Synthesis of Substituted 2,2’-Dinitrobiphenyls by a Novel Solvent-Free High Yielding Ullmann Coupling Biarylation:

Solvent-free reaction using a high-speed ball milling technique has been applied to the classical Ullmann coupling reaction for the first time. Biarylation of 2-iodonitrobenzene was achieved in quantitative yield when performed in a custom-made copper vial through continuous shaking without additional copper or solvent. The product was solid, NMR ready and required no lengthy extraction for purification. This reaction was cleaner, and faster than solution phase coupling which requires longer reaction time in high boiling solvents, added copper catalyst, and lengthy extraction and purification steps. Gram quantities of the biaryl compound were synthesized in larger copper vials. This is a general method that can be used to effectively reduce industrial waste en route to sustainability.

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Cross-Coupling Biarylation of Nitroaryl Chlorides Through High Speed Ball Milling

International Journal for Innovation Education and Research ◽

10.31686/ijier.vol3.iss6.376 ◽

2015 ◽

Vol 3 (6) ◽

pp. 12-35

Author(s):

Solita Lam ◽

Yvonne Puplampu Dove ◽

Adrienne Morris ◽

Ayunna Epps ◽

Ghislain R Mandouma

Keyword(s):

Ball Milling ◽

High Speed ◽

Coupling Reaction ◽

Cross Coupling ◽

Reaction Cross ◽

Extraction And Purification ◽

Custom Made ◽

Ball Milling Technique ◽

Solvent Free Reaction ◽

High Speed Ball Milling

Solvent-free reaction using a high-speed ball milling technique has been applied to the classical Ullmann coupling reaction. Cross-coupling biarylation of several nitroaryl chlorides was achieved in good yields when performed in custom-made copper vials through continuous shaking without additional copper or solvent. Cross-coupling products were obtained almost pure and NMR-ready. These reactions were cleaner than solution phase coupling which require longer reaction time in high boiling solvents, and added catalysts as well as lengthy extraction and purification steps. Gram quantities of cross biaryl compounds have been synthesized with larger copper vials, a proof that this method can be used to reduce industrial waste and for sustainability.

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Solvent-free Sonogashira coupling reaction via high speed ball milling

Green Chemistry ◽

10.1039/b915669k ◽

2009 ◽

Vol 11 (11) ◽

pp. 1821 ◽

Cited By ~ 144

Author(s):

Dennis A. Fulmer ◽

William C. Shearouse ◽

Shareika T. Medonza ◽

James Mack

Keyword(s):

Ball Milling ◽

High Speed ◽

Coupling Reaction ◽

Solvent Free ◽

Sonogashira Coupling ◽

Sonogashira Coupling Reaction ◽

High Speed Ball Milling

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ChemInform Abstract: Solvent-Free Sonogashira Coupling Reaction via High Speed Ball Milling.

ChemInform ◽

10.1002/chin.201012061 ◽

2010 ◽

Vol 41 (12) ◽

Author(s):

Dennis A. Fulmer ◽

William C. Shearouse ◽

Shareika T. Medonza ◽

James Mack

Keyword(s):

Ball Milling ◽

High Speed ◽

Coupling Reaction ◽

Solvent Free ◽

Sonogashira Coupling ◽

Sonogashira Coupling Reaction ◽

High Speed Ball Milling

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Isolation and HPLC Determination of the Chemical Components of Gentianella acuta (Michx.) Hulten

Current Analytical Chemistry ◽

10.2174/1573411014666180730113804 ◽

2018 ◽

Vol 15 (1) ◽

pp. 21-33

Author(s):

Ying Wei ◽

Yongqiao Liu ◽

Yifan Hele ◽

Weiwei Sun ◽

Yang Wang ◽

...

Keyword(s):

