7469-80-9Relevant academic research and scientific papers
From Esters to Ketones via a Photoredox-Assisted Reductive Acyl Cross-Coupling Strategy
Chen, Yukun,Li, Weirong,Luo, Yixin,Qi, Xiaotian,Xi, Xiaoxiang,Xu, Minghao,Yuan, Weiming,Zhao, Hongping,Zheng, Songlin
supporting information, (2021/12/06)
A method was developed for ketone synthesis via a photoredox-assisted reductive acyl cross-coupling (PARAC) using a nickel/photoredox dual-catalyzed cross-electrophile coupling of two different carboxylic acid esters. A variety of aryl, 1°, 2°, 3°-alkyl 2-pyridyl esters can act as acyl electrophiles while N-(acyloxy)phthalimides (NHPI esters) act as 1°, 2°, 3°-radical precursors. Our PARAC strategy provides an alternative and reliable way to synthesize various sterically congested 3°-3°, 3°-2°, and aryl-3° ketones under mild and highly unified conditions, which have been otherwise difficult to access. The combined experimental and computational studies identified a Ni0/NiI/NiIII pathway for ketone formation.
Electrochemical Fluorination of Vinyl Boronates through Donor-Stabilized Vinyl Carbocation Intermediates**
Wigman, Benjamin,Lee, Woojin,Wei, Wenjing,Houk, Kendall N.,Nelson, Hosea M.
, (2022/02/10)
The electrochemical generation of vinyl carbocations from alkenyl boronic esters and boronates is reported. Using easy-to-handle nucleophilic fluoride reagents, these intermediates are trapped to form fully substituted vinyl fluorides. Mechanistic studies support the formation of dicoordinated carbocations through sequential single-electron oxidation events. Notably, this electrochemical fluorination features fast reaction times and Lewis acid-free conditions. This transformation provides a complementary method to access vinyl fluorides with simple fluoride salts such as TBAF.
Palladium-NHC (NHC = N-heterocyclic Carbene)-Catalyzed Suzuki-Miyaura Cross-Coupling of Alkyl Amides
Wang, Chang-An,Rahman, Md. Mahbubur,Bisz, Elwira,Dziuk, B?az?ej,Szostak, Roman,Szostak, Michal
, p. 2426 - 2433 (2022/02/17)
We report the Pd-catalyzed Suzuki-Miyaura cross-coupling of aliphatic amides. Although tremendous advances have been made in the cross-coupling of aromatic amides, C-C bond formation from aliphatic amides by selective N-C(O) cleavage has remained a major challenge. This longstanding problem in Pd catalysis has been addressed herein by a combination of (1) the discovery of N,N-pym/Boc amides as a class of readily accessible amide-based reagents for cross-coupling and (2) steric tuning of well-defined Pd(II)-NHC catalysts for cross-coupling. The methodology is effective for the cross-coupling of an array of 3°, 2°, and 1° aliphatic amide derivatives. The catalyst system is user-friendly, since the catalysts are readily available and are air- and bench-stable. Mechanistic studies strongly support an amide bond twist and external nN → π*C═O/Ar delocalization as a unified enabling feature of N,N-pym/Boc amides in selective N-C(O) bond activation. The method provides a rare example of Pd-NHC-catalyzed cross-coupling of aliphatic acyl amide electrophiles.
Discovery of Novel 3-Amino-4-alkoxyphenylketones as PDE4 Inhibitors with Improved Oral Bioavailability and Safety against Spatial Memory Impairments
Feng, Kai-Wen,He, Jia-Peng,Liu, Lu,Wang, Hai-Tao,Xia, Chuang,Xu, Jiang-Ping,Zheng, Lei,Zhou, Zhong-Zhen
, p. 390 - 405 (2022/02/07)
To realize PDE4 inhibitors with good developmental potentiality for the treatment of dementia, structure-based optimizations of lead compound FCPR03 resulted in novel aminophenylketones 9c and 9H with low nanomolar potency, which displayed comparable acti
Aminophenone compounds as well as preparation method and application thereof
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Paragraph 0047; 0051-0053; 0250-0251; 0255-0257, (2021/02/06)
The invention belongs to the technical field of medicinal chemistry, and particularly relates to aminophenone compounds as well as a preparation method and application thereof. The aminophenone compounds provided by the invention have a good inhibition effect on PDE4, also have good bioavailability, can be applied to preparation of drugs for treating PDE4-related diseases, and increase the optionsof drugs for treating PDE4-related diseases; and the effect of a part of the aminophenone compounds is equivalent to the effect of positive drugs, and the aminophenone compounds have good developmentpotential.
