N-Heterocyclic carbene-catalyzed stereoselective construction of olefinic carbon–sulfur bonds via cross-coupling reaction of gem-difluoroalkenes and thiols

2017 ◽  
Vol 15 (18) ◽  
pp. 3863-3868 ◽  
Author(s):  
Zi-Song Cong ◽  
Yang-Guo Li ◽  
Lei Chen ◽  
Fen Xing ◽  
Guang-Fen Du ◽  
...  
Keyword(s):  
Coupling Reaction ◽  
Cross Coupling ◽  
Olefinic Carbon ◽  
Bond Forming ◽  
Cross Coupling Reaction ◽  
Sulfur Bond

A novel organocatalytic olefinic carbon–sulfur bond forming reaction was developed.

scholarly journals Base-Free Suzuki–Miyaura Cross-Coupling Reaction Mediated by Lewis Acids

2021 ◽  
Author(s):  
Takashi Niwa ◽  
Yuta Uetake ◽  
Motoyuki Isoda ◽  
tadashi takimoto ◽  
Miki Nakaoka ◽  
...  
Keyword(s):  
Controlled Release ◽  
Lewis Acids ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Bond Forming ◽  
Carbon Carbon Bond ◽  
Cross Coupling Reaction ◽  
Theoretical Investigations ◽  
Active Intermediate ◽  
Palladium Catalyzed

The palladium-catalyzed Suzuki–Miyaura cross-coupling (SMC) reaction of organohalides and organoborons is a reliable carbon–carbon bond-forming method. This reaction involves a base-mediated transmetalation process, but the presence of a base also promotes competitive protodeborylation, which reduces the efficiency. Herein, we established a base-free SMC reaction via Lewis acid-mediated transmetalation of an organopalladium(II) intermediate with organoborons. Experimental and theoretical investigations indicate that the controlled release of the transmetalation-active intermediate enabled base-free transmetalation under heating conditions and enhanced the applicable scope of this process. This system enabled us to avoid the use of a base, and thus, rendered substrates with base-sensitive moieties available.

scholarly journals Base-Free Suzuki–Miyaura Cross-Coupling Reaction Mediated by Lewis Acids

2021 ◽  
Author(s):  
Takashi Niwa ◽  
Yuta Uetake ◽  
Motoyuki Isoda ◽  
tadashi takimoto ◽  
Miki Nakaoka ◽  
...  
Keyword(s):  
Controlled Release ◽  
Lewis Acids ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Bond Forming ◽  
Carbon Carbon Bond ◽  
Cross Coupling Reaction ◽  
Theoretical Investigations ◽  
Active Intermediate ◽  
Palladium Catalyzed

The palladium-catalyzed Suzuki–Miyaura cross-coupling (SMC) reaction of organohalides and organoborons is a reliable carbon–carbon bond-forming method. This reaction involves a base-mediated transmetalation process, but the presence of a base also promotes competitive protodeborylation, which reduces the efficiency. Herein, we established a base-free SMC reaction via Lewis acid-mediated transmetalation of an organopalladium(II) intermediate with organoborons. Experimental and theoretical investigations indicate that the controlled release of the transmetalation-active intermediate enabled base-free transmetalation under heating conditions and enhanced the applicable scope of this process. This system enabled us to avoid the use of a base, and thus, rendered substrates with base-sensitive moieties available.

Preparation of Aryl(dicyclohexyl)phosphines by C–P Bond-Forming Cross-Coupling in Water Catalyzed by an Amphiphilic-Resin-Supported Palladium Complex

Synlett ◽  
2017 ◽  
Vol 28 (20) ◽  
pp. 2966-2970 ◽  
Author(s):  
Yoshinori Hirai ◽  
Yasuhiro Uozumi
Keyword(s):  
Ethylene Glycol ◽  
Palladium Complex ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Phosphine Ligand ◽  
Poly Ethylene Glycol ◽  
Bond Forming ◽  
Cross Coupling Reaction ◽  
Supported Palladium ◽  
Poly Ethylene

Aryl(dicyclohexyl)phosphines were prepared by a catalytic C–P bond-forming cross-coupling reaction of haloarenes with dicyclohexylphosphine under heterogeneous conditions in water containing an immobilized palladium complex coordinated to an amphiphilic polystyrene–poly(ethylene glycol) resin supported di(tert-butyl)phosphine ligand.