Medicinal Plant ◽

High Speed ◽

Chemical Constituents ◽

Folk Medicine ◽

Gradient Elution ◽

Chemical Components ◽

Isolation And Characterization ◽

Major Chemical ◽

Main Components ◽

First Time

Background: Gentianella acuta (Michx.) Hulten is an important type of medicinal plant found in several Chinese provinces. It has been widely used in folk medicine to treat various illnesses. However, there is not enough detailed information about the chemical constituents of this plant or methods for their content determination. Objective: The focus of this work is the isolation and characterization of the major chemical constituents of Gentianella acuta, and developing an analytical method for their determination. Methods: The components of Gentianella acuta were isolated using (1) ethanol extraction and adsorption on macroporous resin. (2) and ethyl acetate extraction and high speed countercurrent chromatography. A HPLC-DAD method was developed using a C18 column and water-acetonitrile as the mobile phase. Based on compound polarities, both isocratic and gradient elution methods were developed. Results: A total of 29 compounds were isolated from this plant, of which 17 compounds were isolated from this genus for the first time. The main components in this plant were found to be xanthones. The HPLC-DAD method was developed and validated for their determination, and found to show good sensitivity and reliability. Conclusion: The results of this work add to the limited body of work available on this important medicinal plant. The findings will be useful for further investigation and development of Gentianella acuta for its valuable medicinal properties.

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Microfluidic resonators with two parallel channels for independent sample loading and effective density tuning

Micro and Nano Systems Letters ◽

10.1186/s40486-020-00119-8 ◽

2020 ◽

Vol 8 (1) ◽

Cited By ~ 1

Author(s):

Jungchul Lee ◽

Faheem Khan ◽

Thomas Thundat ◽

Bong Jae Lee

Keyword(s):

Silicon Nitride ◽

Potassium Hydroxide ◽

Laser Doppler Vibrometer ◽

Effective Density ◽

Fluidic Channel ◽

Custom Made ◽

Sample Density ◽

Polysilicon Layer ◽

Parallel Channels ◽

First Time

ABSTRACTThis paper reports doubly clamped microchannel embedded resonators with two independent and parallel channels integrated for effective sample density tuning for the first time. With the aid of such a unique design, each fluidic channel can be independently accessed thus different liquid samples can be loaded simultaneously. The proposed fluidic resonators are batch fabricated by depositing silicon nitride, polysilicon, and silicon nitride sequentially on top of a set of 4-inch silicon wafers and sacrificing the middle polysilicon layer with potassium hydroxide (KOH). The sacrificial process defines two parallel channels and releases doubly clamped beam resonators simultaneously. In addition, an off-chip vacuum clamp with optical and fluidic access is custom-made to operate each resonator with enhanced quality factor. The microfluidic resonators mounted on the custom vacuum clamp are thoroughly characterized with a laser Doppler vibrometer and used to measure the effective sample density ranging from 395 to 998 kg/m3.

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Getting High: High Fidelity Simulation of High Granularity Calorimeters with High Speed

Computing and Software for Big Science ◽

10.1007/s41781-021-00056-0 ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

Erik Buhmann ◽

Sascha Diefenbacher ◽

Engin Eren ◽

Frank Gaede ◽

Gregor Kasieczka ◽

...

Keyword(s):

Particle Physics ◽

High Speed ◽

Deep Neural Networks ◽

High Fidelity ◽

High Fidelity Simulation ◽

Physical Processes ◽

Electromagnetic Showers ◽

Information Bottleneck ◽

First Time ◽

Processing Network

AbstractAccurate simulation of physical processes is crucial for the success of modern particle physics. However, simulating the development and interaction of particle showers with calorimeter detectors is a time consuming process and drives the computing needs of large experiments at the LHC and future colliders. Recently, generative machine learning models based on deep neural networks have shown promise in speeding up this task by several orders of magnitude. We investigate the use of a new architecture—the Bounded Information Bottleneck Autoencoder—for modelling electromagnetic showers in the central region of the Silicon-Tungsten calorimeter of the proposed International Large Detector. Combined with a novel second post-processing network, this approach achieves an accurate simulation of differential distributions including for the first time the shape of the minimum-ionizing-particle peak compared to a full Geant4 simulation for a high-granularity calorimeter with 27k simulated channels. The results are validated by comparing to established architectures. Our results further strengthen the case of using generative networks for fast simulation and demonstrate that physically relevant differential distributions can be described with high accuracy.

