species generated in the reaction system is singlet oxygen.
