132971-87-0Relevant academic research and scientific papers
Ag2CO3-catalyzed efficient synthesis of internal or terminal propargylicamines and chalcones via A3-coupling under solvent-free condition
Li, Ningbo,Xu, Shitang,Wang, Xueyan,Xu, Li,Qiao, Jie,Liang, Zhiwu,Xu, Xinhua
, p. 3993 - 3997 (2021/05/31)
Several simple, fast and practical protocols have been developed to synthesize internal or terminal propargylamines and chalcones via A3-coupling reaction of aldehydes, amines, and alkynes catalyzed by an easily available catalyst Ag2CO3 under solvent-free condition. The reaction proceeded smoothly to deliver various products in good-to-excellent yields with good functional group tolerance. Gram-scale preparation, bioactive molecule synthesis and asymmetric substrates have been demonstrated. Furthermore, plausible mechanisms for the synthesis of different products have been proposed.
Borane-Catalyzed, Chemoselective Reduction and Hydrofunctionalization of Enones Enabled by B-O Transborylation
Nicholson, Kieran,Langer, Thomas,Thomas, Stephen P.
supporting information, p. 2498 - 2504 (2021/04/13)
The use of stoichiometric organoborane reductants in organic synthesis is well established. Here these reagents have been rendered catalytic through an isodesmic B-O/B-H transborylation applied in the borane-catalyzed, chemoselective alkene reduction and formal hydrofunctionalization of enones. The reaction was found to proceed by a 1,4-hydroboration of the enone and B-O/B-H transborylation with HBpin, enabling catalyst turnover. Single-turnover and isotopic labeling experiments supported the proposed mechanism of catalysis with 1,4-hydroboration and B-O/B-H transborylation as key steps.
Highly Enantioselective Epoxidation of α,β-Unsaturated Ketones Using Amide-Based Cinchona Alkaloids as Hybrid Phase-Transfer Catalysts
Jurczak, Janusz,Majdecki, Maciej,Tyszka-Gumkowska, Agata
supporting information, (2020/11/13)
A series of 20 one chiral epoxides were obtained with excellent yields (up to 99%) and enantioselectivities (up to >99% ee) using hybrid amide-based Cinchona alkaloids. Our method is characterized by low catalyst loading (0.5 mol %) and short reaction times. Moreover, the epoxidation process can be carried out in 10 cycles, without further catalyst addition to the reaction mixture. This methodology significantly enhance the scale of the process using very low catalyst loading.
Development of 5-(Aryl)-3-phenyl-1H-pyrazole Derivatives as Potent Antimicrobial Compounds
Nagendra Chowdary,Umashankara,Dinesh,Girish,Ramesha Baba
, p. 45 - 50 (2018/12/11)
A series of 16 chalcone compounds were synthesized by Claisen-Schmidt condensation of various aldehydes with acetophenone using KOH as a base in ethanol. The reaction affords the desired products in good yields. Then all the 16 compounds were converted into pyrazoles by treating with hydrazine hydrate in ethanol under reflux condition. Both chalcones and pyrazoles were screened for their in vitro antibacterial (Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa) and antifungal (Aspergillus flavus, Chrysosporium keratinophilum and Candida albicans) activity. Biological activities of these compounds were compared with those of commercially available antibiotic ampicillin and antifungal agent miconazole. Pyrazoles were found to be most active and effective than corresponding chalcones for antimicrobial activity. Out of the 7 pyrazole compounds tested for antibacterial and antifungal activity, 5 compounds, 4h, 4j, 4l, 4m and 4n are turned out to be potent antimicrobial agents. Therefore these derivatives could serve as a highly promising molecules for further development.
Achieving Enantioselectivity in Difficult Cyclohexa-1,3-diene Diels-Alder Reactions with Sulfur-Stabilized Silicon Cations as Lewis Acid Catalysts
Shaykhutdinova, Polina,Oestreich, Martin
supporting information, p. 7029 - 7033 (2018/11/24)
A novel cationic silicon-sulfur Lewis pair with a chiral H8-binaphthyl backbone is reported. It catalyzes otherwise sluggish Diels-Alder reactions of cyclohexa-1,3-diene and chalcone derivatives in good yields and decent enantioselectivities (up to 81% ee). The enantioinduction is highest with a [1,1′-biphenyl]-4-yl substituent at the carbonyl carbon atom. This moiety can be later converted into a carboxyl group by Baeyer-Villiger oxidation. The same oxidant also epoxidizes the double bond in the cycloadduct, and the epoxide engages in a lactonization with the carboxylic acid. Synthetically interesting hexahydro-3,6-methanobenzofuran-2(3H)-one skeletons are obtained in one pot.
Silver-catalyzed decarboxylative cross-coupling of α-keto acids with alkenes giving approach to chalcones
Wu, Shang,Yu, Hongheng,Hu, Qinzheng,Yang, Quanlu,Xu, Shouwang,Liu, Tian
, p. 4763 - 4765 (2017/12/01)
A silver-catalyzed decarboxylative cross-coupling of α-keto acids with alkenes is reported. The method, with a wide range of substrate tolerance and mild operational conditions, can produce various chalcone derivatives in moderate to high yields from easily available starting materials.
Transition-Metal-Free Synthesis of Homo- and Hetero-1,2,4-Triaryl Benzenes by an Unexpected Base-Promoted Dearylative Pathway
Rehan, Mohammad,Maity, Sanjay,Morya, Lalit Kumar,Pal, Kaushik,Ghorai, Prasanta
supporting information, p. 7728 - 7732 (2016/07/07)
An unprecedented approach for the synthesis of homo- and hetero-1,2,4-triaryl benzenes has been developed using a simple base-mediated reaction of either α-aryl cinnamyl alcohols or α,γ-di-aryl propanones. The salient feature of this strategy involves the sequential hydride transfer, regiospecific condensation, regiospecific dearylation, and aromatization under metal-free reaction conditions. The synthesis of unsymmetrically substituted triphenylenes by oxidative coupling of the synthesized 1,2,4-triaryl benzenes has also been demonstrated.
Palladium-catalyzed decarboxylative arylation of benzoylacrylic acids toward the synthesis of chalcones
Unoh, Yuto,Hirano, Koji,Satoh, Tetsuya,Miura, Masahiro
, p. 5096 - 5102 (2013/07/05)
It has been found that readily available 3-benzoylacrylic acids undergo palladium-catalyzed decarboxylative arylation with arylboronic acids in the presence of a copper salt oxidant to produce chalcone derivatives. The decarboxylative arylation could also be achieved using aryl halides as the alternative aryl source to expand the applicable scope.
Stereoselective rearrangements with chiral hypervalent iodine reagents
Farid, Umar,Malmedy, Florence,Claveau, Romain,Albers, Lena,Wirth, Thomas
supporting information, p. 7018 - 7022 (2013/07/26)
I likes rearrangements: Hypervalent iodine compounds can be used as environmentally friendly, mild, and selective reagents for highly enantioselective rearrangements of alkenes. For the first time, rearrangements to α-arylated ketones can be performed enantioselectively using lactic acid-based iodine(III) reagents. Copyright
