Suzuki Coupling Research Articles

Facile Fabrication of LaFeO 3 Supported Pd Nanoparticles as Highly Effective Heterogeneous Catalyst for Suzuki–Miyaura Coupling Reaction

Supported Pd catalysts have been widely studied due to their enormous potential as candidates for heterogeneous Suzuki–Miyaura coupling reactions. However, the sintering and low activity of active sites still remain challenges. A vesicle‐shaped LaFeO3‐supported Pd catalyst (I‐Pd/LaFeO3) was successfully fabricated using the impregnation method and tested for the Suzuki–Miyaura coupling reaction. Compared to P‐Pd/LaFeO3 prepared with photo‐deposition and Pd/Al2O3 prepared with impregnation, the I‐Pd/LaFeO3 catalyst exhibits significantly higher catalytic activity, stability, and reusability. The chemical composition and electron states of different Pd‐based catalysts were well studied based on various characterizations and the results indicated that the excellent performance of I‐Pd/LaFeO3 can be attributed to its unique nanostructure and the strong interactions between LaFeO3 and palladium nanoparticles. The impregnation method and the choice of the LaFeO3 support show a great influence on the electronic properties of Pd species, their reducibility, and, consequently, their reaction behavior. This unique LaFeO3 supported Pd catalyst provided an environmentally friendly heterogeneous method for the Suzuki–Miyaura coupling reaction.

Divergent Total Synthesis of Isoflavone Natural Products and Their Potential as Therapeutic Agents for TTR Amyloidosis.

We have achieved the divergent total synthesis of nine isoflavone natural products 1-9 starting from commercially available 2,4,6-trihydroxyacetophenone as a starting material. The isoflavone skeleton of 1-9 was constructed by the Suzuki-Miyaura coupling reaction as the key reaction. Investigation of the potential of 1-9 as therapeutic agents for transthyretin (TTR) amyloidosis revealed that millexatin F (3) showed the best efficacy in ex vivo competitive binding experiments and thioflavin-T fluorescence studies. Therefore, millexatin F (3) is promising as a seed compound for a novel TTR amyloidosis therapeutic agent.

Conjugated Polymers Based on Carbazole and Tridentate Ligands as the "On-Off-On" Fluorescent Probes for Detection of Ni (II) Ion and Lysine.

Two novel conjugated polymers (polymer 1 and polymer 2) containing trisheterocyclic systemsand carbazole as the copolymerization unit were synthesized by the Suzuki coupling reaction and characterized using NMR spectroscopy and other methods. 4'-(3,5-Dibromophenyl)-2,2':6',2''-terpyridine and 2,2'-(4-(3,5-dibromophenyl)pyridine-2,6-diyl)dithiazole were used as the recognizing units of the two polymers respectively. The polymers show blue-violet fluorescence when dissolved in THF. The ability of the polymers to identify anions and metal ions was investigated by fluorescence sensing tests. It was found that I- not only quenched the fluorescence but also undergone some redshift. Ni (II) efficiently quenched the fluorescence of the polymers, and polymer 2 recognized Ni2+ with higher specificity. UV-visible absorption titration experiments showed that Ni2+ formed complexes with the polymers. In addition, the formation of complexes between Ni2+ and polymers were used for the detection of amino acids, and it was found that lysine could regenerate the fluorescence of [polymer 1-Ni2+] and [polymer 2-Ni2+] with 99% fluorescence recovery.

Nickel Catalyzed Aryl-Aryl Bridging C-N Bond Activation of 2-Pyridylpyridones and 6-Purinylpyridones.

A Ni-catalyzed C-N bond activation of 2-pyridylpyridone and 1-(9-alkyl 9H-purin-6-yl)pyridin-2(1H)-one and coupling with arylboronic acid have been achieved. A unique feature of this reaction is the strategic activation of the bridging C-N bond and replacement of the pyridone unit with aryl groups using nickel catalyzed Suzuki-Miyaura coupling. This provides an exciting new tool to build C-C bonds in the place of pyridones. A wide variety of substrates and boronic acids are amenable to this transformation. More importantly, we have successfully synthesized a variety of C(6)-arylated purines via deaminative cross-coupling which are very useful in developing unnatural nucleobases, nucleotides, and nucleosides.