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Solvent-Free Processing of Drug-Loaded Poly(ε-Caprolactone) Scaffolds with Tunable Macroporosity by Combination of Supercritical Foaming and Thermal Porogen Leaching

Polymers ◽

10.3390/polym13010159 ◽

2021 ◽

Vol 13 (1) ◽

pp. 159

Author(s):

Víctor Santos-Rosales ◽

Inés Ardao ◽

Leticia Goimil ◽

Jose Luis Gomez-Amoza ◽

Carlos A. García-González

Keyword(s):

Bone Repair ◽

Drug Loading ◽

Ammonium Bicarbonate ◽

Bone Diseases ◽

Solvent Free ◽

Bone Integration ◽

Bioactive Agents ◽

First Time ◽

Supercritical Foaming ◽

Foaming Technology

Demand of scaffolds for hard tissue repair increases due to a higher incidence of fractures related to accidents and bone-diseases that are linked to the ageing of the population. Namely, scaffolds loaded with bioactive agents can facilitate the bone repair by favoring the bone integration and avoiding post-grafting complications. Supercritical (sc-)foaming technology emerges as a unique solvent-free approach for the processing of drug-loadenu7d scaffolds at high incorporation yields. In this work, medicated poly(ε-caprolactone) (PCL) scaffolds were prepared by sc-foaming coupled with a leaching process to overcome problems of pore size tuning of the sc-foaming technique. The removal of the solid porogen (BA, ammonium bicarbonate) was carried out by a thermal leaching taking place at 37 °C and in the absence of solvents for the first time. Macroporous scaffolds with dual porosity (50–100 µm and 200–400 µm ranges) were obtained and with a porous structure directly dependent on the porogen content used. The processing of ketoprofen-loaded scaffolds using BA porogen resulted in drug loading yields close to 100% and influenced its release profile from the PCL matrix to a relevant clinical scenario. A novel solvent-free strategy has been set to integrate the incorporation of solid porogens in the sc-foaming of medicated scaffolds.

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Umpolung Coupling of Pyridine-2-carboxaldehydes and Propargylic Carbonates via N-Heterocyclic Carbene/Palladium Synergetic Catalysis

Chemical Communications ◽

10.1039/d1cc01311d ◽

2021 ◽

Author(s):

Weiyang Bi ◽

Yunhui Yang ◽

Song Ye ◽

Congyang Wang

Keyword(s):

Palladium Catalyst ◽

Coupling Reaction ◽

Cross Coupling ◽

Cooperative Catalysis ◽

Cross Coupling Reaction ◽

First Time

The umpolung cross-coupling reaction of pyridine-2-carboxaldehydes and propargylic carbonates has been developed for the first time through N-heterocyclic carbene/palladium cooperative catalysis with the judicious selections of the palladium catalyst, ligand...

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Extra-gastric expression of the proton pump H+/K+-ATPase in the gills and kidney of the teleost Oreochromis niloticus

Journal of Experimental Biology ◽

10.1242/jeb.214890 ◽

2020 ◽

Vol 223 (16) ◽

pp. jeb214890

Author(s):

Ebtesam Ali Barnawi ◽

Justine E. Doherty ◽

Patrícia Gomes Ferreira ◽

Jonathan M. Wilson

Keyword(s):

Oreochromis Niloticus ◽

Cellular Localization ◽

Ex Vivo ◽

Uptake Inhibition ◽

Custom Made ◽

Potassium Regulation ◽

Immunohistochemical Techniques ◽

Collecting Tubules ◽

First Time

ABSTRACTPotassium regulation is essential for the proper functioning of excitable tissues in vertebrates. The H+/K+-ATPase (HKA), which is composed of the HKα1 (gene: atp4a) and HKβ (gene: atp4b) subunits, has an established role in potassium and acid–base regulation in mammals and is well known for its role in gastric acidification. However, the role of HKA in extra-gastric organs such as the gill and kidney is less clear, especially in fishes. In the present study in Nile tilapia, Oreochromis niloticus, uptake of the K+ surrogate flux marker rubidium (Rb+) was demonstrated in vivo; however, this uptake was not inhibited with omeprazole, a potent inhibitor of the gastric HKA. This contrasts with gill and kidney ex vivo preparations, where tissue Rb+ uptake was significantly inhibited by omeprazole and SCH28080, another gastric HKA inhibitor. The cellular localization of this pump in both the gill and kidney was demonstrated using immunohistochemical techniques with custom-made antibodies specific for Atp4a and Atp4b. Antibodies against the two subunits showed the same apical ionocyte distribution pattern in the gill and collecting tubules/ducts in the kidney. Atp4a antibody specificity was confirmed by western blotting. RT-PCT was used to confirm the expression of both subunits in the gill and kidney. Taken together, these results indicate for the first time K+ (Rb+) uptake in O. niloticus and that HKA is implicated, as shown through the ex vivo uptake inhibition by omeprazole and SCH28080, verifying a role for HKA in K+ absorption in the gill's ionocytes and collecting tubule/duct segments of the kidney.

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