102692-33-1Relevant articles and documents
Ligand and substrate π-stacking interaction controlled enantioselectivity in the asymmetric aziridination
Ma, Linge,Jiao, Peng,Zhang, Qihan,Du, Da-Ming,Xu, Jiaxi
, p. 878 - 884 (2007)
Both the steric hindrance and the electronic effect are important factors for controlling the enantioselectivity in asymmetric catalysis. The substituent-dependent enantioselectivity in the asymmetric aziridination of chalcones catalyzed by 1,8-anthracene
Enantioselective Diels-Alder Reactions of Cyclohexa-1,3-diene and Chalcones Catalyzed by Intramolecular Silicon-Sulfur Lewis Pairs as Chiral Lewis Acids
Shaykhutdinova, Polina,Oestreich, Martin
, p. 2768 - 2771 (2016)
The stereoselective preparation of diastereomeric dihydrosilepine-derived silicon cations decorated with another binaphthyl unit at the silicon atom is described. A sulfide donor attached to that additional binaphthyl substituent forms an intramolecular Lewis pair with the electron-deficient silicon atom, as verified by 29Si NMR spectroscopy. Both chiral sulfur-stabilized silicon cations act as catalysts in the difficult Diels-Alder reaction of cyclohexa-1,3-diene and chalcone derivatives. Both Lewis acids induce enantioselectivity, but the S,S relative configuration is superior to the S,R configuration. With the former diastereomer, enantiomeric excesses of close to 60% are obtained. These values are the highest achieved to date in this seemingly trivial cycloaddition.
Palladium-imidazolium-catalyzed carbonylative coupling of aryl diazonium ions and aryl boronic acids
Andrus, Merritt B.,Ma, Yudao,Zang, Yunfu,Song, Chun
, p. 9137 - 9140 (2002)
Palladium(II) acetate and N,N-bis-(2,6-diisopropylphenyl)dihydroimidazolium chloride (2 mol%) were used to catalyze the carbonylative coupling of aryl diazonium tetrafluoroborate salts and aryl boronic acids to form aryl ketones. Optimal conditions includ
Green method for high-selectivity synthesis of chalcone compounds
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Paragraph 0051-0054, (2021/10/02)
Under the condition of air, the water-soluble inorganic weak base is used as a catalyst to catalyze the hydrogen transfer reaction of the propargyl alcohol compound, so that the green synthesis of the high-trans selective chalcone compound is realized. Reaction temperature: 80 - 120 °C and reaction time 12 - 48 hours. To the technical scheme, any transition metal catalyst and ligand do not need to be used, inert gas protection is not needed, no other byproducts are generated, the atom economy 100%, green and environment friendliness are avoided, and the product is a high-selectivity (E)-type product. The reaction conditions are relatively low in requirement. Compared with the prior art, the alkali catalyst is obvious in advantages, and has a certain application prospect in the fields of organic synthesis, biochemistry, medicine and the like.
DBU-Catalyzed Rearrangement of Secondary Propargylic Alcohols: An Efficient and Cost-Effective Route to Chalcone Derivatives
De, Rimpa,Savarimuthu, Antony,Ballav, Tamal,Singh, Pijush,Nanda, Jayanta,Hasija, Avantika,Chopra, Deepak,Bera, Mrinal K.
supporting information, p. 1587 - 1592 (2020/08/28)
A 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)-catalyzed rearrangement of diarylated secondary propargylic alcohols to give α,β-unsaturated carbonyl compounds has been developed. The typical 1,3-transposition of oxy functionality, characteristic of Mayer-Schuster rearrangements, is not observed in this case. A broad substrate scope, functional-group tolerance, operational simplicity, complete atom economy, and excellent yields are among the prominent features of the reaction. Additionally, the photophysical properties and crystal-structure-packing behavior of selected compounds were investigated and found to be of interest.
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.
Visible Light Activated Radical Denitrative Benzoylation of β-Nitrostyrenes: A Photocatalytic Approach to Chalcones
Tripathi, Shubhangi,Kapoor, Ritu,Yadav, Lal Dhar S.
supporting information, p. 1407 - 1413 (2018/04/10)
A metal-free, convenient photocatalytic approach to chalcones from β-nitrostyrenes and benzaldehydes via a radical denitrative benzoylation pathway is reported. The salient features of the protocol include the utilization of visible light as an inexpensive and ecosustainable energy source, N-hydroxyphthalimide (NHPI) as a reusable organophotocatalyst and acetonitrile as an acceptable green solvent to afford chalcones in excellent yields at room temperature in a one-pot procedure. Notably, this is the first application of β-nitrostyrenes as readily available substrates for chalcone synthesis and the first example of photocatalysis in this field. (Figure presented.).
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.
Continuous-flow hydration-condensation reaction: Synthesis of αβ-unsaturated ketones from alkynes and aldehydes by using a heterogeneous solid acid catalyst
Rueping, Magnus,Bootwicha, Teerawut,Baars, Hannah,Sugiono, Erli
supporting information; experimental part, p. 1680 - 1687 (2012/02/04)
A simple, practical and efficient continuous-flow hydration-condensation protocol was developed for the synthesis of α,β-unsaturated ketones starting from alkynes and aldehydes by employing a heterogeneous catalyst in a flow microwave. The procedure presents a straightforward and convenient access to valuable differently substituted chalcones and can be applied on multigram scale.
Carbonylative heck reactions using CO generated ex situ in a two-chamber System
Hermange, Philippe,Gogsig, Thomas M.,Lindhardt, Anders T.,Taaning, Rolf H.,Skrydstrup, Troels
supporting information; experimental part, p. 2444 - 2447 (2011/07/09)
Chemical equations presented. A carbonylative Heck reaction of aryl iodides and styrene derivatives employing a two-chamber system using a stable, crystalline, and nontransition metal based carbon monoxide source is reported. By applying near-stoichiometr