Post-synthetic sulfonation of resorcinarene-based porous organic polymer for superfast adsorption of diverse organic pollutants

A resorcinarene-based porous organic polymer was synthesized via the Suzuki–Miyaura coupling reaction and then functionalized by chlorosulfonic acid to obtain a sulfonated product named BaPy-SO3H. Characterization results indicate that BaPy-SO3H has porous skeletons, excellent thermal stability, and electronegative surface charges. Remarkably, BaPy-SO3H exhibits superfast rates and reaches adsorption equilibrium within 1 min towards diverse organic pollutants including dyes, herbicides, and antibiotics via electrostatic interactions, π–π interactions, and host–guest effects. Especially for Crystal Violet, Malachite Green, and Paraquat, BaPy-SO3H achieves apparent rate constants for a pseudo-second-order model of 31.24, 31.27, and 30.63 g mg−1 min−1, respectively, which are the highest values among reported adsorbents to the best of our knowledge. Meanwhile, the maximum adsorption capacity of BaPy-SO3H reaches 1850 mg g−1 for Rhodamine B, 2295 mg g−1 for Methyl Blue, 1503 mg g−1 for Crystal Violet, and 1304 mg g−1 for trimethoprim, surpassing most of the adsorbents reported so far. The above results demonstrate the superior adsorption performance of BaPy-SO3H towards diverse organic pollutants and its potential applications in real-water scenarios.

Pd EnCat™ 30 Recycling in Suzuki Cross-Coupling Reactions

Pd EnCat™ 30 is a palladium catalyst broadly used in several hydrogenation and cross-coupling reactions. It is known for its numerous beneficial features, which include high-yielding performance, easy recovery, and reusability. However, the available data regarding its recyclability in Suzuki coupling reactions are limited to a few reaction cycles and, therefore, fail to explore its full potential. Our work focuses on investigating the extent of Pd EnCat™ 30 reusability in Suzuki cross-coupling reactions by measuring its performance according to isolated yields of product. Our findings demonstrate that Pd EnCat™ 30 can be reused over a minimum of 30 reaction cycles, which is advantageous in terms of cost reduction and more sustainable chemical production.

5]Helicene Based π-Conjugated Macrocycles with Persistent Figure-Eight and Möbius Shapes: Efficient Synthesis, Chiral Resolution and Bright Circularly Polarized Luminescence.

π-Conjugated chiral shape-persistent molecular nanocarbons hold great potential as chiroptical materials, though their synthesis remains a considerable challenge. Here, we present a simple approach using Suzuki coupling of a [5]helicene building block with various aromatic units, enabling the one-pot synthesis of a series of chiral macrocycles with persistent figure-eight and Möbius shapes. Single-crystal structures of 7 compounds were solved, and 22 enantiomers were separated by preparative chiral HPLC. A notable pyrene-bridged figure-eight macrocycle, with its rigid, fully π-conjugated and overcrowded structure, exhibited pure excimer emission and outstanding circularly polarized luminescence (CPL) properties, including a large dissymmetric factor (|glum| = 3.8 × 10-2) and significant CPL brightness (BCPL = 710.5 M-1cm-1). This method provides a versatile synthetic platform for producing various chiral D2-symmetric figure-eight macrocycles and singly or triply twisted Möbius macrocycles with C2 and D3 symmetry, offering tunable chiroptical properties for CPL applications.

5]Helicene Based π‐Conjugated Macrocycles with Persistent Figure‐Eight and Möbius Shapes: Efficient Synthesis, Chiral Resolution and Bright Circularly Polarized Luminescence

π‐Conjugated chiral shape‐persistent molecular nanocarbons hold great potential as chiroptical materials, though their synthesis remains a considerable challenge. Here, we present a simple approach using Suzuki coupling of a [5]helicene building block with various aromatic units, enabling the one‐pot synthesis of a series of chiral macrocycles with persistent figure‐eight and Möbius shapes. Single‐crystal structures of 7 compounds were solved, and 22 enantiomers were separated by preparative chiral HPLC. A notable pyrene‐bridged figure‐eight macrocycle, with its rigid, fully π‐conjugated and overcrowded structure, exhibited pure excimer emission and outstanding circularly polarized luminescence (CPL) properties, including a large dissymmetric factor (|glum| = 3.8 × 10−2) and significant CPL brightness (BCPL = 710.5 M‐1cm‐1). This method provides a versatile synthetic platform for producing various chiral D2‐symmetric figure‐eight macrocycles and singly or triply twisted Möbius macrocycles with C2 and D3 symmetry, offering tunable chiroptical properties for CPL applications.