Ferromagnetic Chain Based on Verdazyl-Nitroxide Diradical

2020 ◽  
Author(s):  
Evgeny Tretyakov ◽  
Svetlana Zhivetyeva ◽  
Pavel Petunin ◽  
Dmitry Gorbunov ◽  
Nina Gritsan ◽  
...  
Keyword(s):  
Coupling Reaction ◽  
Cross Coupling ◽  
Ferromagnetic Coupling ◽  
Nitronyl Nitroxide ◽  
Triplet Ground State ◽  
One Dimensional ◽  
Cross Coupling Reaction ◽  
Palladium Catalyzed ◽  
Ferromagnetic Chain ◽  
High Yields

<p>Verdazyl-nitroxide diradicals were synthesized using the palladium-catalyzed cross-coupling reaction of the corresponding iodoverdazyls with a nitronyl nitroxide-2-ide gold(I) complex with high yields (up to 82%). The synthesized diradicals were found to be highly thermally stable and have a singlet (D<i>E</i><sub>ST</sub> » -64 cm<sup>–1</sup>) or triplet ground state (D<i>E</i><sub>ST</sub> ³ 25 and 100 cm<sup>–1</sup>), depending on which canonical hydrocarbon diradical type they belong to. Upon crystallization, triplet diradicals form unique one-dimensional (1D) spin <i>S</i> = 1 chains of organic diradicals with intrachain ferromagnetic coupling of <i>J</i>′/<i>k</i><sub>B</sub> from 3 to 6 K.</p>

An Iron-Based Catalyst Enables The Enantioconvergent Synthesis of Chiral 1,1-Diarylalkanes Through a Suzuki-Miyaura Cross-Coupling Reaction

2020 ◽  
Author(s):  
Chet Tyrol ◽  
Nang Yone ◽  
Connor Gallin ◽  
Jeffery Byers
Keyword(s):  
Coupling Reaction ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Radical Intermediates ◽  
Cross Coupling Reactions ◽  
Cross Coupling Reaction ◽  
Boronic Esters ◽  
Carbon Centered Radical ◽  
Iron Based ◽  
High Yields

By using an iron-based catalyst, access to enantioenriched 1,1-diarylakanes was enabled through an enantioselective Suzuki-Miyaura crosscoupling reaction. The combination of a chiral cyanobis(oxazoline) ligand framework and 1,3,5-trimethoxybenzene additive were essential to afford high yields and enantioselectivities in cross-coupling reactions between unactivated aryl boronic esters and a variety of benzylic chlorides, including challenging ortho-substituted benzylic chloride substrates. Mechanistic investigations implicate a stereoconvergent pathway involving carbon-centered radical intermediates.

Ni(0)-Catalyzed α-Allylic Alkylation of Regular Ketones with 1,3-Dienes under pH and Redox-neutral Conditions

2019 ◽  
Author(s):  
Tiantian Chen ◽  
Yang Yang ◽  
Liyu Xie ◽  
Haijian Yang ◽  
Guangbin Dong ◽  
...  
Keyword(s):  
Oxidative Addition ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Dual Role ◽  
Allylic Alkylation ◽  
Cross Coupling Reaction ◽  
Neutral Conditions

<p>We report a Ni(0)-catalyzed cross coupling reaction between simple ketones and 1,3-dienes. A variety of a-allylic alkylation products were formed in an 1,2-addition manner with excellent regioselectivity. Water was found to significantly accelerate this transformation. A HO-Ni-H species generated from oxidative addition of Ni(0) to H<sub>2</sub>O is proposed to play a “dual role” in activating both the ketone and the diene substrate.</p>

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