scholarly journals Protecting group-free, selective cross-coupling of alkyltrifluoroborates with borylated aryl bromides via photoredox/nickel dual catalysis

2015 ◽  
Vol 112 (39) ◽  
pp. 12026-12029 ◽  
Author(s):  
Yohei Yamashita ◽  
John C. Tellis ◽  
Gary A. Molander
Keyword(s):  
Small Molecules ◽  
Functional Group ◽  
Cross Coupling ◽  
Differential Protection ◽  
Coupling Reactions ◽  
Protecting Group ◽  
Cross Coupling Reactions ◽  
Aryl Bromides ◽  
Rapid Construction ◽  
Metal Catalyzed

Orthogonal reactivity modes offer substantial opportunities for rapid construction of complex small molecules. However, most strategies for imparting orthogonality to cross-coupling reactions rely on differential protection of reactive sites, greatly reducing both atom and step economies. Reported here is a strategy for orthogonal cross-coupling wherein a mechanistically distinct activation mode for transmetalation of sp3-hybridized organoboron reagents enables C-C bond formation in the presence of various protected and unprotected sp2-hybridized organoborons. This manifold has the potential for broad application, because orthogonality is inherent to the activation mode itself. The diversification potential of this platform is shown in the rapid elaboration of a trifunctional lynchpin through various transition metal-catalyzed processes without nonproductive deprotection or functional group manipulation steps.

scholarly journals Ligand-Controlled Regiodivergent Palladium-Catalyzed Hydrogermylation of Ynamides

2020 ◽  
Author(s):  
Vincent Debrauwer ◽  
Aneta Turlik ◽  
Lénaïc Rummler ◽  
Alessandro Prescimone ◽  
Nicolas Blanchard ◽  
...  
Keyword(s):  
Small Molecules ◽  
Functional Group ◽  
Cross Coupling ◽  
Building Blocks ◽  
Coupling Reactions ◽  
Heterocyclic Chemistry ◽  
Cross Coupling Reactions ◽  
Palladium Catalyzed ◽  
Metal Catalyzed ◽  
Pi System

Ynamides are fascinating small molecules with complementary reactivities under radical, ionic and metal-catalyzed conditions. We report herein synthetic and DFT investigations of palladium-catalyzed ligand-controlled regiodivergent hydro-metallation reactions of ynamides. Germylated and stannylated enamides are obtained with excellent alpha,<i>E</i>- or beta,<i>E</i>-selectivities and a broad functional group tolerance. Such a regiodivergent palladium-catalyzed process is unique in ynamide chemistry and allows for the elaboration of metallated-enamides that are useful building blocks for cross-coupling reactions or heterocyclic chemistry. DFT calculations fully support the experimental data and demonstrate the crucial roles of the <i>trans</i>-geometry of the [H-Pd(L)-Ge] complex, as well as of the steric requirements of the phosphine ligand. In addition, the prevalence of a hydro-palladation pathway over a metal-palladation of the pi system of the ynamide was demonstrated.

scholarly journals Ligand-Controlled Regiodivergent Palladium-Catalyzed Hydrogermylation of Ynamides

2020 ◽  
Author(s):  
Vincent Debrauwer ◽  
Aneta Turlik ◽  
Lénaïc Rummler ◽  
Alessandro Prescimone ◽  
Nicolas Blanchard ◽  
...  
Keyword(s):  
Small Molecules ◽  
Functional Group ◽  
Cross Coupling ◽  
Building Blocks ◽  
Coupling Reactions ◽  
Heterocyclic Chemistry ◽  
Cross Coupling Reactions ◽  
Palladium Catalyzed ◽  
Metal Catalyzed ◽  
Pi System

Ynamides are fascinating small molecules with complementary reactivities under radical, ionic and metal-catalyzed conditions. We report herein synthetic and DFT investigations of palladium-catalyzed ligand-controlled regiodivergent hydro-metallation reactions of ynamides. Germylated and stannylated enamides are obtained with excellent alpha,<i>E</i>- or beta,<i>E</i>-selectivities and a broad functional group tolerance. Such a regiodivergent palladium-catalyzed process is unique in ynamide chemistry and allows for the elaboration of metallated-enamides that are useful building blocks for cross-coupling reactions or heterocyclic chemistry. DFT calculations fully support the experimental data and demonstrate the crucial roles of the <i>trans</i>-geometry of the [H-Pd(L)-Ge] complex, as well as of the steric requirements of the phosphine ligand. In addition, the prevalence of a hydro-palladation pathway over a metal-palladation of the pi system of the ynamide was demonstrated.