Recent Updates on Pd‐Incorporated Ionic Liquids Catalyzed Suzuki Cross‐Coupling Reaction: A Mini‐Review

ABSTRACTIonic liquids (ILs) have been recognized for their potential as environmentally friendly solvents when compared to traditional organic solvents. Additionally, their function goes beyond that of solvents, and cocatalysts, as they frequently act as stabilizing agents and ligands for the metal‐active species and intermediates in catalytic systems. This comprehensive review primarily focuses on the application of Pd‐incorporated ILs in catalyzing cross‐coupling Suzuki reactions. The responses play a vital role in creating a wide range of structurally diverse and highly functionalized organic compounds, focusing specifically on nucleopalladation Suzuki coupling reactions. The review provides a detailed summary of the reaction conditions, stereoselectivity and regioselectivity, and the underlying mechanisms. Furthermore, it underscores crucial and characteristic illustrations, displaying the practical implementations of these coupling reactions. The aim of this review is to stimulate further research efforts, with the ultimate goal of expanding our understanding and utilization of ILs in various fields in the future.

Heteroaryl Group Containing Trisubstituted Alkenes: Synthesis and Anti-tumor Activity.

Pancreatobililary cancers are fatal solid tumors that pose a significant threat to human life. It is imperative to investigate novel small molecule active compounds for controlling these cancers. Heterocyclic compounds (e. g. gemcitabine) and multi-substituted alkenes (e. g. resveratrol) are commonly applied in tumor treatment. Researchers have proposed that the synthesis of new trisubstituted alkenes containing heteroaromatic rings by combining these two scaffolds may be a fresh strategy to develop new active molecules. In this study, we utilized alkenyl bromide and heteroaryl boronic acid as substrates, employing Suzuki coupling to generate a series of triarylethylenes featuring nitrogen, oxygen, and sulfur atoms. Through in vitro experiments, the results indicated that some compounds exhibited remarkable anti-tumor efficacy (e. g. IC50[3be, GBC-SD]=0.13 μM and IC50[3be, PANC-1]=0.27 μM). The results further demonstrated that the antitumor efficacy of these compounds was dependent on the heteroatom, π-system, skeleton-bonding site, and substituent type.

Gold‐Catalyzed Heck and Suzuki‐Type Reactions: Challenges and Recent Advances

AbstractTransition metal‐catalyzed Suzuki and Heck reactions are two of the most common carbon‐carbon bond formation reactions. Gold, unlike other transition metals (Pd, Ni, and Cu), offers unique reactivity profiles, and has emerged as an efficient tool in the field of synthetic organic chemistry. This mini‐review focused on the recent work in gold‐catalyzed Heck and Suzuki‐type reactions, especially by photocatalysts or ligand design, which show reactivities and features distinct from other transition metals. These discoveries will further facilitate the development of gold redox catalysis as well as applications in organic synthesis, biochemistry, and medicinal chemistry.

The iron-catalysed Suzuki coupling of aryl chlorides

The iron-catalysed Suzuki coupling of aryl chlorides

Site Effect of Electron Acceptors on Ultralong Organic Room-Temperature Phosphorescence.

