6683-92-7Relevant academic research and scientific papers
Sulfonium ion-promoted traceless Schmidt reaction of alkyl azides
Ardiansah, Bayu,Kakiuchi, Kiyomi,Morimoto, Tsumoru,Tanimoto, Hiroki,Tomohiro, Takenori
, p. 8738 - 8741 (2021/09/08)
Schmidt reaction by sulfonium ions is described. General primary, secondary, and tertiary alkyl azides were converted to the corresponding carbonyl or imine compounds without any trace of the activators. This bond scission reaction through 1,2-migration of C-H and C-C bonds was accessible to the one-pot substitution reaction.
Asymmetric Catalytic Epoxidation of Terminal Enones for the Synthesis of Triazole Antifungal Agents
Feng, Xiaoming,He, Qianwen,Liu, Xiaohua,Zhang, Dong,Zhang, Fengcai
supporting information, p. 6961 - 6966 (2021/09/11)
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.
Rhodium-Catalyzed Deoxygenation and Borylation of Ketones: A Combined Experimental and Theoretical Investigation
Tao, Lei,Guo, Xueying,Li, Jie,Li, Ruoling,Lin, Zhenyang,Zhao, Wanxiang
supporting information, p. 18118 - 18127 (2020/11/26)
The rhodium-catalyzed deoxygenation and borylation of ketones with B2pin2 have been developed, leading to efficient formation of alkenes, vinylboronates, and vinyldiboronates. These reactions feature mild reaction conditions, a broad substrate scope, and excellent functional-group compatibility. Mechanistic studies support that the ketones initially undergo a Rh-catalyzed deoxygenation to give alkenes via boron enolate intermediates, and the subsequent Rh-catalyzed dehydrogenative borylation of alkenes leads to the formation of vinylboronates and diboration products, which is also supported by density functional theory calculations.
Ketone Synthesis from Benzyldiboronates and Esters: Leveraging α-Boryl Carbanions for Carbon-Carbon Bond Formation
Lee, Boran,Chirik, Paul J.
supporting information, p. 2429 - 2437 (2020/03/03)
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.
Coupling of Sulfoxonium Ylides with Arynes: A Direct Synthesis of Pro-Chiral Aryl Ketosulfoxonium Ylides and Its Application in the Preparation of α-Aryl Ketones
Talero, Alexánder Garay,Martins, Bruna Sim?es,Burtoloso, Antonio C. B.
supporting information, p. 7206 - 7211 (2018/11/23)
A general, mild, and versatile synthesis of the challenging α-aryl-β-ketosulfoxonium ylides has been developed for the first time, substituting traditional methods starting from diazo compounds. The arylation of easily accessible β-ketosulfoxonium ylides using aryne chemistry allowed the preparation of a large scope of the pro-chiral ylides in very good yields (40 examples; up to 85%). As applications, these ylides were smoothly converted into α-aryl ketones after desulfurization in good yields (up to 98%) as well as in other important derivatives.
Carbonylative Coupling of Alkyl Zinc Reagents with Benzyl Bromides Catalyzed by a Nickel/NN2 Pincer Ligand Complex
Andersen, Thomas L.,Donslund, Aske S.,Neumann, Karoline T.,Skrydstrup, Troels
supporting information, p. 800 - 804 (2017/12/26)
An efficient catalytic protocol for the three-component assembly of benzyl bromides, carbon monoxide, and alkyl zinc reagents to give benzyl alkyl ketones is described, and represents the first nickel-catalyzed carbonylative coupling of two sp3-carbon fragments. The method, which relies on the application of nickel complexed with an NN2-type pincer ligand and a controlled release of CO gas from a solid precursor, works well with a range of benzylic bromides. Mechanistic studies suggest the intermediacy of carbon-centered radicals.
Rational Design of a Metallocatalytic Cavitand for Regioselective Hydration of Specific Alkynes
Endo, Naoki,Inoue, Mami,Iwasawa, Tetsuo
supporting information, p. 1136 - 1140 (2018/03/13)
The synthesis of a functionalized supramolecular cavitand with inwardly oriented AuI and P=O moieties was explored, including its catalytic proclivity in the selective hydration of internal alkynes. The cavitand works as a supramolecular flask device: AuI coordinates to the triple bond, the P=O moiety connects with a H2O molecule, and the cavity favors folding of a single alkynyl side chain. Several tests of different substrate patterns indicated that the cavity was substrate specific, similar to enzymatic catalysis.
Selective Catalytic Hydration of Alkynes in the Presence of Au-Cavitands: A Study in Structure–Activity Relationships
Inoue, Mami,Ugawa, Katto,Maruyama, Tomoyuki,Iwasawa, Tetsuo
, p. 5304 - 5311 (2018/09/12)
The effects of the catalytic cavities in gold-functionalized cavitands in the hydration of internal alkynes have been studied. Variations on cavitand structures revealed the importance of two features that were studied: (1) flanking aromatic rings, and (2) an adjacent P=O moiety. The di-quinoxaline-spanned resorcin[4]arene system provides a well-defined compartment, in which a cationic Au ion activates an internal alkyne for conversion into a ketone by delivery of water that has also been activated, this time by a P=O moiety. We synthesized four variations on our parent cavitand. Variations of the cavitand walls include replacement of quinoxaline components with pyrazine or methylene units. Variation of the P=O center was accomplished with methylene or quinoxaline moieties. All variants displayed lower catalytic activity or selectivity, allowing us to confirm the significance both of an internal cavity and of an activation site for water.
A Remarkably Simple Hybrid Surfactant-NHC Ligand, Its Gold-Complex, and Application in Micellar Catalysis
Rühling, Andreas,Galla, Hans-Joachim,Glorius, Frank
supporting information, p. 12291 - 12294 (2015/08/25)
A combination of an N-heterocyclic carbene (NHC) ligand and a structurally simple surfactant has been realized, the hybrid surfactant-NHC. The related gold complex was synthesized, fully characterized, and applied in catalysis. This remarkably simple strategy allows, in combination with a co-surfactant, the application of gold catalysis in water. Just merge it! The hybrid of a surfactant and an N-heterocyclic carbene (NHC) ligand is reported and applied for the synthesis of the derived gold complex (see scheme). The new resulting NHC-based metallosurfactant can interact with surfactants to form micelles and allows micellar catalysis for gold catalysis in water.
Synthesis of β-haloketones by β-addition reactions of α,β-unsaturated ketones with BX3 (X = Br, Cl) as halide source
Lee, Adam Shih-Yuan,Wang, Shu-Huei,Chang, Yu-Ting
, p. 364 - 368 (2014/05/06)
A series of β-bromoketones and β-chloroketones were synthesized by the addition reactions of α,β-unsaturated ketones under BX 3 (X = Br, Cl) and ethylene glycol reaction system. The α,β-unsaturated ester also was successfully converted to its corresponding β-bromoester under the reaction condition. A series of β-bromoketones and β-chloroketones were synthesized by the addition reactions of α,β-unsaturated ketones under BX3 (X=Br, Cl) and ethylene glycol reaction system. Copyright
