- Construction of a novel asymmetric imidazole-cored AIE probe for ratiometric imaging of endogenous leucine aminopeptidase
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We report a rational strategy to deliberately construct the first asymmetric tetraarylimidazole-based AIE probe, integrating AIE behavior in synergy with ESIPT character to image endogenous LAP for the first time. It offered good sensitivity and selectivity, and concomitantly, was applied successfully for real-time tracking of LAP in the cisplatin-induced liver injury zebrafish model.
- Feng, Bin,Hu, Yibo,Huang, Shuai,Huang, Xueyan,Lei, Qian,Zeng, Hongliang,Zeng, Qinghai,Zeng, Wenbin
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- Ascorbic Acid Promoted Oxidative Arylation of Vinyl Arenes to 2-Aryl Acetophenones without Irradiation at Room Temperature under Aerobic Conditions
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A convenient and general protocol for oxidative arylation of vinyl arenes by aryl radicals generated in situ from arene diazonium fluoroborates promoted by ascorbic acid in air at room temperature has been developed in the absence of any additive and visible light irradiation. A series of diversely substituted 2-aryl acetophenones have been obtained in good yields by this procedure.
- Majhi, Biju,Kundu, Debasish,Ranu, Brindaban C.
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- Induced osteoblast differentiation by amide derivatives of stilbene: The possible osteogenic agents
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A series of amide derivatives of stilbene was synthesized and investigated for osteogenic activity. Out of sixteen, seven compounds viz 19c, 19g, 19i, 24b, 25a, 25c and 26a showed significant osteoblast differentiation within 1 pM–1 μM concentrations. Amongst all, 26a was identified as most active molecule which presented effective mineralization of osteoblasts and expression of mRNA of osteogenic marker gene such as BMP-2, ALP, and Runx-2 at 1 pM. In estrogen-deficient balb/c mice, 26a showed significant osteogenic activity at 5 mg-kg?1 body weight dose. The protein expression study for estrogen receptors α and β (ER-α & ER-β) using mouse calvarial osteoblasts (MCOs) and molecular docking analyses showed preferential expression of ER-β by 26a indicating the possibility of ER-β mediated osteogenic activity of 26a.
- Bawankule, Dnyaneshwar U.,Gupta, Atul,Imran Ahamad, Mohd.,John, Aijaz A,Khan, Feroz,Luqman, Suaib,Prakash, Ravi,Singh, Divya,Wani, Zahoor,Yadav, Deepika
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- Syntheses, structures, and catalytic activity in Friedel–Crafts acylations of substituted tetramethylcyclopentadienyl molybdenum carbonyl complexes
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Reactions of the substituted tetramethylcyclopentadienes [C5HMe4R] [R?=?tBu, Ph, CH2CH2C(CH3)3] with Mo(CO)3(CH3CN)3 in refluxing xylene gave a series of dinuclear molybdenum carbonyl complexes [(η5-C5Me4R)Mo(CO)3]2 [R?=?tBu (1), Ph (2), CH2CH2C(CH3)3 (3)], [(η5-C5MetBu)Mo(μ-CO)2]2 (4)], and [(η5-C5Me4)tBu]2Mo2O4(μ-O) (5)], respectively. Complexes 1–5 were characterized by elemental analysis, IR, 1H NMR, and 13C NMR spectroscopy. In addition, their crystal structures were determined by X-ray crystal diffraction analysis. The catalytic activities of complexes 1–3 in Friedel–Crafts acylation in the presence of o-chloranil has also been investigated; the reactions were achieved under mild conditions to give the corresponding products in moderate yields.
- Li, Tong,Yan, Xin-Long,Li, Zhan-Wei,Ma, Zhi-Hong,Li, Su-Zhen,Han, Zhan-Gang,Zheng, Xue-Zhong,Lin, Jin
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- Highly efficient p-toluenesulfonic acid-catalyzed alcohol addition or hydration of unsymmetrical arylalkynes
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Under a catalytic amount of PTSA in aqueous or alcoholic media, activated unsymmetrical arylalkynes 1 undergo regioselective water or alcohol addition to afford successfully carbonyl compounds 2 in good to excellent yields. This new environmentally metal-free procedure, which afforded only Markovnikov adducts, is characterized by the mildness of acidic conditions and the excellent regio- and chemoselectivity.
- Olivi, Nathana?l,Thomas, Emmanuel,Peyrat, Jean-Fran?ois,Alami, Mouad,Brion, Jean-Daniel
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- Palladium/copper tandem catalysis for carbon-carbon triple bond cleavage of diaryl acetylenes
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A method for carbon-carbon triple bond cleavage based on palladium/copper tandem catalysis is developed. In this chemistry, anilines and diaryl acetylenes were converted into benzamides through cascade transformations combining palladium-catalyzed hydroamination of alkyne with copper-catalyzed aerobic oxidative C-C bond cleavage.
- Wang, Zhiwei,Fan, Wenyou,Deng, Guo-Jun,Zhou, Wang
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- Palladium-catalyzed synthesis of aryl ketones by coupling of aryl bromides with an acyl anion equivalent
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Palladium-catalyzed couplings of aryl bromides with N-tert-butylhydrazones as acyl anion equivalents to form aryl ketones are reported. The coupling process occurs at the C-position of hydrazones to form N-tert-butyl azo compounds. Isomerization of these azo compounds to the corresponding hydrazones, followed by hydrolysis, gave the desired mixed alkyl aryl ketones. The selectivity of C- versus N-arylation was strongly influenced by the substituent on nitrogen. Arylation at carbon occurred with N-tert-butylhydrazones, whereas N-arylation occurred with N-arylhydrazones. The arylation of hydrazones containing primary and secondary alkyl groups, as well as aryl groups, gave the desired ketones in good yields after hydrolysis. Functional groups on the aromatic ring, such as alkoxy, cyano, trifluoromethyl, carboalkoxy, carbamoyl, and keto groups, were tolerated. This reaction likely occurs by C-C bond-forming reductive elimination from an intermediate containing an η1-diazaallyl ligand. Copyright
- Takemiya, Akihiro,Hartwig, John F.
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- Acylation of aromatic compounds using moisture insensitive InCl3 impregnated mesoporous Si-MCM-41 catalyst
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Acylation of aromatic compounds (benzene, toluene, p-xylene, mesitylene, anisole, naphthalene, methylnaphthalene and methoxynaphthalene) by an acyl chloride (benzoyl chloride, phenylacetyl chloride, propionyl chloride or butyryl chloride) in high yield, in a short reaction period (3 h), even in the presence of moisture in the aromatic substrate or solvent (dichloroethane), can be accomplished at low temperature (80±1°C) using an InCl3 impregnated Si-MCM-41 catalyst in low catalyst concentration.
