Persistent Free Radicals from Low-Molecular-Weight Organic Compounds Enhance Cross-Coupling Reactions and Toxicity of Anthracene on Amorphous Silica Surfaces under Light

2021 ◽  
Vol 55 (6) ◽  
pp. 3716-3726
Author(s):  
Zhaoyue Sun ◽  
Xinghao Wang ◽  
Cun Liu ◽  
Guodong Fang ◽  
Longgang Chu ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Free Radicals ◽  
Organic Compounds ◽  
Amorphous Silica ◽  
Cross Coupling ◽  
Low Molecular Weight ◽  
Coupling Reactions ◽  
Silica Surfaces ◽  
Cross Coupling Reactions

scholarly journals Decarboxylative cross-coupling reactions for P(O)–C bond formation

RSC Advances ◽  
2018 ◽  
Vol 8 (46) ◽  
pp. 26383-26398 ◽  
Author(s):  
Akram Hosseinian ◽  
Fatemeh Alsadat Hosseini Nasab ◽  
Sheida Ahmadi ◽  
Zahra Rahmani ◽  
Esmail Vessally
Keyword(s):  
Organic Chemistry ◽  
Organic Compounds ◽  
Medicinal Chemistry ◽  
Bond Formation ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Materials Chemistry ◽  
Cross Coupling Reactions ◽  
Agricultural Chemistry ◽  
Phosphorus Containing

Phosphorus-containing compounds are one of the most important classes of organic compounds, which have wide applications in organic chemistry, medicinal chemistry, agricultural chemistry, and materials chemistry.

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.

Phosphino-Triazole Ligands for Palladium-Catalysed Cross-Coupling

2018 ◽  
Author(s):  
Yiming Zhao ◽  
Huy van Nguyen ◽  
Louise Male ◽  
Philip Craven ◽  
Benjamin R. Buckley ◽  
...  
Keyword(s):  
Drug Discovery ◽  
Cross Coupling ◽  
Product Formation ◽  
Coupling Reactions ◽  
Volume Determination ◽  
Online Tool ◽  
Triazole Derivatives ◽  
Cross Coupling Reactions ◽  
Modelling Approaches

<div>Twelve 1,5-disubtituted and fourteen 5-substituted 1,2,3-triazole derivatives bearing diaryl or dialkyl phosphines at the 5-position were synthesised and used as ligands for palladium-catalysed Suzuki-Miyaura cross-coupling reactions. Bulky substrates were tested, and lead-like product formation was demonstrated. The online tool SambVca 2.0 was used to assess steric parameters of ligands and preliminary buried volume determination using XRD obtained data in a small number of cases proved to be informative. Two modelling approaches were compared for the determination of</div><div>the buried volume of ligands where XRD data was not available. An approach with imposed steric restrictions was found to be superior in leading to buried volume determinations that closely correlate with observed reaction conversions. The online tool LLAMA was used to determine lead-likeness of potential Suzuki-Miyaura cross-coupling products, from which ten of the most lead-like were successfully synthesised. Thus, confirming these readily accessible triazole-containing phosphines as highly suitable ligands for reaction screening and optimisation in drug discovery campaigns.</div>

A Revised Modular Approach to D8-THC and Derivatives Through Late-Stage Suzuki-Miyaura Cross-Coupling Reactions

2019 ◽  
Author(s):  
Victor Bloemendal ◽  
Floris P. J. T. Rutjes ◽  
Thomas J. Boltje ◽  
Daan Sondag ◽  
Hidde Elferink ◽  
...  
Keyword(s):  
Biological Activity ◽  
Late Stage ◽  
Medicinal Chemistry ◽  
Cross Coupling ◽  
Modular Approach ◽  
Coupling Reactions ◽  
One Pot ◽  
Biologically Relevant ◽  
Cross Coupling Reactions ◽  
Chemistry Research

<p>In this manuscript we describe a modular pathway to synthesize biologically relevant (–)-<i>trans</i>-Δ<sup>8</sup>-THC derivatives, which can be used to modulate the pharmacologically important CB<sub>1</sub> and CB<sub>2</sub> receptors. This pathway involves a one-pot Friedel-Crafts alkylation/cyclization protocol, followed by Suzuki-Miyaura cross-coupling reactions and gives rise to a series of new Δ<sup>8</sup>-THC derivatives. In addition, we demonstrate using extensive NMR evidence that similar halide-substituted Friedel-Crafts alkylation/cyclization products in previous articles were wrongly assigned as the para-isomers, which also has consequence for the assignment of the subsequent cross-coupled products and interpretation of their biological activity. </p> <p>Considering the importance of the availability of THC derivatives in medicinal chemistry research and the fact that previously synthesized compounds were wrongly assigned, we feel this research is describing a straightforward pathway into new cannabinoids.</p>

Carbon-Heteroatom Cross-Coupling via an Electronically Excited Nickel (II) Complex

2019 ◽  
Author(s):  
Randolph Escobar ◽  
Jeffrey Johannes
Keyword(s):  
Energy Transfer ◽  
Functional Groups ◽  
Cross Coupling ◽  
Reductive Elimination ◽  
Aryl Halides ◽  
Coupling Reactions ◽  
General Methodology ◽  
Cross Coupling Reactions ◽  
Electronically Excited ◽  
Energy Transfer Pathway

<div>While carbon-heteroatom cross coupling reactions have been extensively studied, many methods are specific and</div><div>limited to a set of substrates or functional groups. Reported here is a method that allows for C-O, C-N and C-S cross coupling reactions under one general methodology. We propose that an energy transfer pathway, in which an iridium photosensitizer produces an excited nickel (II) complex, is responsible for the key reductive elimination step that couples aryl halides to 1° and 2° alcohols, anilines, thiophenols, carbamates and sulfonamides.</div>

Sign in / Sign up

Export Citation Format

Share Document