Gold-catalyzed addition reaction between creatinine and isatin:A sustainable and green chemistry approach for the diastereoselective synthesis of 3-substituted-3-hydroxyisatins

The aldolization of various isatins with creatinine under gold catalysis in water has been developed.The reaction is operationally simple as the products can be isolated by simple filtration without requiring tedious solvent extraction and column chromatographic techniques.The generality of this methodology is showcased through the reactions of a wide range of isatin derivatives with creatinine to afford the respective aldol products in excellent yields with complete syn‐selectivity.The scope of this chemistry is further extended to a tandem reaction involving isatins,creatinine and malononitrile to afford multicomponent products in excellent yields with complete anti‐selectivity.The antioxidant potency of the synthesized compound was assessed by a spectrophotometric method,which revealed that three compounds containing halogen atoms(2c,2d and2e)were the most active compared with the standard.

Microwave Assisted One-Pot Preparation of Quinoline Derivatives without any Solvent According to Green Chemistry

The convenient and efficient procedure for one-pot preparation of quinaldine derivatives from multi component reaction of anilines, acetone and benzaldehyde without any solvent under microwave irradiation on the surface of alumina impregnated with hydrochloric acid is developed.

Green Chemistry Allometry Test of Microwave-Assisted Synthesis of Transition Metal Nanostructures

Microwave irradiation is considered an important approach to Green Chemistry, because of its ability to rapidly increase the internal temperature of polar-organic compounds that lead to synthesis times of minutes rather than hours when compared to conventional thermal heating. This works describes a dual allometry test for the discrimination between the solvents and reagents used in the microwave-assisted synthesis of transition metal (zinc oxide, palladium silver, platinum, and gold) nanostructures. The test is performed in log-log process energy phase-space projection, where the synthesis data (kJ against kJ·mol-1) has a power-law signature. The test is shown to discriminate between recommended Green Chemistry, problematic Green Chemistry, and Green Chemistry hazardous solvents. Typically, recommended Green chemistry exhibits a broad y-axes distribution within an upper exponent = 1 and lower exponent = 0.5. Problematic Green Chemistry exhibits a y-axes narrower distribution with an upper exponent = 0.94 and lower exponent = 0.64. Non-Green Chemistry hazardous data exhibits a further narrowing of the y-axes distribution within upper exponent = 0.87 and lower exponent = 0.66. In all three cases, the y-axes is aligned to original database power-law signature. It is also shown that in the x-axes direction (process energy budget) the grouped order of magnitude decreases from four orders for recommended Green Chemistry solvent and reagent data, through two orders for non-Green Chemistry hazardous material and down to one order for problematic Green Chemistry.

The Technology of Green Chemistry and Its Function in Redox Response and: Environmentally Friendly Technology for Sustainable Development: Assessment of Recent Findings

Sustainability is the ability to nurture or support a process for a long time without compromising the needs of future generations. Rather, sustainable chemistry is a term that refers to the production of chemical products and processes that reduce or eliminate the use and production of hazardous substances. Green chemistry creates alternative technologies that are safer for human health and the environment to prevent further damage to human health and the environment, such as reducing the release of hazardous chemicals into the air, leading to reduced lung damage. Although sustainable and environmentally friendly technologies have evolved in other areas of science, their use in redox reactions and industry is still in its early stages. The current review aims to highlight the need for green chemistry as a sustainable chemistry and its principles and its application to produce environmentally friendly industrial products and to reduce or stop the production of harmful intermediates and products during its synthesis process.

Developing From Tranditional Microscale Chemistry to Microscale Green Chemistry

Microscale chemistry is appealing to all levels of education.In contrast to conventional macroscale chemistry,only minute amount of chemicals are required to undertaking a chemical investigation.……

Green analytical chemistry metrics for evaluating the greenness of analytical procedures

Green analytical chemistry(GAC)focuses on mitigating the adverse effects of analytical activities on human safety,human health,and environment.In addition to the 12 principles of GAC,proper GAC tools should be developed and employed to assess the greenness of different analytical assays.The 15 widely used GAC metrics,i.e.,national environmental methods index(NEMI),advanced NEMI,assessment of green profile(AGP),chloroform-oriented toxicity estimation scale(ChlorTox Scale),Analytical Eco-Scale,Green Certificate Modified Eco-Scale,analytical method greenness score(AMGS),green analytical procedure index(GAPI),ComplexGAPI,red-green-blue(RGB)additive color model,RGB 12 algorithm,analytical greenness calculator(AGREE),AGREE preparation(AGREEprep),HEXAGON,and blue applicability grade index(BAGI),are selected as the typical tools.This article comprehensively presents and elucidates the principles,characteristics,merits,and demerits of 15 widely used GAC tools.This review is helpful for researchers to use the current GAC metrics to assess the environmental sustainability of analytical assays.