Herein, we successfully observe the site effect of electron acceptors on ultralong organic room-temperature phosphorescence (UORTP) in the case of 7H-benzo[c]carbazole (BCz) derivatives: cyanophenyl on the nitrogen site can promote intersystem crossing (ISC) efficiency and enhance phosphorescence intensity by facilitating n-π* transitions but make a slight change to the phosphorescence wavelength; cyanophenyl on the naphthalene site can cause a remarkable red shift of phosphorescence wavelength by reducing the T1 energy level of BCz derivatives and also enhance phosphorescence intensity by promoting ISC but weaken phosphorescence intensity by lowering the molecular symmetry. Three BCz derivatives (1-BCzPhCN, 2-BCzPhCN, and 3-BCzPhCN) with the electron acceptor cyanophenyl at different sites (nitrogen site and naphthalene site) were synthesized through a combination of the nucleophilic substitution reaction and the Suzuki coupling reaction. The phosphorescence properties of 1-BCzPhCN, 2-BCzPhCN, and 3-BCzPhCN in toluene solution, in a copolymerized MMA film, and in a PVA film were measured and analyzed. 1-BCzPhCN emits intrinsic green ultralong phosphorescence at ∼500, ∼536, and ∼580 nm, while 2-BCzPhCN and 3-BCzPhCN give out intrinsic yellow ultralong phosphorescence with a red shift of 27 and 40 nm, showing that cyanophenyl on the naphthalene site leads to a remarkable red shift of the intrinsic phosphorescence wavelength, but cyanophenyl on the nitrogen site makes a slight difference to the intrinsic phosphorescence wavelength. Under the same condition, the phosphorescence intensity is usually ranked as 1-BCzPhCN/3-BCzPhCN > 2-BCzPhCN, demonstrating that cyanophenyl on the nitrogen site promotes ISC and enhances phosphorescence intensity, but cyanophenyl on the naphthalene site reduces molecular symmetry and accelerates nonradiative dissipation. Time-dependent density functional theory calculations verify that cyanophenyl on the naphthalene site shifts the phosphorescence wavelength by reducing the T1 energy level, and cyanophenyl on the nitrogen site facilitates n-π* transitions to strengthen the phosphorescence intensity. Moreover, three BCz derivatives were doped into DMAP and BBP, separately. The BCz derivatives exhibited different phosphorescence colors and shifts due to interactions with the host materials. We believe this work will give an insight into the structure-property relationship of organic phosphorescence molecules and pave a way for design of colorful UORTP materials.

Recyclable polyethylenimine based polymer for selective Pd(II) recovery and Suzuki reaction: Waste to treasure tactics

Developing efficient materials for the selective capture of Pd(II) from secondary sources, along with the reutilization of spent Pd(II)-loaded adsorbents, is of great significance, but remains great challenging. Herein, a highly efficient adsorbent (TP@PEI) was fabricated through polycondensation of polyethyleneimine (PEI) with 1,3,5-triformylphoroglucinol (TP), which selectively extracts palladium ions from simulated industrial wastewater, with preferential uptake of Pd(II) over 9 competing cations. The TP@PEI achieves ultrafast capture of Pd(II) in just 20 min, with an impressive adsorption capacity of 620 mg g−1. Of greater significance, the removal efficiency for Pd(II) reaches 99.9 % at a concentration of 100 mg L-1, which still remains at a remarkable 99 % after 11 adsorption–desorption cycles. Exceptional 99.9 % Pd(II) recovery is achieved through the adsorption of a depleted Pd-digested solution, while the breakthrough test validates its practicality and impressive bed breakthrough time (1070 min). Mechanism study reveals that the exceptional adsorption performance of TP@PEI for palladium is driven by synergistic interactions, including coordination and electrostatic interactions. Furthermore, the waste Pd(II) loaded TP@PEI efficiently catalyzes the Suzuki reaction in water, achieving a remarkable 99 % yield of the targeted compound. This research showcases a strategy for converting industrial waste into a valuable resource by meticulously engineering materials to extract precious metals from wastewater, subsequently repurposing them as high-performing catalysts.

Pd-Catalyzed C(sp2)-C(sp3) Suzuki Coupling and Synthesis of Lumacaftor Using Designed Monophosphine Ligands.

Novel monophosphine ligands L1 and L2 with a C-P ring were designed and synthesized for the efficient Pd-catalyzed C(sp2)-C(sp3) Suzuki coupling. With 0.5 mol % Pd2dba3 and 2 mol % L1, aryl halides coupled with alkylboronic acids to give the products in up to 99% yield. The aryl thianthrene salt was further applied for late-stage methylation in 97% yield. The active pharmaceutical ingredient lumacaftor was synthesized by aryl-alkyl and aryl-aryl Suzuki coupling reactions using L1 and L2.

Cyclization by Intramolecular Suzuki-Miyaura Cross-Coupling - A Review.

Ring systems of all sizes are frequent core or substructures in natural products and they are important elements of many drug molecules, as they often confer high binding affinity to and selectivity for disease-relevant biological targets. A uniform key transformation in the synthesis of such structures is the cyclization step. Among the various approaches that have been developed for ring closure, the intramolecular Suzuki-Miyaura reaction has emerged as a powerful option for the construction of normal- and medium-sized rings as well as macrocycles, due to its stereospecificity, the mild reaction conditions, and the non-toxic nature of the boron by-products. In this review, we summarize the state-of-the-art of the application of intramolecular Suzuki-Miyaura cross-coupling reactions in the construction of (macro)cyclic frameworks of natural products and bioactive molecules of synthetic origin, covering (mostly) examples that have been reported since 2015. Target molecules prepared via intramolecular Suzuki-Miyaura cross-coupling as a key step range from natural products / natural product analogs to synthetic drug candidates, featuring ring sizes from 4 to >>12. We highlight the utility, scope, and limitations of the reaction for different ring sizes and arrays of functional groups. Where possible, comparisons with other methods of cyclization are provided.