- Choudhary, Vasant R.,Jana, Suman K.,Patil, Nilesh S.
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- Base-mediated insertion reaction of alkynes into carbon-carbon σ-bonds of ethanones: synthesis of hydroxydienone and chromone derivatives
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Transition-metal free insertions of alkynes into carbon-carbon σ-bonds of ethanones have been reported. These tandem reactions offer an efficient synthesis of hydroxydienones and multi-substituted chromones. This is the first example of base-promoted insertion reactions of isolated carbon-carbon triple bonds into carbon-carbon σ-bonds with active methylene compounds bearing only one electron-withdrawing group.
- Zhang, Fangfang,Yao, Qiyi,Yuan, Yang,Xu, Murong,Kong, Lingkai,Li, Yanzhong
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- Synthesis and antiseizure activity of (E)-1,2-diarylethylidenehydrazine carboximidamides against tonic-clonic seizures: an intracerebroventricular and electrophysiological study
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A series of (E)-1,2-diarylethylidenehydrazine carboximidamides 2a–j were synthesized and characterized by NOESY experiment as anticonvulsant agents and their antiseizure activity was evaluated by intracerebroventricular administration of compounds. Most of the compounds had significant protection against tonic-clonic seizures and 2a was found to be as equipotent as carbamazepine in seizures control. In order to find their anticonvulsant mechanism of action, 2a was subjected to further electrophysiological studies using patch-clamp technique. The results confirmed that this compound is neither a voltage-gated sodium channel blocker nor a NMDA/AMPA antagonist. Although 2a did not show any direct GABA agonistic activity, it could decrease EPSP and increase IPSP frequency without any change in amplitude. Finally, the results indicated most likely a presynaptic GABA-mediated mechanism of 2a for its antiseizure activity such as inhibition of the GABA-T which was validated by molecular docking.
- Firouzjaei, Fariba Abedi,Heidarli, Elmira,Ravan, Shabnam,Hosseini, Sayed Masoud,Naderi, Nima,Almasyan, Kiarash,Sarvary, Afshin,Irannejad, Hamid
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- Acylation of aromatic compounds using moisture insensitive mesoporous Si-MCM-41 supported Ga2O3 catalyst
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Mesoporous Si-MCM-41 supported Ga2O3 is a highly active catalyst for the acylation of aromatic compounds with different acyl chlorides. Moreover, this catalyst is not deactivated by water and hence does not require moisture-free reaction conditions.
- Choudhary, Vasant R.,Jana, Suman K.
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- Copper-catalyzed base-accelerated direct oxidation of C-H bond to synthesize benzils, isatins, and quinoxalines with molecular oxygen as terminal oxidant
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We describe herein an efficient and general copper (II)-catalyzed base-accelerated oxidation of the C-H bond to synthesize benzils and isatins. With similar oxidation system an efficient one-pot procedure for the synthesis of quinoxaline derivatives was realized. The two protocols feature using molecular oxygen as terminal oxidant, low catalyst loading, wide substrate scope, and high functional-group tolerance.
- Yu, Jing-Wen,Mao, Shuai,Wang, Yong-Qiang
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- Addition of arylboronic acids to nitriles in aqueous media catalyzed by a 2,2′-bipyridine-cyclopalladated ferrocenylimine complex
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The addition of arylboronic acids to nitriles catalyzed by a bipyridine-cyclopalladated ferrocenylimine complex in aqueous media was developed. The reactions could be conducted under acidic or basic conditions in aqueous media. The addition of NH4Cl was found to have a drastic effect on the reaction yields. Georg Thieme Verlag Stuttgart.
- Yu, Ajuan,Li, Jingya,Cui, Mengjun,Wu, Yangjie
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- Nickel-Catalyzed Alkylation of Amide Derivatives
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We report the catalytic alkylation of amide derivatives, which relies on the use of nonprecious metal catalysis. Amide derivatives are treated with organozinc reagents, utilizing nickel catalysis, to yield ketone products. The methodology is performed at ambient temperature and is tolerant of variation in both coupling partners. A precursor to a nanomolar glucagon receptor modulator was synthesized using the methodology, underscoring the mild nature of this chemistry and its potential utility in pharmaceutical synthesis. These studies are expected to further promote the use of amides as synthetic building blocks.
- Simmons, Bryan J.,Weires, Nicholas A.,Dander, Jacob E.,Garg, Neil K.
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- Ruthenium(II)-Catalyzed Cross-Coupling of Benzoyl Formic Acids with Toluenes: Synthesis of 2-Phenylacetophenones
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Herein, we report a direct method to synthesize 2-phenylacetophenone through a ruthenium(II)-catalyzed cross-coupling reaction between acyl and benzyl radical. The various derivatives of 2-phenylacetophenone were prepared easily in moderate to good yields. These reactions provide a straightforward pathway to synthesize a variety of ketones bearing various functional groups.
- Chen, Yujie,Dai, Chenyang,Huang, Zhibin,Jiang, Yaqiqi,Shu, Sai,Yang, Shan,Zhao, Yingsheng
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- 1,2-Aryl Migration Induced by Amide C?N Bond-Formation: Reaction of Alkyl Aryl Ketones with Primary Amines Towards α,α-Diaryl β,γ-Unsaturated γ-Lactams
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Rearrangement reactions incorporated into cascade reactions play an important role in rapidly increasing molecular complexity from readily available starting materials. Reported here is a Cu-catalyzed cascade reaction of α-(hetero)aryl-substituted alkyl (hetero)aryl ketones with primary amines that incorporates an unusual 1,2-aryl migration induced by amide C?N bond formation to produce a class of structurally novel α,α-diaryl β,γ-unsaturated γ-lactams in generally good-to-excellent yields. This cascade reaction has a broad substrate scope with respect to primary amines, allows a wide spectrum of (hetero)aryl groups to smoothly undergo 1,2-migration, and tolerates electronically diverse α-substituents on the (hetero)aryl ring of the ketones. Mechanistically, this 1,2-aryl migration may stem from the intramolecular amide C?N bond formation which induces nucleophilic migration of the aryl group from the acyl carbon center to the electrophilic carbon center that is conjugated with the resulting iminium moiety.