Promotion of GSC Technology Innovation by the Green and Sustainable Chemistry Network

The Green and Sustainable Chemistry Network （GSCN） has been promoting GSC technology development since 2000 in three major activities, holding the GSC symposium, running the GSC Awards, and providing the information related to GSC in Japan. GSCN holds a vision to expand the philosophy of GSC not only to the domestic, but also to the global. As for a regional network in Asia and Oceania, we established the Asia-Oceania GSC Network, and we hope to expand the Network to all countries.

A green chemistry approach for the synthesis and characterization of bioactive gold nanoparticles using Azolla microphylla methanol extract

This article reports the environmentally benign synthesis of gold nanoparticles （GNPs） using methanol extract of Azolla microphylla as the stabilizing and reducing agent. The GNPs were characterized by UV-vis spectrophotometry and FTIR, and the morphological characteristics were analyzed by XRD, FESEM-EDX and HRTEM. The GNPs could be formed in very short time, even in less than 30 min. The nanoparticles measured by UV-spectrophotometer demonstrated a peak at 540 nm corresponding to surface plasmon resonance spectra, and the peaks showed by FTIR suggested the presence of organic biomolecules on the surface of the GNPs. XRD results confirmed the crystalline nature of the GNPs, and FESEM-EDX and HRTEM analyses had been performed in the size ranges of 17-40nm and 1.25-17.5nm respectively. The synthesized GNPs showed excellent antioxidant activity. This study shows the feasibility of using plant sources for the biosynthesis of GNPs.

Green chemistry of chromate cleaner production

Research topics and methods of green chemistry in chromate production are introduced in this paper. New original green chemical process of the heterogeneous reaction and separation system of liquid phase oxidation of chromite in molten salt of sodium hydroxide—one way separation in high concentration medium—metastable phase separation—carbonate recycle conversion has been developed. The green commercial process for comprehensive utilization of mineral resources—reactant recycle inside the process—zero emission was established.

A green cross-linking method for the preparation of renewable threedimensional graphene sponges for efficient adsorption of Congo red dye

Graphene-based materials possess significant potential for the treatment of dye wastewater due to their exceptional adsorption properties toward stubborn pollutants.However,their utilization is hindered by high preparation costs,low yields,environmental pollution during synthesis,and challenges in regenerating the adsorbent.This study proposes a novel approach to address these limitations by developing nitrogen-doped three-dimensional(3D)polyvinyl alcohol(PVA)crosslinked graphene sponges(N-PGA)using a cross-linking method with ammonium carbonate.This method offers a relatively mild,environmentally friendly approach.Ammonium carbonate serves as both a reducing and modifying agent,facilitating the formation of the intrinsic structure of N-PGA and acting as a nitrogen source.Meanwhile,PVA is utilized as the cross-linking agent.The results demonstrate that N-PGA exhibits a favorable internal 3D hierarchical porous structure and possesses robust mechanical properties.The measured specific surface area(BET)of N-PGA was as high as406.538 m^(2)·g^(-1),which was favorable for its efficient adsorption of Congo red(CR)dye molecules.At an initial concentration of 50 mg·L^(-1),N-PGA achieved an impressive removal rate of 89.6%and an adsorption capacity of 112 mg·g^(-1)for CR dye.Furthermore,it retained 79%of its initial adsorption capacity after 10 cycles,demonstrating excellent regeneration performance.In summary,the synthesized N-PGA displays remarkable efficacy in the adsorption of CR dye in wastewater,opening up new possibilities for utilizing 3D porous graphene nanomaterials as efficient adsorbents in wastewater treatment.

Supercritical fluids:Clean solvents for green chemistry

Supercritical fluids are becoming increasingly attractive as environmentally acceptable replacement for organic solvents in chemical reactions and material processing. This paper highlights some of the properties of supercritical fluids, especially supercritical CO2, which offer particular advantages for the handling of polymers, metal complexes and the environmentally more friendly synthesis and manufacture of chemicals. The paper includes same of the researches in University of Nottingham and a number of recent reviews which together provide a comprehensive introduction.

