831-14-1Relevant articles and documents
Direct C-H Arylation of Aldehydes by Merging Photocatalyzed Hydrogen Atom Transfer with Palladium Catalysis
Chen, Guangying,Cheng, Gui-Juan,Guo, Bin,Li, Xiaobao,Ran, Chongzhao,Wang, Lu,Wang, Ting,Wei, Jun-Jie,Zheng, Caijuan,Zheng, Chao
, p. 7543 - 7551 (2020/08/21)
Herein, we report that merging palladium catalysis with hydrogen atom transfer (HAT) photocatalysis enabled direct arylations and alkenylations of aldehyde C-H bonds, facilitating visible light-catalyzed construction of a variety of ketones. Tetrabutylammonium decatungstate and anthraquinone were found to act as synergistic HAT photocatalysts. Density functional theory calculations suggested a Pd0-PdII-PdIII-PdI-Pd0 pathway and revealed that regeneration of the Pd0 catalyst and the photocatalyst occurs simultaneously in the presence of KHCO3. This regeneration features a low energy barrier, promoting efficient coupling of the palladium catalytic cycle with the photocatalytic cycle. The work reported herein suggests great promise for further applications of HAT photocatalysis in palladium-catalyzed cross-coupling and C-H functionalization reactions to be successful.
Iron-Catalyzed Cleavage Reaction of Keto Acids with Aliphatic Aldehydes for the Synthesis of Ketones and Ketone Esters
Zhou, Fangyuan,Li, Lesong,Lin, Kao,Zhang, Feng,Deng, Guo-Jun,Gong, Hang
supporting information, p. 4246 - 4250 (2020/03/11)
The radical–radical coupling reaction is an important synthetic strategy. In this study, the iron-catalyzed radical–radical cross-coupling reaction based on the decarboxylation of keto acids and decarbonylation of aliphatic aldehydes to obtain valuable aryl ketones is reported for the first time. Remarkably, when tertiary aldehydes were used as carbonyl sources, ketone esters were selectively obtained instead of ketones. The gram-scale preparation of aryl ketone through this strategy was easily achieved by using only 3 mol % of the iron catalyst. As a proof-of-concept, the bioactive molecule flurprimidol was synthesized in two steps by using this strategy.
Method for preparing aryl ketone based on iron-catalyzed free radical-free radical coupling reaction such as ketonic acid decarboxylation and fatty aldehyde de-carbonylation
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Paragraph 0045-0046, (2020/05/05)
The invention discloses a method for preparing an aryl ketone derivative based on a free radical-free radical cross-coupling reaction such as ketonic acid decarboxylation and fatty aldehyde de-carbonylation. The method comprises the following steps: reacting aryl-substituted ketonic acid with fatty aldehyde under the catalytic action of ferric triacetylacetonate to generate an aryl ketone derivative; the gram-grade reaction can be realized by the method only by using 3mol% of an iron catalyst; and the method has the advantages of no need of consumption of a large amount of a Lewis acid catalyst or a stoichiometric organic metal reagent, mild reaction conditions, one-step reaction, few by-products, wide substrate application range and scalable reaction, and overcomes the defects of large catalyst consumption, insufficient functional group tolerance, many by-products and the like in the prior art.
Acylation of Alkenes with the Aid of AlCl3 and 2,6-Dibromopyridine
Tanaka, Shinya,Kunisawa, Tsukasa,Yoshii, Yuji,Hattori, Tetsutaro
supporting information, p. 8509 - 8513 (2019/11/03)
Friedel-Crafts-type acylation of alkenes with acyl chlorides has been successfully conducted with a wide substrate scope by the combined use of AlCl3 and 2,6-dibromopyridine. Trisubstituted alkenes afford allylketones or vinylketones depending on the presence or absence of hydrogen atom(s) at the β-position to the acylation site, while monosubstituted alkenes exclusively afford vinylketones.
Palladium-Catalyzed Aerobic Oxidative Dehydrogenation of Cyclohexenes to Substituted Arene Derivatives
Iosub, Andrei V.,Stahl, Shannon S.
supporting information, p. 3454 - 3457 (2015/03/30)
A palladium(II) catalyst system has been identified for aerobic dehydrogenation of substituted cyclohexenes to the corresponding arene derivatives. Use of sodium anthraquinone-2-sulfonate (AMS) as a cocatalyst enhances the product yields. A wide range of functional groups are tolerated in the reactions, and the scope and limitations of the method are described. The catalytic dehydrogenation of cyclohexenes is showcased in an efficient route to a phthalimide-based TRPA1 activity modulator.
Iridium-catalyzed C-C coupling via transfer hydrogenation: Carbonyl addition from the alcohol or aldehyde oxidation level employing 1,3-cyclohexadiene
Bower, John F.,Patman, Ryan L.,Krische, Michael J.
supporting information; experimental part, p. 1033 - 1035 (2009/04/07)
Under hydrogen autotransfer conditions employing a catalyst derived from [lr(cod)CI]2 and BIPHEP, 1,3-cyclohexadiene (CHD) couples to benzylic alcohols 1a-9a to furnish carbonyl addition products 1c-9c, which appear as single diastereomers with variable quantities of regioisomeric adducts 1d-9d. Under related transfer hydrogenation conditions employing isopropanol as terminal reductant, identical carbonyl adducts 1c-9c are obtained from the aldehyde oxidation level. Isotopic labeling studies corroborate a mechanism involving hydrogen donation from the reactant alcohol or sacrificial alcohol (i-PrOH).
Oxidative Cyclization of δ,ε- and ε,ζ-Unsaturated Enol Silyl Ethers and Unsaturated Siloxycyclopropanes
Snider, Barry B.,Kwon, Taesoo
, p. 2399 - 2410 (2007/10/02)
Oxidative cyclization of δ,ε- and ε,ζ-unsaturated enol silyl ethers 4a and 4b with cupric triflate and cuprous oxide or ceric ammonium nitrate and sodium bicarbonate in acetonitrile provides the tricyclic ketones 5a and 5b stereoselectively.These cyclizat
Oxidative Cyclization of δ,ε- and ε,ζ-Unsaturated Enol Silyl Ethers
Snider, Barry B.,Kwon, Taesoo
, p. 4786 - 4788 (2007/10/02)
Oxidative cyclization of δ,ε- and ε,ζ-unsaturated enol silyl ethers of aryl ketones with cupric triflate and cuprous oxide or ceric ammonium nitrate and sodium bicarbonate in acetonitrile provides tricyclic ketones stereoselectively.
CHEMOSELECTIVITY IN MOLYBDENUM CATALYZED ALCOHOL AND ALDEHYDE OXIDATIONS
Trost, Barry M.,Masuyama, Yoshiro
, p. 173 - 176 (2007/10/02)
Hydrogen peroxide in the presence of (NH4)6Mo7O24*4H2O and potassium carbonate is a chemoselective method to oxidize secondary alcohols to ketones and to oxidize aldehydes to acids, the latter also accelerated by cerium chloride.