1,3-Alkyl Transposition in Allylic Alcohols Enabled by Proton-Coupled Electron Transfer
Knowles, Robert R.,Seidler, Gesa,Zhao, Kuo
supporting information, p. 20190 - 20195 (2021/08/13)
A method is described for the isomerization of acyclic allylic alcohols into β-functionalized ketones via 1,3-alkyl transposition. This reaction proceeds via light-driven proton-coupled electron transfer (PCET) activation of the O?H bond in the allylic al
Acylboronates in polarity-reversed generation of acyl palladium(II) intermediates
Trofimova, Alina,Holownia, Aleksandra,Tien, Chieh-Hung,?irvinskas, Martynas J.,Yudin, Andrei K.
supporting information, p. 3294 - 3299 (2021/05/07)
We report a catalytic cross-coupling process between aryl (pseudo)halides and boron-based acyl anion equivalents. This mode of acylboronate reactivity represents polarity reversal, which is supported by the observation of tetracoordinated boronate and acyl palladium(II) species by 11B, 31P NMR, and mass spectrometry. A broad scope of aliphatic and aromatic acylboronates has been examined, as well as a variety of aryl (pseudo)halides.
Nickel-Mediated Photoreductive Cross Coupling of Carboxylic Acid Derivatives for Ketone Synthesis**
Brauer, Jan,Quraishi, Elisabeth,Kammer, Lisa Marie,Opatz, Till
supporting information, p. 18168 - 18174 (2021/11/30)
A simple visible light photochemical, nickel-catalyzed synthesis of ketones from carboxylic acid-derived precursors is presented. Hantzsch ester (HE) functions as a cheap, green and strong photoreductant to facilitate radical generation and also engages in the Ni-catalytic cycle to restore the reactive species. With this dual role, HE allows for the coupling of a large variety of radicals (1°,2°, benzylic, α-oxy & α-amino) with aroyl and alkanoyl moieties, a new feature in reactions of this type. With both precursors deriving from abundant carboxylic acids, this protocol is a welcome addition to the organic chemistry toolbox. The reaction proceeds under mild conditions without the need for toxic metal reagents or bases and shows a wide scope, including pharmaceuticals and complex molecular architectures.
Rapid and Direct Photocatalytic C(sp3)?H Acylation and Arylation in Flow
Bovy, Lo?c,Broersma, Rémy,Mazzarella, Daniele,No?l, Timothy,Pulcinella, Antonio
supporting information, p. 21277 - 21282 (2021/08/23)
Herein, we report a photocatalytic procedure that enables the acylation/arylation of unfunctionalized alkyl derivatives in flow. The method exploits the ability of the decatungstate anion to act as a hydrogen atom abstractor and produce nucleophilic carbon-centered radicals that are intercepted by a nickel catalyst to ultimately forge C(sp3)?C(sp2) bonds. Owing to the intensified conditions in flow, the reaction time can be reduced from 12–48 hours to only 5–15 minutes. Finally, kinetic measurements highlight how the intensified conditions do not change the reaction mechanism but reliably speed up the overall process.
C(sp3)-H Bond Acylation with N -Acyl Imides under Photoredox/ Nickel Dual Catalysis
Kerackian, Taline,Reina, Antonio,Krachko, Tetiana,Boddaert, Hugo,Bouyssi, Didier,Monteiro, Nuno,Amgoune, Abderrahmane
supporting information, p. 1531 - 1536 (2020/10/21)
A novel Ni/photoredox-catalyzed acylation of aliphatic substrates, including simple alkanes and dialkyl ethers, has been developed. The method combines C-N bond activation of amides with a radical relay mechanism involving hydrogen-atom transfer. The protocol is operationally simple, employs bench-stable N -acyl imides as acyl-transfer reagents, and permits facile access to alkyl ketones under very mild conditions.