IR-EcoSpectra: Exploring sustainable ex situ and in situ FTIR applications for green chemical and pharmaceutical analysis

In various industries,particularly in the chemical and pharmaceutical fields,Fourier transform infrared spectroscopy(FTIR)spectroscopy provides a unique capacity to detect and characterise complex chemicals while minimising environmental damage by minimal waste generation and reducing the need for extensive sample preparation or use of harmful reagents.This review showcases the versatility of ex situ and in situ FTIR applications for substance identification,analysis,and dynamic monitoring.Ex situ FTIR spectroscopy’s accuracy in identifying impurities,monitoring crystallisation processes,and regulating medication release patterns improves product quality,safety,and efficacy.Furthermore,its quantification capabilities enable more effective drug development,dosage procedures,and quality control practices,all of which are consistent with green analytical principles.On the other hand,in situ FTIR spectroscopy appears to be a novel tool for the real-time investigation of molecular changes during reactions and processes,allowing for the monitoring of drug release kinetics,crystallisation dynamics,and surface contacts,as well as providing vital insights into material behaviour.The combination of ex situ FTIR precision and in situ FTIR dynamic capabilities gives a comprehensive analytical framework for developing green practices,quality control,and innovation in the chemical and pharmaceutical industries.This review presents the wide range of applications of ex situ and in situ FTIR spectroscopy in chemical,pharmaceutical and medical fields as an analytical green chemistry tool.However,further study is required to fully realise FTIR’s potential and develop new applications that improve sustainability in these areas.

Plasma methods for preparing green catalysts: Current status and perspective

Most current catalyst preparation methods cause pollution to air, water and land with the use of hazardous chemicals, lengthy operation time, high energy input and excessive water usage. The development of green catalyst preparation is necessary to prevent and eliminate waste from each step of the catalyst preparation. We summarize recent progress in the application of cold plasmas for green catalyst preparation. Cold plasma preparation can reduce the catalyst size, improve the dispersion and enhance catalyst-support interaction with the use of less or no hazardous chemicals. These improvements also lead to the enhancement of catalyst activity and stability. An alternative room temperature electron reduction with a non-hydrogen plasma as an electron source was developed for the reduction of noble metal ions in which no hazardous chemical reducing agent or hydrogen was needed. This creates many opportunities for the development of supported catalysts with heat sensitive substrates, including metal organic frameworks （MOFs）, covalent organic framework（COFs）, high surface area carbon, peptide, DNA, proteins and others. A novel floating metal catalyst on a water（or solution） surface has been established. Template removal using low temperature cold plasmas also leads to the formation of high surface area porous materials with characteristics that are normally only obtainable with high temperature calcination, but sintering can be avoided. Micro combustion has been developed for the removal of carbon template using cold plasma. This is promising for preparing many structured oxides in a simple way with no use of auxiliary chemicals. Many opportunities exist for the use of cold plasmas to make multi-metallic oxides. Some future development ideas are addressed.

Green Production Technology of the Monomer of Nylon-6： Caprolactam

After two decades＇ endeavor, the Research Institute of Petroleum Processing （RIPP） has successfully de- veloped a green caprolactam （CPL） production technology. This technology is based on the integration of titanium silicate （TS）-I zeolite with the slurry-bed reactor for the ammoximation of cyclohexanone, the integration of silicalite-1 zeolite with the moving-bed reactor for the gas-phase rearrangement of cyclohex- anone oxime, and the integration of an amorphous nickel （Ni） catalyst with the magnetically stabilized bed reactor for the purification of caprolactam. The world＇s first industrial plant based on this green CPL produc- tion technology has been built and possesses a capacity of 200 kt·a-1. Compared with existing technologies, the plant investment is pronouncedly reduced, and the nitrogen （N） atom utilization is drastically improved. The waste emission is reduced significantly; for example, no ammonium sulfate byproduct is produced. As a result, the price difference between CPL and benzene drops. In 2015, the capacity of the green CPL produc- tion technology reached 3 ×10-6 t·a-1, making China the world＇s largest CPL producer, with a global market share exceeding 50%.

An Efficient and Green Procedure for the Preparation of gem-Dicar- boxylates from Aldehydes Catalyzed by Fe_2(SO_4)_3·xH_2O

An efficient and environmentally benign conversion of aldehydes into the corresponding gem-dicarboxylates was realized by using hydrated ferric sulfate as a heterogeneous catalyst. In addition to its high efficiency, the catalyst can be recovered simply and reused efficiently for at least seven times.

