99495-15-5Relevant articles and documents
Enantioselective Conjugate Addition of Stabilized Arylzinc Iodide to Enones: an Improved Protocol of the Hayashi Reaction
Casotti, Gianluca,Rositano, Vincenzo,Iuliano, Anna
, p. 1126 - 1131 (2020/12/17)
Stabilised arylzinc iodide, prepared by direct insertion of zinc into aryl iodides, were used as nucleophiles in the Hayashi Rh-catalysed enantioselective conjugate addition to enones. The reaction conditions were optimized in the addition of phenylzinc i
Synthesis of multinuclear Rh(I) complexes bearing triazolylidenes and their application in C-C and c-Si bond forming reactions
Mendoza-Espinosa, Daniel,Rendón-Nava, David,Vásquez-Pérez, Jose M.,Sandoval-Chávez, Cesar I.,Alvarez-Hernández, Alejandro
supporting information, p. 3961 - 3971 (2020/12/01)
Multidentate carbene ligands are valuable frameworks for the preparation of carbene complexes displaying higher nuclearity. In the present work, we report the synthesis of a series of mono- to tetra-[Rh(COD)I] complexes (3a- d) supported by mesoionic triazol-5-ylidenes. The general synthetic procedure involves the one step reaction of the appropriate triazolium (2a-d) salt in the presence of KHMDS and stoiquiometric amounts of the rhodium(I) precursor. Treatment of complexes 3a-d with an excess of carbon monoxide allows for the quantitative preparation of complexes 4a-d featuring a [Rh(CO)2I] fragment used for the detemination of the donor properties of the new triazolylidene ligands. All complexes have been fully characterized by means of 1H and 13C NMR spectroscopy, melting point, elemental analysis, and in the case of complex 3a, by X-ray crystallography. Comparison of the catalytic activity of the new rhodium complexes in C-C and C-Si bond forming processes demonstrate the enhanced performance of the tetranuclear species suggesting the possibility of strong cooperative effects in these multinuclear complexes.
The synthesis method of one-carbon ring expansion of cycloketone dericatives from β-selenyl cycloketone dericatives
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Paragraph 0041; 0044-0048; 0050-0054, (2020/09/08)
The present invention relates to a method for preparing a cyclic ketone derivative with an increased carbon number by performing a ring expansion reaction of a β-selenyl cyclic ketone derivative. The present invention was first developed by performing the
Rh-catalyzed 1,4-addition reactions of arylboronic acids accelerated by co-immobilized tertiary amine in silica mesopores
Motokura, Ken,Hashiguchi, Kohei,Maeda, Kyogo,Nambo, Masayuki,Manaka, Yuichi,Chun, Wang-Jae
, p. 1 - 9 (2019/05/04)
Mesoporous silica-supported Rh complex catalysts were prepared by simple silane-coupling, followed by complexation, and characterized by FT-IR, SEM, Rh K-edge XAFS, and elemental analysis. Local structures of the Rh complexes in each sample were almost similar to those of a nonporous silica-supported diaminorhodium complex. Co-immobilization of a tertiary amine on the same silica surface induced slight changes to the Rh complex structure in the case of the support with smaller pores. The prepared catalysts showed high activity for the 1,4-addition reaction of phenylboronic acids. Co-immobilization of the tertiary amine increased the reaction rate by more than 7-fold, with turnover number of nearly 8500. The catalytic performance achieved with this novel system is with much higher than that reported previously with a nonporous silica-supported catalyst. The mesoporous silica-supported Rh complex-tertiary amine showed a wide substrate scope, including unsaturated ketones and nitriles. This co-immobilized tertiary amine may activate phenylboronic acid to enhance its reactivity in the transmetalation step with Rh-OH species.
Anthranilamide (aam)-substituted arylboranes in direct carbon-carbon bond-forming reactions
Kamio, Shintaro,Kageyuki, Ikuo,Osaka, Itaru,Yoshida, Hiroto
supporting information, p. 2624 - 2627 (2019/03/05)
Anthranilamide (aam)-substituted arylboranes, which were reported to serve as masked boranes in the Suzuki-Miyaura coupling, have been found to be directly cross-coupled just by use of an aqueous medium. The excellent stability of 2-pyridyl-B(aam) toward protodeborylation allowed their smooth cross-coupling.
Electrochemical Radical Selenylation/1,2-Carbon Migration and Dowd-Beckwith-Type Ring-Expansion Sequences of Alkenylcyclobutanols
Kim, Yeon Joo,Kim, Dae Young
, p. 1021 - 1025 (2019/02/14)
Electrochemical oxidative radical selenylation/1,2-carbon migration and Dowd-Beckwith-type ring-expansion sequences of alkenylcyclobutanols were developed in this study. This approach is environmentally benign and uses shelf-stable diselenides as selenium
Synthesis of β-Selenylated Cyclopentanones via Photoredox-Catalyzed Selenylation/Ring-Expansion Cascades of Alkenyl Cyclobutanols
Jung, Hye Im,Kim, Dae Young
supporting information, p. 1361 - 1365 (2019/06/19)
A photoredox strategy to access β-selenated cyclic ketone derivatives through the coupling reaction of 1-(1-arylvinyl)cyclobutanols with diselenides under blue LED irradiation and an air atmosphere was developed. This reaction employs the easily accessibl
Palladium-catalyzed redox cascade for direct β-arylation of ketones
Huang, Zhongxing,Dong, Guangbin
supporting information, p. 3253 - 3265 (2018/05/04)
Herein we report a full article about the detailed design and development of two palladium-catalyzed redox cascade methods that enable direct β-arylation of ketones. Palladium-catalyzed ketone dehydrogenation, aryl-X bond activation and conjugate addition were merged into a redox-neutral catalytic cycle. Non-metal-based aryl electrophiles were used as both the oxidant and the aryl source. The β-arylation with aryl iodides was achieved site-selectively with Pd(TFA)2/P(i-Pr)3 as the precatalyst and AgTFA as the iodide scavenger. Both cyclic and linear ketones can react to give β-aryl ketones with excellent functional group tolerance. The β-arylation with diaryliodonium salts was realized without stoichiometric heavy metal additives, and proved to be redox-neutral. A wider substrate scope regarding aryl groups and ketones was obtained for the arylation with diaryliodonium salts, and the possible involvement of palladium nanoparticles as the active catalyst was examined and discussed.
Phosphine ligand compounds based on tetramethylspirobiindane skeleton, intermediate of compounds, and preparation method and application of compounds
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Paragraph 0166; 0167; 0168, (2018/11/03)
The invention discloses phosphine ligand compounds based on a tetramethylspirobiindane skeleton, an intermediate of the compounds, and a preparation method and application of the compounds. The phosphine ligand compounds are compounds having a structure r
Synthesis of Cyclohexanones through a Catalytic Cationic Cyclization of Alkynols or Enynes
Alonso, Pedro,Fontaneda, Raquel,Pardo, Pilar,Fa?anás, Francisco J.,Rodríguez, Félix
supporting information, p. 1659 - 1662 (2018/03/23)
A novel procedure for the synthesis of cyclohexanones from alkynol or enyne derivatives through a cationic cyclization has been developed. The key points to obtain the six-membered ring derivatives are the use of starting materials containing a terminal alkyne, the use of tetrafluoroboric acid as a promoter of the cationic cyclization, and the appropriate selection of 1,1,1,3,3,3-hexafluoropropan-2-ol (HFIP) as solvent. This strategy can be extended to the biomimetic cationic cyclization of several terpene-derived polyenynes.