Monodentate Trialkylphosphines: Privileged Ligands in Metal-catalyzed Crosscoupling Reactions

2020 ◽  
Vol 24 (3) ◽  
pp. 231-264 ◽  
Author(s):  
Kevin H. Shaughnessy
Keyword(s):  
Transition Metal ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Cross Coupling Reactions ◽  
Aryl Bromides ◽  
Wide Range ◽  
Sterically Demanding ◽  
Transition Metal Catalyzed ◽  
Catalyzed Reactions ◽  
Metal Catalyzed

Phosphines are widely used ligands in transition metal-catalyzed reactions. Arylphosphines, such as triphenylphosphine, were among the first phosphines to show broad utility in catalysis. Beginning in the late 1990s, sterically demanding and electronrich trialkylphosphines began to receive attention as supporting ligands. These ligands were found to be particularly effective at promoting oxidative addition in cross-coupling of aryl halides. With electron-rich, sterically demanding ligands, such as tri-tertbutylphosphine, coupling of aryl bromides could be achieved at room temperature. More importantly, the less reactive, but more broadly available, aryl chlorides became accessible substrates. Tri-tert-butylphosphine has become a privileged ligand that has found application in a wide range of late transition-metal catalyzed coupling reactions. This success has led to the use of numerous monodentate trialkylphosphines in cross-coupling reactions. This review will discuss the general properties and features of monodentate trialkylphosphines and their application in cross-coupling reactions of C–X and C–H bonds.

Directed ortho Metalation (DoM)-Linked Corriu–Kumada, Negishi, and Suzuki–Miyaura Cross-Coupling Protocols: A Comparative Study

Synthesis ◽  
2018 ◽  
Vol 50 (22) ◽  
pp. 4395-4412 ◽  
Author(s):  
Victor Snieckus ◽  
Claude Quesnelle
Keyword(s):  
Transition Metal ◽  
Comparative Study ◽  
Systematic Study ◽  
Functional Group ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Cross Coupling Reactions ◽  
Ortho Metalation ◽  
Transition Metal Catalyzed ◽  
Metal Catalyzed

A systematic study of the widely used, titled name reaction transition-metal-catalyzed cross-coupling reactions with attention to context with the directed ortho metalation (DoM) is reported. In general, the Suzuki–Miyaura and Negishi protocols show greater scope and better yields than the Corriu–Kumada variant, although the latter qualitatively proceeds at fastest rate but has low functional group tolerance. The Negishi process is shown to be useful for substrates with nucleophile and base-sensitive functionality and it is comparable to the Suzuki–Miyaura reaction in efficiency. The link of these cross-coupling reactions to the DoM strategy lends itself to the regioselective construction of diversely substituted aromatics and heteroaromatics.

Transition metal-catalyzed cross-coupling reactions using organoindium reagents

2017 ◽  
Vol 46 (3) ◽  
pp. 586-602 ◽  
Author(s):  
Kai Zhao ◽  
Liang Shen ◽  
Zhi-Liang Shen ◽  
Teck-Peng Loh
Keyword(s):  
Transition Metal ◽  
Functional Group ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Cross Coupling Reactions ◽  
Transition Metal Catalyzed ◽  
Metal Catalyzed

This review highlights the versatility and significance of transition metal-catalyzed cross-coupling reactions employing mild and unique organoindium reagents with exceptional functional group compatibility and sometimes remarkable chemo- and stereoselectivities.

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.

Synthesis of Marine Polyacetylenes Callyberynes A−C by Transition-Metal-Catalyzed Cross-Coupling Reactions to sp Centers

2006 ◽  
Vol 71 (7) ◽  
pp. 2802-2810 ◽  
Author(s):  
Susana López ◽  
Francisco Fernández-Trillo ◽  
Pilar Midón ◽  
Luis Castedo ◽  
Carlos Saá
Keyword(s):  
Transition Metal ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Cross Coupling Reactions ◽  
Transition Metal Catalyzed ◽  
Metal Catalyzed

scholarly journals Microwave-Enhanced Cross-Coupling Reactions Involving Alkynyltrifluoroborates with Aryl Bromides

Molecules ◽  
2013 ◽  
Vol 18 (2) ◽  
pp. 1755-1761 ◽  
Author(s):  
Vitali Coltuclu ◽  
Eric Dadush ◽  
Abhijit Naravane ◽  
George Kabalka
Keyword(s):  
Cross Coupling ◽  
Coupling Reactions ◽  
Cross Coupling Reactions ◽  
Aryl Bromides
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