One-Step Preparation of Green Fabric for Continuous Antibacterial Applications

Polypropylene(PP)scaffolds are the most commonly used biomedical scaffolds despite their disadvan-tages,which include problems with adhesion,infection,and inflammatory responses.Here,we report on the successful development of a facile one-step method to fabricate a series of novel triclosan poly-dopamine polypropylene(TPP)composite scaffolds and thereby effectively improve the biocompatibility and long-term antibacterial properties of PP scaffolds.The antibacterial triclosan can effectively interact with dopamine during biocompatible polydopamine formation on the PP scaffold by one-step green fab-rication.Thanks to the sustained release of triclosan from the biocompatible polydopamine coating,a 5mm×5mm sample of TPP-coated scaffold made with a triclosan concentration of 8 mg-mL^(-1)(referredto herein as TPP-8)exhibited a continuous antibacterial effect against both Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)for more than 15d,at maximum antibacterial volumes of 2 and 5mL,respectively.Our study establishes a new direction for facile long-term antibacterial studies for medical applications.

Nanoscale graphene oxide sheets as highly efficient carbocatalysts in green oxidation of benzylic alcohols and aromatic aldehydes

Nanoscale graphene oxide(NGO)sheets were synthesized and used as carbocatalysts for effectiveoxidation of benzylic alcohols and aromatic aldehydes.For oxidation of alcohols in the presence ofH2O2at80°C,the NGOs(20%mass fraction)as carbocatalysts showed selectivity toward aldehyde.The rate and yield of this reaction strongly depended on the nature of substituents on the alcohol.For4‐nitrobenzyl alcohol,<10%of it was converted into the corresponding carboxylic acid after24h.By contrast,4‐methoxybenzyl alcohol and diphenylmethanol were completely converted into thecorresponding carboxylic acid and ketone after only9and3h,respectively.The conversion ratesfor oxidation of aromatic aldehydes by NGO carbocatalysts were higher than those for alcohol oxidation.For all the aldehydes,complete conversion to the corresponding carboxylic acids wasachieved using7%(mass fraction)of NGO at70°C within2–3h.Possible mechanisms for NGOcarbocatalyst structure‐dependent oxidation of benzyl alcohols and structure‐independent oxidationof aromatic aldehydes are discussed.

Opportunities and Challenges for the Development of Green Detergents

The characteristic of green detergents and it＇s difference with regular detergent was expounded in this paper, according to the kernel of green chemistry. The variation trends of Chinese mainstream consumer group show that the new mainstream consumer group are concerning more and more about household detergent, especially its safety to human and environment. Growing attention of the mainstream consumer group and the standard drafting units on detergent will promote the development of green detergents, however, there are still challenges for the development of green detergents.

Systematic Selection of Green Solvents for Organic Reacting Systems

The solvent selection methodology developed earlier by. Gani （tal. （Comp. Chem. Eng., 2005）has been extended to handle multi-step reaction systems. The solvent selection problem was formulated based on the methodology guidelines, and solved using ICAS software tool. A list with solvent candidates is generated so that it can be further investigated experimentally. Comments and clarifications from chemists have been incorporated into the problem forrnulations to clarify the role of the solvents in the chemistry and potential reactivity issues. Highly promising results were obtained, in accordance with. industrial process data.

Evaluation of natamycin in commercial dairy products by a green capillary zone electrophoresis method and confirmation with a Liquid Chromatography-Mass Spectrometry

In the present study,a simple,rapid,sensitive,robust,convenient,economical and environmentally friendly Capillary Zone Electrophoresis(CZE)method based on the use of non-toxic chemicals was developed to monitor the concentrations of natamycin,which is used to prevent mold and yeast that may occur in cheese crust,cheese crumb,yogurt and ayran.Additionally,a LC-ESI-MS method was developed and used for confirmation as well.The validated methods produced excellent results in terms of linearity(R2>0.999)and recovery values(ranging from 99.06%to 100.54%)and successfully applied for the analysis of natamycin,according to European regulations and Turkish Food Codex in 14 different brands of ayran,17 different brands of yogurt and 12 different brands of Kashar cheese collected from local markets.CZE demonstrated flexibility,sensitivity and selectivity,accuracy,robustness,and low cost.The developed CZE method is very advantageous because it is environmentally friendly and economical due to the analysis time and the absence of organic solvents.In addition,the reliability of the study was increased by using the internal standard and possible errors were prevented.Both CZE and LC-MS methods provided good results for natamycin analysis and these methods can be used for natamycin analysis in dairy products and possible pharmaceuticals.Finally,embracing the primary concepts of green chemistry,the proposed technique can be taken into consideration friendly to the nature,sustainable and“reagent-free”.These assays are easily applicable as quality control methods for natural products and pharmaceuticals containing natamycin.