- Hu, Rong,Tao, Yigao,Zhang, Xiaofeng,Su, Weiping
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- Selective α-Methylation of Aryl Ketones Using Quaternary Ammonium Salts as Solid Methylating Agents
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We describe the use of phenyl trimethylammonium iodide (PhMe3NI) as an alternative methylating agent for introducing a CH3group in α-position to a carbonyl group. Compared to conventional methylating agents, quaternary ammonium salts have the advantages of being nonvolatile, noncancerogenic, and easy-to-handle solids. This regioselective method is characterized by ease of operational setup, use of anisole as green solvent, and yields up to 85%.
- Templ, Johanna,Schnürch, Michael
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supporting information
p. 4305 - 4315
(2022/03/16)
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- Electrochemical oxidation-induced benzyl C–H carbonylation for the synthesis of aromatic α-diketones
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Electrochemical oxidation-induced direct carbonylation of benzyl C–H bond for the synthesis of aromatic α-diketones is described. In this process, tetrabutylammonium iodide (nBu4NI) not only acts as an electrolyte, but its iodine anion is oxidized to an iodine radical at the anode, acting as a hydrogen atom transfer agent. The iodine radical extracts the benzyl hydrogen atom and causes the carbonylation of the benzyl position, where O2 in the air is used as an oxygen source.
- Tan, Yu-Fang,Chen, Yuan,Li, Rui-Xue,Guan, Zhi,He, Yan-Hong
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supporting information
(2021/12/21)
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- H2O2-mediated room temperature synthesis of 2-arylacetophenones from arylhydrazines and vinyl azides in water
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An environmentally benign, cost-efficient and practical methodology for the room temperature synthesis of 2-arylacetophenones in water has been discovered. The facile and efficient transformation involves the oxidative radical addition of arylhydrazines with α-aryl vinyl azides in the presence of H2O2 (as a radical initiator) and PEG-800 (as a phase-transfer catalyst). From the viewpoint of green chemistry and organic synthesis, the present protocol is of great significance because of using cheap, non-toxic and readily available starting materials and reagents as well as amenability to gram-scale synthesis, which provides an attractive strategy to access 2-arylacetophenones.
- Luo, Mengqiang,Zhang, Yaohong,Fang, Ping,Li, Yan,Qi, Chenze,Li, Yong,Shen, Runpu,Cheng, Kai,Wang, Hai
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supporting information
p. 630 - 635
(2022/02/01)
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- Continuous Flow Acylation of (Hetero)aryllithiums with Polyfunctional N,N-Dimethylamides and Tetramethylurea in Toluene
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The continuous flow reaction of various aryl or heteroaryl bromides in toluene in the presence of THF (1.0 equiv) with sec-BuLi (1.1 equiv) provided at 25 °C within 40 sec the corresponding aryllithiums which were acylated with various functionalized N,N-
- Djukanovic, Dimitrije,Filipponi, Paolo,Heinz, Benjamin,Knochel, Paul,Mandrelli, Francesca,Martin, Benjamin,Mostarda, Serena
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supporting information
p. 13977 - 13981
(2021/09/13)
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- Asymmetric Catalytic Epoxidation of Terminal Enones for the Synthesis of Triazole Antifungal Agents
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An enantioselective epoxidation of α-substituted vinyl ketones was realized to construct the key epoxide intermediates for the synthesis of various triazole antifungal agents. The reaction proceeded efficiently in high yields with good enantioselectivities by employing a chiral N,N′-dioxide/ScIII complex as the chiral catalyst and 35% aq. H2O2 as the oxidant. It enabled the facile transformation for optically active isavuconazole, efinaconazole, and other potential antifungal agents.
- Feng, Xiaoming,He, Qianwen,Liu, Xiaohua,Zhang, Dong,Zhang, Fengcai
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supporting information
p. 6961 - 6966
(2021/09/11)
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- Benzylic Aroylation of Toluenes Mediated by a LiN(SiMe3)2/Cs+System
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Chemoselective deprotonative functionalization of benzylic C-H bonds is challenging, because the arene ring contains multiple aromatic C(sp2)-H bonds, which can be competitively deprotonated and lead to selectivity issues. Recently it was found that bimetallic [MN(SiMe3)2 M = Li, Na]/Cs+ combinations exhibit excellent benzylic selectivity. Herein, is reported the first deprotonative addition of toluenes to Weinreb amides mediated by LiN(SiMe3)2/CsF for the synthesis of a diverse array of 2-arylacetophenones. Surprisingly, simple methyl benzoates also react with toluenes under similar conditions to form 2-arylacetophenones without double addition to give tertiary alcohol products. This finding greatly increases the practicality and impact of this chemistry. Some challenging substrates with respect to benzylic deprotonations, such as fluoro and methoxy substituted toluenes, are selectively transformed to 2-aryl acetophenones. The value of benzylic deprotonation of 3-fluorotoluene is demonstrated by the synthesis of a key intermediate in the preparation of Polmacoxib.
- Dai, Ziteng,Gu, Yuanyun,Li, Jie,Mao, Jianyou,Walsh, Patrick J.,Wang, Yan-En,Xiong, Dan,Yuan, Yaqi,Zhang, Zhen
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supporting information
(2022/01/14)
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- Combined Theoretical and Experimental Studies Unravel Multiple Pathways to Convergent Asymmetric Hydrogenation of Enamides
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We present a highly efficient convergent asymmetric hydrogenation of E/Z mixtures of enamides catalyzed by N,P-iridium complexes supported by mechanistic studies. It was found that reduction of the olefinic isomers (E and Z geometries) produces chiral amides with the same absolute configuration (enantioconvergent hydrogenation). This allowed the hydrogenation of a wide range of E/Z mixtures of trisubstituted enamides with excellent enantioselectivity (up to 99% ee). A detailed mechanistic study using deuterium labeling and kinetic experiments revealed two different pathways for the observed enantioconvergence. For α-aryl enamides, fast isomerization of the double bond takes place, and the overall process results in kinetic resolution of the two isomers. For α-alkyl enamides, no double bond isomerization is detected, and competition experiments suggested that substrate chelation is responsible for the enantioconvergent stereochemical outcome. DFT calculations were performed to predict the correct absolute configuration of the products and strengthen the proposed mechanism of the iridium-catalyzed isomerization pathway.
- Yang, Jianping,Massaro, Luca,Krajangsri, Suppachai,Singh, Thishana,Su, Hao,Silvi, Emanuele,Ponra, Sudipta,Eriksson, Lars,Ahlquist, M?rten S. G.,Andersson, Pher G.