A comprehensive review: medicinal applications and diverse synthetic strategies of pyrimidine-based compounds leveraging Suzuki and Sonogashira reactions

A comprehensive review: medicinal applications and diverse synthetic strategies of pyrimidine-based compounds leveraging Suzuki and Sonogashira reactions

Synthesis, Characterization, and Photochemistry of a Ga2L3 Coordination Cage with Dithienylethene-Catecholate Ligands.

Two new photoswitchable dithienylethene (DTE)-catechol ligands, specifically designed for group 13 metal coordination, were synthesized via Suzuki coupling reactions from a dichloro-DTE building block, each with varying longitudinal extensions. The shorter DTE-catechol ligand did not efficiently assemble with Ga3+ metal ions; however, elongation with a phenylene-amide spacer group enabled the successful formation of a novel triply DTE-functionalized coordination [Ga2L3]6- cage. This cage represents a unique example of integrating DTE photoswitches with main group metals in a supramolecular coordination framework. The [Ga2L3]6- cage was thoroughly characterized by NMR spectroscopy, including DOSY hydrodynamic volumetric analyses, high-resolution mass spectrometry, computational DFT, and photochemical analyses. The DFT studies highlighted the structural integrity and dynamic interplay within the helicate and mesocate isomeric forms of the [Ga2L3]6- cage upon photoswitching. While the free ligands exhibited all-photonic reversible switching at up to mM concentrations upon alternating irradiation at 365 and >495 nm, the [Ga2L3]6- cage demonstrated these capabilities under dilute μM conditions, albeit with lower efficiency and fatigue resistance. This behavior highlights the intricate relationship between rigid coordination with main group metals and the flexibility of the photoswitchable DTE ligands within the [Ga2L3]6- cage.

Palladium-Functionalized Polysiloxane Drop-Casted on Carbon Paper as a Heterogeneous Catalyst for the Suzuki-Miyaura Reaction.

In this work, a Pd(II)-C,N-cyclometalated complex was grafted to polysiloxanes via azide-alkyne cycloaddition. The obtained polymer-metal complex (Pd-PDMS) acts as a catalyst in the Suzuki-Miyaura reaction. Pd-PDMS was drop-casted onto a carbon fiber support, and the resulting membrane demonstrated catalytic activity in the cross-coupling reaction without yield loss after several catalytic cycles. The catalytic membrane allows for easy catalyst recycling and provides ultra-low palladium levels in Suzuki-Miyaura reaction products.

Novel Indolenine-Based hemicyanine dyes with extended π-Linker and auxiliary donor as potential Photosensitizers: Synthesis, Photophysical, electrochemical and computational Insights

Three novel hemicyanine dyes, D1-D3, were synthesized successfully based on dimethylaniline (DMA) and TPA donors and a carboxylated indolium vinyl acceptor linked through benzene unit as an extended π-spacer or through PTZ unit as an auxiliary donor to form the D1-π-A, D2-π-A & D2-D3-A systems, respectively. A multi-step process was conducted to yield the desired donor and acceptor intermediates. These were finally coupled through the Suzuki-Miyaura coupling and Knoevenagel condensation reactions to obtain the desired target dyes. A panchromatic response and a bathochromic shift of the ICT band maxima in the visible region were observed with the lowest band gap energy, Eg = 1.71 eV and λabs., max. = 590 nm, given by dye D3, were attributed to the presence of the auxiliary donor, PTZ. However, due to the high coplanarity of dye D1 it showed the highest absorptivity value of ε = 36462 M−1cm−1. The HOMO and LUMO levels are within the range suitable for smooth dye regeneration and electron ejection, EHOMO = -5.37 to −5.18 eV, and ELUMO = -3.47 to −3.27 eV. The density functional theory (DFT) and time-dependent TD-DFT at the B3LYP/6-31G(d,p) level were conducted to explore the bridged effect on geometric and TD-BHandH/6-31G(d,p) for optoelectronic properties.