Coupling Reactions of Bromoalkynes with Imidazoles Mediated by Copper Salts: Synthesis of NovelN-Alkynylimidazoles

2008 ◽  
Vol 73 (16) ◽  
pp. 6462-6465 ◽  
Author(s):  
Christophe Laroche ◽  
Jing Li ◽  
Matthew W. Freyer ◽  
Sean M. Kerwin
Keyword(s):  
Coupling Reactions ◽  
Copper Salts

ChemInform Abstract: Coupling Reactions of Bromoalkynes with Imidazoles Mediated by Copper Salts: Synthesis of Novel N-Alkynylimidazoles.

ChemInform ◽  
2009 ◽  
Vol 40 (1) ◽  
Author(s):  
Christophe Laroche ◽  
Jing Li ◽  
Matthew W. Freyer ◽  
Sean M. Kerwin
Keyword(s):  
Coupling Reactions ◽  
Copper Salts

scholarly journals The effects of amines on oxidative homo-coupling of terminal alkynes promoted by copper salts

2005 ◽  
Vol 2005 (2) ◽  
pp. 112-115 ◽  
Author(s):  
Lei Wang ◽  
Jincan Yan ◽  
Pinhua Li ◽  
Min Wang ◽  
Caina Su
Keyword(s):  
Reaction Medium ◽  
Cross Coupling ◽  
Catalytic Amount ◽  
Sonogashira Reaction ◽  
Coupling Reactions ◽  
Sonogashira Coupling ◽  
Terminal Alkynes ◽  
Copper Salts ◽  
Terminal Acetylenes ◽  
Glaser Coupling

The effects of all kinds of amines on homo-couplings (Glaser reactions) of terminal alkynes promoted by copper salts and the Sonogashira coupling reactions were studied systematically. Diethylamine (2° amine) can serve as an excellent solvent, base and coordination ligand in the oxidative homo-coupling of terminal alkynes and several modified Glaser coupling procedures have been developed which are based on a catalytic amount of cuprous salts (CuI, CuBr or CuCl) with diethylamine systems. Homo-coupling of terminal acetylenes in the Sonogashira reaction could be inhibited by using triethylamine (3° amine) as reaction medium, and the cross-coupling products were formed as the exclusive products.

Evaluation of catalytic activity of copper salts and their removal processes in the three-component coupling reactions

2008 ◽  
Vol 80 (5) ◽  
pp. 873-879 ◽  
Author(s):  
Seung Jun Hwang ◽  
Seung Hwan Cho ◽  
Sukbok Chang
Keyword(s):  
Catalytic Activity ◽  
Coupling Reaction ◽  
Coupling Reactions ◽  
Terminal Alkynes ◽  
Ligand Effect ◽  
Copper Salts ◽  
Wide Range ◽  
Sulfonyl Azides ◽  
Removal Processes ◽  
Three Component Coupling

The catalytic activity of a wide range of copper salts, including Cu(I) and Cu(II), has been examined in the Cu-catalyzed three-component coupling reactions of sulfonyl azides, terminal alkynes, and amines, alcohols, or water to afford N-sulfonyl amidines, imidates, and amides, respectively. Furthermore, the investigation on the ligand effect in our protocol has revealed that certain types of ligands such as tris(benzyltriazolylmethyl)amine (TBTA) exhibited notable acceleration effects on the coupling reaction. The facile and efficient methods for removing copper salts from reaction mixture were also examined.

Dual Nickel/Palladium-Catalyzed Reductive Cross-Coupling Reactions Between Two Phenol Derivatives

2020 ◽  
Author(s):  
Baojian Xiong ◽  
Yue Li ◽  
Yin Wei ◽  
Søren Kramer ◽  
Zhong Lian
Keyword(s):  
Functional Group ◽  
Low Cost ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Phenol Derivatives ◽  
Cross Coupling Reactions ◽  
Palladium Catalyzed ◽  
One Step ◽  
Aryl Tosylates ◽  
Low Sensitivity

Cross-coupling between substrates that can be easily derived from phenols is highly attractive due to the abundance and low cost of phenols. Here, we report a dual nickel/palladium-catalyzed reductive cross-coupling between aryl tosylates and aryl triflates; both substrates can be accessed in just one step from readily available phenols. The reaction has a broad functional group tolerance and substrate scope (>60 examples). Furthermore, it displays low sensitivity to steric effects demonstrated by the synthesis of a 2,2’disubstituted biaryl and a fully substituted aryl product. The widespread presence of phenols in natural products and pharmaceuticals allow for straightforward late-stage functionalization, illustrated with examples such as Ezetimibe and tyrosine. NMR spectroscopy and DFT calculations indicate that the nickel catalyst is responsible for activating the aryl triflate, while the palladium catalyst preferentially reacts with the aryl tosylate.

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.

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