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supporting information
p. 21594 - 21603
(2021/12/27)
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- Iron-Catalyzed Enantioselective Radical Carboazidation and Diazidation of α,β-Unsaturated Carbonyl Compounds
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Azidation of alkenes is an efficient protocol to synthesize organic azides which are important structural motifs in organic synthesis. Enantioselective radical azidation, as a useful strategy to install a C-N3 bond, remains challenging due to the inherently instability and unique structure of radicals. Here, we disclose an efficient enantioselective radical carboazidation and diazidation of α,β-unsaturated ketones and amides catalyzed by chiral N,N′-dioxide/Fe(OTf)2 complexes. An array of substituted alkenes was transformed to the corresponding α-azido carbonyl derivatives in good to excellent enantioselectivities, benefiting the preparation of chiral α-amino ketones, vicinal amino alcohols, and vicinal diamines. Control experiments and mechanistic studies proved the radical pathway in the reaction process. The DFT calculations showed that the azido transferred to the radical intermediate via an intramolecular five-membered transition state with the internal nitrogen of the Fe-N3 species.
- Dong, Shunxi,Feng, Xiaoming,He, Jun,Liu, Wen,Liu, Xiaohua,Pu, Maoping,Wu, Yun-Dong,Zhang, Tinghui
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supporting information
p. 11856 - 11863
(2021/08/16)
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- Palladium-catalyzed synthesis of α-aryl acetophenones from styryl ethers and aryl diazonium saltsviaregioselective Heck arylation at room temperature
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Preparation of α-aryl acetophenones from styryl ethers and aryldiazonium salts is described. The reaction is catalyzed by palladium acetate at room temperature in the absence of ligand and base. The developed method is highly attractive in terms of reaction conditions, substrate scope, functional group tolerance and yields. Synthetic applications of the present method are demonstrated by preparing α-aryl indoles and 3-aryl isocoumarin from styryl ethers.
- Kandasamy, Jeyakumar,Lee, Yong Rok,Singh, Adesh Kumar,Venkatesh, Rapelly
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supporting information
p. 7832 - 7837
(2021/09/28)
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- C-H Alkylation of Aldehydes by Merging TBADT Hydrogen Atom Transfer with Nickel Catalysis
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Catalyst controlled site-selective C-H functionalization is a challenging but powerful tool in organic synthesis. Polarity-matched and sterically controlled hydrogen atom transfer (HAT) provides an excellent opportunity for site-selective functionalization. As such, the dual Ni/photoredox system was successfully employed to generate acyl radicals from aldehydes via selective formyl C-H activation and subsequently cross-coupled to generate ketones, a ubiquitous structural motif present in the vast majority of natural and bioactive molecules. However, only a handful of examples that are constrained to the use of aryl halides are developed. Given the wide availability of amines, we developed a cross-coupling reaction via C-N bond cleavage using the economic nickel and TBADT catalyst for the first time. A range of alkyl and aryl aldehydes were cross-coupled with benzylic and allylic pyridinium salts to afford ketones with a broad spectrum of functional group tolerance. High regioselectivity toward formyl C-H bonds even in the presence of α-methylene carbonyl or α-amino/oxy methylene was obtained.
- Murugesan, Vetrivelan,Ganguly, Anirban,Karthika, Ardra,Rasappan, Ramesh
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p. 5389 - 5393
(2021/07/21)
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- Versatile and base-free copper-catalyzed α-arylations of aromatic ketones using diaryliodonium salts
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A ligand and base-free copper catalyzed synthetic method for the efficient α-arylation of aromatic ketones is described. In order to avoid strong bases, ketone-derived silyl enol ethers were employed. Their reaction with diaryliodonium salts as aryl source provided the intermolecular C–C coupling displaying good functional group tolerance and requiring low catalyst loading.
- Bouquin, Maxime,Jaroschik, Florian,Taillefer, Marc
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- Benzylic aroylation of toluenes with unactivated tertiary benzamides promoted by directed ortho-lithiation
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The deprotonative functionalization of toluenes, for their weak acidity, generally needs strong bases, thus leading to the requirement of harsh conditions and the generation of by-products. Direct nucleophilic acyl substitution reaction of amides with organometallic reagents could provide an ideal solution for ketone synthesis. However, the inert amides and highly reactive organometallic reagents bring great challenges for an efficient and selective synthetic approach. Herein, we reported an lithium diisopropylamide (LDA)-promoted benzylic aroylation of toluenes with unactivated tertiary benzamides, providing a direct and efficient synthesis of various aryl benzyl ketones. This process features a kinetic deprotonative functionalization of toluenes with a readily available base LDA. Mechanism studies revealed that the directed ortho-lithiation of the tertiary benzamide with LDA promoted the benzylic kinetic deprotonation of toluene and triggered the nucleophilic acyl substitution reaction with the amide. [Figure not available: see fulltext.].
- Bao, Can-Can,Luo, Yan-Long,Du, Hui-Zhen,Guan, Bing-Tao
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p. 1349 - 1354
(2021/07/12)
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- Ring size and nothing else matters: unusual regioselectivity of alkyne hydration by NHC gold(i) complexes
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We have investigated the role of ring sizes and substituents in NHC ligands in some (NHC)Au(i) complexes in the hydration of internal alkynes. Despite the fact that using (NHC)Au(i) complexes in the hydration of diarylacetylenes leads to Markovnikov-type products, the precise tuning of ligands allows changing the regioselectivity in arylalkylacetylene hydration to the anti-Markovnikov-type.
- Ageshina, Alexandra A.,Asachenko, Andrey F.,Chesnokov, Gleb A.,Minaeva, Lidiya I.,Nechaev, Mikhail S.,Philippova, Anna N.,Rzhevskiy, Sergey A.,Topchiy, Maxim A.
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supporting information
p. 5686 - 5689
(2021/06/16)
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- Gold-Catalyzed [3+2]-Annulations of α-Aryl Diazoketones with the Tetrasubstituted Alkenes of Cyclopentadienes: High Stereoselectivity and Enantioselectivity
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This work reports gold-catalyzed [3+2]-annulations of α-diazo ketones with highly substituted cyclopentadienes, affording bicyclic 2,3-dihydrofurans with high regio- and stereoselectivity. The reactions highlights the first success of tetrasubstituted alkenes to undergo [3+2]-annulations with α-diazo carbonyls. The enantioselective annulations are also achieved with high enantioselectivity using chiral forms of gold and phosphoric acid. Our mechanistic analysis supports that cyclopentadienes serve as nucleophiles to attack gold carbenes at the more substituted alkenes, yielding gold enolates that complex with chiral phosphoric acid to enhance the enantioselectivity.
