Structural features and catalytic reactivity of [Pd{(Ph2P)2N(CH2)3Si(OCH3)3-κP,P′}I2] and related complexes in hydroalkoxycarbonylation and Suzuki–Miyaura C−C cross-coupling reactions

Polyhedron ◽  
2018 ◽  
Vol 151 ◽  
pp. 292-298 ◽  
Author(s):  
Ioannis K. Stamatopoulos ◽  
Maria Kapsi ◽  
Maria Roulia ◽  
Georgios C. Vougioukalakis ◽  
Catherine P. Raptopoulou ◽  
...  
2015 ◽  
Vol 68 (12) ◽  
pp. 1842 ◽  
Author(s):  
Sven S. Kampmann ◽  
Nikki Y. T. Man ◽  
Allan J. McKinley ◽  
George A. Koutsantonis ◽  
Scott G. Stewart

In this study, we present an investigation into various nickel phosphite and phosphite–phosphine complexes for use in the Mizoroki–Heck and Suzuki–Miyaura cross-coupling reactions and the ammonia arylation reaction. In these coupling reactions, it was discovered that the Ni[P(OEt)3]4, (dppf)Ni[P(OPh)3]2, and (binap)Ni[P(OPh)3]2 catalysts were the most effective. In addition, an optimisation process for these catalytic systems as well as functional group compatibility are discussed.


Molecules ◽  
2021 ◽  
Vol 26 (18) ◽  
pp. 5605
Author(s):  
Komal Rizwan ◽  
Nasir Rasool ◽  
Muhammad Ali Hashmi ◽  
Sadia Noreen ◽  
Muhammad Zubair ◽  
...  

A series of (E)-4-bromo-N-((3-bromothiophen-2-yl)methylene)-2-methylaniline analogs synthesized in considerable yields through Suzuki cross-coupling reactions. Various electron donating and withdrawing functional moieties were successfully incorporated under the employed reaction conditions. Reaction of 4-bromo-2-methylaniline (1) with 3-bromothiophene-2-carbaldehyde (2b) in the existence of glacial acetic acid, provided (E)-4-bromo-N-((3-bromothiophen-2-yl)methylene)-2-methylaniline (3b) in excellent yield (94%). Suzuki coupling of 3b with different boronic acids in the presence of Pd(PPh3)4/K3PO4 at 90 °C led to the synthesis of the monosubstituted and bisubstituted products 5a–5d and 6a–6d in moderate yields (33–40% and 31–46%, respectively). Density functional theory (DFT) investigations were performed on different synthesized analogues 5a–5d, 6a–6d to determine their structural characteristics. The calculations provide insight into the frontier molecular orbitals (FMOs) of the imine-based analogues and their molecular electrostatic potential (MESP). Reactivity descriptors like ionization energy (I), electron affinity (A), chemical hardness (ƞ) and index of nucleophilicity have been calculated for the first time for the synthesized molecules.


2020 ◽  
Author(s):  
Baojian Xiong ◽  
Yue Li ◽  
Yin Wei ◽  
Søren Kramer ◽  
Zhong Lian

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.


2020 ◽  
Author(s):  
Chet Tyrol ◽  
Nang Yone ◽  
Connor Gallin ◽  
Jeffery Byers

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.


2018 ◽  
Author(s):  
Yiming Zhao ◽  
Huy van Nguyen ◽  
Louise Male ◽  
Philip Craven ◽  
Benjamin R. Buckley ◽  
...  

<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>


2019 ◽  
Author(s):  
Victor Bloemendal ◽  
Floris P. J. T. Rutjes ◽  
Thomas J. Boltje ◽  
Daan Sondag ◽  
Hidde Elferink ◽  
...  

<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>


2019 ◽  
Author(s):  
Randolph Escobar ◽  
Jeffrey Johannes

<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>


2018 ◽  
Vol 22 (16) ◽  
pp. 1573-1588 ◽  
Author(s):  
Jannyely M. Neri ◽  
Andre H. de Oliveira ◽  
Renata M. Araujo ◽  
Livia N. Cavalcanti ◽  
Fabricio G. Menezes

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