- Chen, Ching-Nung,Cheng, Wei-Min,Wang, Jian-Kai,Chao, Tzu-Hsuan,Cheng, Mu-Jeng,Liu, Rai-Shung
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supporting information
p. 4479 - 4484
(2021/01/21)
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- Aerobic oxygenation of α-methylene ketones under visible-light catalysed by a CeNi3complex with a macrocyclic tris(salen)-ligand
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A hetero-tetranuclear CeNi3 complex with a macrocyclic ligand catalysed the aerobic oxygenation of a methylene group adjacent to a carbonyl group under visible-light radiation to produce the corresponding α-diketones. The visible-light induced homolysis of the Ce-O bond of a bis(enolate) intermediate is proposed prior to aerobic oxygenation.
- Fujiwara, Sakiko,Kon, Yoshihiro,Mashima, Kazushi,Nagae, Haruki,Okuda, Jun,Sakamoto, Kazutaka,Sato, Kazuhiko,Schindler, Tobias
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supporting information
p. 11169 - 11172
(2021/11/04)
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- Site-Specific Oxidation of (sp3)C-C(sp3)/H Bonds by NaNO2/HCl
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A site-specific oxidation of (sp3)C-C(sp3) and (sp3)C-H bonds in aryl alkanes by the use of NaNO2/HCl was explored. The method is chemical-oxidant-free, transition-metal-free, uses water as the solvent, and proceeds under mild conditions, making it valuable and attractive to synthetic organic chemistry.
- Zhao, Jianyou,Shen, Tong,Sun, Zhihui,Wang, Nengyong,Yang, Le,Wu, Jintao,You, Huichao,Liu, Zhong-Quan
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p. 4057 - 4061
(2021/05/26)
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- Regioselection in the synthesis of 4-benzyltetral-1-ones and the new 4-arylbenzosuber-1-ones
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The intramolecular Friedel-Crafts acylation of 4,5-diarylpentanoic acids has the possibility to cyclise to either a 6-membered ring to give 4-benzyltetral-1-one or a 7-membered ring to give 4-arylbenzosuber-1-one. Of these, only the former compound class has previously been reported. The impact of the substituents positioning on the outcome of the cyclisation has been investigated. The complete formation of either the tetralone or the benzosuberone regioisomer was possible under the same reaction conditions, dependent upon the ring activation and/or deactivation of the chosen substituents. Selected bromo or methoxy substituents could be used as auxiliaries, included in precursors to afford the desired regioisomer and then subsequently removed.
- Truong, Daniel,Howard, Brittany L.,Thompson, Philip E.
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- Cobalt(II)-Catalyzed Stereoselective Olefin Isomerization: Facile Access to Acyclic Trisubstituted Alkenes
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Stereoselective synthesis of trisubstituted alkenes is a long-standing challenge in organic chemistry, due to the small energy differences between E and Z isomers of trisubstituted alkenes (compared with 1,2-disubstituted alkenes). Transition metal-catalyzed isomerization of 1,1-disubstituted alkenes can serve as an alternative approach to trisubstituted alkenes, but it remains underdeveloped owing to issues relating to reaction efficiency and stereoselectivity. Here we show that a novel cobalt catalyst can overcome these challenges to provide an efficient and stereoselective access to a broad range of trisubstituted alkenes. This protocol is compatible with both mono- and dienes and exhibits a good functional group tolerance and scalability. Moreover, it has proven to be a useful tool to construct organic luminophores and a deuterated trisubstituted alkene. A preliminary study of the mechanism suggests that a cobalt-hydride pathway is involved in the reaction. The high stereoselectivity of the reaction is attributed to both a π-πstacking effect and the steric hindrance between substrate and catalyst.
- Zhang, Sheng,Bedi, Deepika,Cheng, Lu,Unruh, Daniel K.,Li, Guigen,Findlater, Michael
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supporting information
p. 8910 - 8917
(2020/12/23)
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- Ketone Synthesis from Benzyldiboronates and Esters: Leveraging α-Boryl Carbanions for Carbon-Carbon Bond Formation
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An alkoxide-promoted method for the synthesis of ketones from readily available esters and benzyldiboronates is described. The synthetic method is compatible with a host of sterically differentiated alkyl groups, alkenes, acidic protons α to carbonyl groups, tertiary amides, and aryl rings having common organic functional groups. With esters bearing α-stereocenters, high enantiomeric excess was maintained during ketone formation, establishing minimal competing racemization by deprotonation. Monitoring the reaction between benzyldiboronate and LiOtBu in THF at 23 °C allowed for the identification of products arising from deborylation to form an α-boryl carbanion, deprotonation, and alkoxide addition to form an "-ate" complex. Addition of 4-trifluoromethylbenzoate to this mixture established the α-boryl carbanion as the intermediate responsible for C-C bond formation and ultimately ketone synthesis. Elucidation of the role of this intermediate leveraged additional bond-forming chemistry and enabled the one-pot synthesis of ketones with α-halogen atoms and quaternary centers with four-different carbon substituents.
- Lee, Boran,Chirik, Paul J.
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supporting information
p. 2429 - 2437
(2020/03/03)
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- Intermolecular oxyarylation of olefins with aryl halides and TEMPOH catalyzed by the phenolate anion under visible light
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The phenolate anion was discovered as a new photocatalyst with strong reduction potentials. Under visible light irradiation, the phenolate anion enabled the reduction of (hetero)aryl halides (including electron-rich aryl chlorides) to (hetero)aryl radicals through single electron transfer. Based on this new photocatalyst, a novel and efficient photocatalytic protocol for the intermolecular oxyarylation of olefins with aryl halides and TEMPOH was developed. The developed three-component coupling reaction proceeded under redox-neutral reaction conditions with stable and readily available synthons and exhibited broad substrate scope. The utility of this process was further highlighted by the diversified chemical manipulation of the resulting oxyarylation products and the late-stage modification of active pharmaceutical ingredients.
- Li, Xipan,Liang, Kangjiang,Liu, Qian,Shen, Lei,Wei, Delian,Xia, Chengfeng,Zheng, Liyan
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p. 6996 - 7002
(2020/07/23)
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- Synthesis of unsymmetrical ketones by applying visible-light benzophenone/nickel dual catalysis for direct benzylic acylation
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Herein, we report a dual catalytic system for the direct benzylic C-H acylation reaction furnishing a variety of unsymmetrical ketones. A benzophenone-derived photosensitizer combined with a nickel catalyst has been established as the catalytic system. Both acid chlorides and anhydrides are able to acylate the benzylic position of toluene and other methylbenzenes. The method offers a valuable alternative to late transition metal catalyzed C-H acylation reactions.
- Krach, Patricia E.,Dewanji, Abhishek,Yuan, Tingting,Rueping, Magnus
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supporting information
p. 6082 - 6085
(2020/06/18)
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- Blue Light Promoted Difluoroalkylation of Aryl Ketones: Synthesis of Quaternary Alkyl Difluorides and Tetrasubstituted Monofluoroalkenes
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A facile and cost-effective method for the preparation of fluoroalkylated compounds has been described by the direct photoexcitation of halofluoroalkanes with blue light absorptivity, enabling the difluoroalkylation of aryl ketones. The methodology has provided an efficient, mild, and catalyst-free synthetic method for quaternary difluoroalkylated arenes and tetrasubstituted monofluoroalkenes.
- Li, Kangkui,Chen, Jingchao,Yang, Chunhui,Zhang, Keyang,Pan, Chunxiang,Fan, Baomin,Fan, Baomin
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supporting information
p. 4261 - 4265
(2020/06/04)
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- A copper-catalyzed insertion of sulfur dioxide: Via radical coupling
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A copper-catalyzed three-component reaction of O-acyl oximes, DABCO·(SO2)2, and 2H-azirines under mild conditions has been achieved. This protocol provides an efficient route for the construction of various tetrasubstituted β-sulfonyl N-unprotected enamines in moderate to good yields with excellent stereoselectivity and regioselectivity. Notably, this method represents a rare example of 2H-azirines as useful synthons for β-functionalized N-unprotected enamines. Preliminary mechanistic studies indicate that the reaction proceeds through coupling of a sulfonyl radical and α-carbon radical via copper-catalyzed ring-opening C-C bond cleavage of O-acyl oxime and C-N bond cleavage of 2H-azirine with the insertion of sulfur dioxide.
- Zhang, Jun,Yang, Min,Liu, Jin-Biao,He, Fu-Sheng,Wu, Jie
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supporting information
p. 3225 - 3228
(2020/03/23)
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- 2,2-Diazido-1,2-diarylethanones: Synthesis and Reactivity with Primary Amines
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We describe the synthesis and reactivity of a new class of diazidated compounds: the 2,2-diazido-1,2-diarylethanones. The diazides are easily accessible from 1,2-diarylethanones through a mild and simple protocol for the direct oxidative diazidation, using iodine and sodium azide in DMSO at room temperature. In studies towards their reactivity with amine nucleophiles under basic conditions, the diazides are shown to undergo a controlled fragmentation reaction that provides a straightforward access to the corresponding amides. In stark contrast to our previous results on the amine-triggered fragmentation of diazidated compounds, aromatic nitriles are found to be by-products of synthetic value. The net reaction consisting of diazidation and subsequent fragmentation, thus, provides a simple way to convert 1,2-diarylethanones into both aromatic amides and nitriles.
- Holzschneider, Kristina,H?ring, Andreas P.,Kirsch, Stefan F.
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p. 2824 - 2831
(2019/04/30)
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- Electrochemical [4+2] Annulation-Rearrangement-Aromatization of Styrenes: Synthesis of Naphthalene Derivatives
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We report the first electrochemical strategy to synthesize functionalized naphthalene derivatives through [4+2] annulation—rearrangement–aromatization from styrenes under mild conditions. The electrolysis does not require metals, oxidants and high valence substrates, indicating the atom and step-economy ideals. The dehydrodimer produced through [4+2] cycloaddition of 4-methoxy α-methyl styrene is isolated and proved to be the key intermediate for the following oxydehydrogenation to form carbon cation, which undergoes rearrangement–aromatization to afford the final products. This reaction represents a powerful access to construct multi-substituted naphthalene blocks in a single step.
- Ma, Yueyue,Lv, Jufeng,Liu, Chengyu,Yao, Xiantong,Yan, Guoming,Yu, Wei,Ye, Jinxing
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supporting information
p. 6756 - 6760
(2019/04/17)
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- Discovery of the First in Vivo Active Inhibitors of the Soluble Epoxide Hydrolase Phosphatase Domain
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The emerging pharmacological target soluble epoxide hydrolase (sEH) is a bifunctional enzyme exhibiting two different catalytic activities that are located in two distinct domains. Although the physiological role of the C-terminal hydrolase domain is well-investigated, little is known about its phosphatase activity, located in the N-terminal phosphatase domain of sEH (sEH-P). Herein we report the discovery and optimization of the first inhibitor of human and rat sEH-P that is applicable in vivo. X-ray structure analysis of the sEH phosphatase domain complexed with an inhibitor provides insights in the molecular basis of small-molecule sEH-P inhibition and helps to rationalize the structure-activity relationships. 4-(4-(3,4-Dichlorophenyl)-5-phenyloxazol-2-yl)butanoic acid (22b, SWE101) has an excellent pharmacokinetic and pharmacodynamic profile in rats and enables the investigation of the physiological and pathophysiological role of sEH-P in vivo.
- Kramer, Jan S.,Woltersdorf, Stefano,Duflot, Thomas,Hiesinger, Kerstin,Lillich, Felix F.,Kn?ll, Felix,Wittmann, Sandra K.,Klingler, Franca-M.,Brunst, Steffen,Chaikuad, Apirat,Morisseau, Christophe,Hammock, Bruce D.,Buccellati, Carola,Sala, Angelo,Rovati, G. Enrico,Leuillier, Matthieu,Fraineau, Sylvain,Rondeaux, Julie,Hernandez-Olmos, Victor,Heering, Jan,Merk, Daniel,Pogoryelov, Denys,Steinhilber, Dieter,Knapp, Stefan,Bellien, Jeremy,Proschak, Ewgenij
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p. 8443 - 8460
(2019/10/16)
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- Combined Photoredox/Enzymatic C?H Benzylic Hydroxylations
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Chemical transformations that install heteroatoms into C?H bonds are of significant interest because they streamline the construction of value-added small molecules. Direct C?H oxyfunctionalization, or the one step conversion of a C?H bond to a C?O bond, could be a highly enabling transformation due to the prevalence of the resulting enantioenriched alcohols in pharmaceuticals and natural products,. Here we report a single-flask photoredox/enzymatic process for direct C?H hydroxylation that proceeds with broad reactivity, chemoselectivity and enantioselectivity. This unified strategy advances general photoredox and enzymatic catalysis synergy and enables chemoenzymatic processes for powerful and selective oxidative transformations.
- Betori, Rick C.,May, Catherine M.,Scheidt, Karl A.
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p. 16490 - 16494
(2019/11/03)
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- NCN-Pincer palladium complexes immobilized on MCM-41 molecular sieve: Application in Α-arylation reactions
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Aromatic para-functionalized NCN pincer compounds tethered to a triethoxysilane moiety through a carbamate linkage were immobilized on ordered MCM-41 molecular sieve using a grafting process. The acquired immobilized organometallic pincer complexes were synthesized in high yields with no complex degradation and characterized by IR sprctroscopy, elemental content analysis. Nitrogen physisorption, XRD and TEM revealed that the mesoporous structure was retained during the immobilization process. The hybrid materials were applied as Lewis acid catalysts in the α-arylation reaction between aryl ketones and aryl halides, with the yield up to 95%. The tendency to form mono- or di-arylated products was investigated and the catalyst could be easily recovered and reused in five runs without a significant loss in its activity.
- Kai, Wang,Qian, Hua,Liu, Dabin,Ye, Zhiwen
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- Synthesis and catalytic reactivity in Friedel–Crafts acylations of monobridged bis(cyclopentadienyl)molybdenum(I) carbonyl complexes
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When the monobridged biscyclopentadienes (C5H5)R(C5H5) [R = C(CH3)2 (1), Si(CH3)2 (2), C(CH2)5 (3)] reacted with Mo(CO)6 in refluxing xylene, the corresponding complexes [(η5-C5H4)2R][Mo(CO)3]2 [R = C(CH3)2 (4), Si(CH3)2 (5), C(CH2)5 (6)] were obtained. These complexes were separated by chromatography and characterized by elemental analysis, IR, and 1H NMR spectroscopy. The molecular structures of 4 and 5 were determined by X-ray diffraction analysis. Friedel–Crafts acylation reactions of anisole derivatives with aromatic or aliphatic acyl chlorides catalyzed by complexes 4–6 showed that all of these monobridged bis(cyclopentadienyl)molybdenum carbonyl complexes have catalytic activity.
- Yan, Xin Long,Zhang, Ning,Hao, Zhi Qiang,Ma, Zhi Hong,Han, Zhan Gang,Zheng, Xue Zhong,Lin, Jin
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- Further studies on the application of vinylogous amides and β-halovinylaldehydes to the regiospecific synthesis of unsymmetrical, polyfunctionalized 2,3,4- and 1,2,3,4- substituted pyrroles
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Highly functionalized pyrroles with appropriate regiochemical functionality represent an important class of marine natural products and potential drug candidates. We describe herein a detailed study of the reaction of α-aminoacid esters with vinylogous amides and also β-halovinylaldehydes for the regiospecific synthesis of 2,3,4-trisubstituted and 1,2,3,4-tetrasubstituted pyrroles. Since the vinylogous amides and β-halovinylaldehydes are readily available precursors, rapid access to a wide variety of unsymmetrically substituted pyrroles is accomplished via this methodology.
- Gupton, John T.,Shimozono, Alex,Crawford, Evan,Ortolani, Joe,Clark, Evan,Mahoney, Matt,Heese, Campbell,Noble, Jeffrey,Mandry, Carlos Perez,Kanters, Rene,Dominey, Raymond N.,Goldman, Emma W.,Sikorski, James A.,Fisher, Daniel C.
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p. 2650 - 2663
(2018/04/23)
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- Reaction of arynes with trifluoroacetylated β-diketones: Novel formation of isocoumarins and phenanthrenes
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Polysubstituted isocoumarins were synthesized by the reaction of substituted 2-(trimethylsilyl)aryl triflates with trifluoromethylated β-diketones in the presence of CsF. The reaction proceeded through carbon-carbon bond insertion of aryne and intramolecular cyclization to form intermediates of alcohol anions, which extruded trifluoromethyl anion to afford isocoumarins. By using CuBr as a catalyst, 2 eq. of aryne reacted with β-diketones to afford phenanthrenes and 1,2-diarylethanones. Although reaction of 2-(trimethylsilyl)phenyl triflate with 1,1,1-trifluoro-4′-methylbenzoylacetone in the presence of CsF gave 3-(4′-methylphenyl)isocoumarin in 67% yield, addition of 0.2 eq. of CuCN resulted in the formation of 9-(4-methylbenzoyl)-10-trifluoromethylphenanthrene in 35% yield.
- Okuma, Kentaro,Tanabe, Yukiko,Fukami, Takuto,Ishibashi, Yuto
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- Pd-catalyzed Oxidative Cross-coupling of Alkyl Chromium(0) Fischer Carbene Complexes with Organoboronic Acids
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Alkyl chromium(0) carbene complexes have been explored as the cross-coupling partners in the palladium-catalyzed reaction with aryl or alkenyl boronic acids. This coupling reaction displays the versatile reactivities of alkyl chromium(0) carbenes under palladium catalysis. Mechanistically, this transformation is proposed to involve deprotonation of the alkyl chromium carbene substrate to generate a vinyl chromium anion intermediate that undergoes transmetalation to organopalladium species and reductive elimination.
- Wang, Kang,Yang, Jinghui,Yao, Xingqi,Wang, Jianbo
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supporting information
p. 3165 - 3168
(2018/10/15)
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- Mn/Cu catalyzed addition of arylboronic acid to nitriles: Direct synthesis of arylketones
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A direct and efficient synthesis of arylketones via arylboronic acid addition to nitriles in presence of inexpensive Mn/Cu catalytic system is reported. The use of non-precious Mn and Cu salts has been found to be highly advantageous both in terms of accessibility as well as cost effectiveness. A series of arylboronic acids as well as nitriles were used to synthesize a variety of symmetrical and unsymmetrical arylketones. Based on the literature studies, the reaction mechanism is anticipated to go through an aryl radical intermediate which reacted with the copper activated nitrile to give the desired arylketones after the hydrolysis of the imine intermediate.
- Moustafa, Dina,Sweet, Chelsea,Lim, Hyun,Calalpa, Brenda,Kaur, Parminder
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p. 3816 - 3820
(2018/09/18)
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- Metal-free synthesis of ketones by visible-light induced aerobic oxidative radical addition of aryl hydrazines to alkenes
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A green and cost-effective method has been developed for the conversion of alkenes to ketones under metal-free conditions. The reaction involves the oxidative addition of alkenes with aryl radicals, which are generated by visible-light induced aerobic oxidation of arylhydrazines. The key features of this reaction include broad substrate scope, readily available reagents and amenability to gram-scale synthesis.
- Ding, Ya,Zhang, Wenkai,Li, Hao,Meng, Yunge,Zhang, Te,Chen, Qiu-Yun,Zhu, Chunyin
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supporting information
p. 2941 - 2944
(2017/07/24)
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- Syntheses, structures and catalytic activity for Friedel-Crafts reactions of substituted indenyl rhenium carbonyl complexes
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The complexes [(η5-C9H6R)Re(CO)3] [R?=?nBu (8), tBu (9), CH(CH2)4 (10), Ph (11), Bz (12), 4-methoxyphenyl (13), 4-chlorophenyl (14)] were synthesized by refluxing substituted indenyl ligands [C9H7R] [R?=?nBu (1), tBu (2), CH(CH2)4 (3), Ph (4), Bz (5), 4-methoxyphenyl (6), 4-chlorophenyl (7)], and Re2(CO)10 in decalin. The molecular structures of 9, 10, 12, and 13 were determined by X-ray diffraction analysis. These four crystals have similar molecular structures of the mononuclear carbonyl complex. In each of these molecules, Re is η5-coordinated to the five-membered ring of the indenyl group. Complexes 8–14 have catalytic activity for Friedel-Crafts reactions of aromatic compounds with a variety of alkylation and acylation reagents. Compared with traditional catalysts, these mononuclear metal carbonyl complexes have obvious advantages such as high activities, mild reaction conditions, high selectivity, and environmentally friendly chemistry.
- Ma, Zhihong,Zhang, Xinli,Wang, Hong,Han, Zhangang,Zheng, Xuezhong,Lin, Jin
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p. 709 - 721
(2017/02/05)
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- Synthesis and neuroprotective activity of novel 1,2,4-triazine derivatives with ethyl acetate moiety against H2O2 and Aβ-induced neurotoxicity
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A series of 5,6-diaryl-1,2,4-triazine-3-thioacetate derivatives 3a–f, 8a–d and their regioisomer 8e were synthesized. Neuroprotective activity of compounds was assessed against H2O2 and β-amyloid-induced toxicity in PC12 and SH-SY5Y cells respectively. Surprisingly, ethyl 2-(5-(4-chlorophenyl)-6-(4-methoxyphenyl)-3-thioxo-1,2,4-triazin-2(3H)-yl)acetate (8e) was the most potent compound in both tests with EC50 of 14 μM in H2O2 induced apoptosis and also could increase 40% of cell viability revealed by cytometric analysis with Annexin V/PI staining. It was also shown that regioisomer 8e has more neuroprotective activity than Quercetin in β-amyloid induced toxicity. Morphologic evaluation of cells by DAPI staining and TUNEL assay showed the effectiveness of this compound to improve neurite outgrowth in neuronal cells.
- Tuylu Kucukkilinc, Tuba,Safari Yanghagh, Kamaledin,Ayazgok, Beyza,Ali Roknipour, Mohammad,Homayouni Moghadam, Farshad,Moradi, Alireza,Emami, Saeed,Amini, Mohsen,Irannejad, Hamid
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p. 3057 - 3071
(2017/10/06)
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- Radical-Based C?C Bond-Forming Processes Enabled by the Photoexcitation of 4-Alkyl-1,4-dihydropyridines
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We report herein that 4-alkyl-1,4-dihydropyridines (alkyl-DHPs) can directly reach an electronically excited state upon light absorption and trigger the generation of C(sp3)-centered radicals without the need for an external photocatalyst. Selective excitation with a violet-light-emitting diode turns alkyl-DHPs into strong reducing agents that can activate reagents through single-electron transfer manifolds while undergoing homolytic cleavage to generate radicals. We used this photochemical dual-reactivity profile to trigger radical-based carbon–carbon bond-forming processes, including nickel-catalyzed cross-coupling reactions.
- Buzzetti, Luca,Prieto, Alexis,Roy, Sudipta Raha,Melchiorre, Paolo
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supporting information
p. 15039 - 15043
(2017/11/20)
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- Palladium-Catalyzed Denitrogenative Synthesis of Aryl Ketones from Arylhydrazines and Nitriles Using O2 as Sole Oxidant
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An efficient and simple palladium-catalyzed approach for the synthesis of aryl ketones from low-cost nitriles and arylhydrazines using molecular oxygen (O2) as sole oxidant via C-N bond cleavage is reported. Various aryl ketones were synthesized in moderate to good yields under mild conditions. A possible mechanism involving the PdII/Pd0 catalytic cycle process is depicted, and a cationic palladium intermediate was detected by ESI-MS.
- Wang, Xu,Huang, Yubing,Xu, Yanli,Tang, Xiaodong,Wu, Wanqing,Jiang, Huanfeng
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p. 2211 - 2218
(2017/02/26)
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- Novel bisamide palladium(II) pincer complexes: effective catalysts in α-arylation of ketones
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Three benzenedicarboxamide ligands (L) were designed and synthesized, and each was used to prepare a palladium(II) complex Pd(L)Br and Pd(L)(OAc). These NCN pincer complexes were used to catalyze the α-arylations of a variety of ketones with aryl chlorides or bromides in various solvents, and moderate-to-excellent yields were obtained (up to 95%). Further research showed that unactivated and sterically hindered aryl halides and ketones are also suitable substrates for the synthesis of α-arylation. Graphical Abstract: [Figure not available: see fulltext.].
- Kai, Wang,Liu, Dabin,Qian, Hua,Ye, Zhiwen
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p. 443 - 450
(2017/07/12)
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- An unusual chemoselective oxidation strategy by an unprecedented exploration of an electrophilic center of DMSO: A new facet to classical DMSO oxidation
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A conceptually new dimethyl sulfoxide (DMSO) based oxidation process without the use of any activator has been demonstrated for the oxidation of active methylenes and benzhydrols. The developed protocol utilizes the electrophilic center of DMSO for oxidation, which was unexplored before. Mechanistic investigation has confirmed that the source of oxygen is DMSO.
- Chebolu, Rajesh,Bahuguna, Ashish,Sharma, Reena,Mishra, Vivek Kumar,Ravikumar
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supporting information
p. 15438 - 15441
(2015/10/20)
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