scispace - formally typeset
Journal ArticleDOI: 10.1080/10426507.2020.1835905

WEB (water extract of banana): An efficient natural base for one-pot multi-component synthesis of 2-amino-3,5-dicarbonitrile-6-thio-pyridines

04 Mar 2021-Phosphorus Sulfur and Silicon and The Related Elements (Informa UK Limited)-Vol. 196, Iss: 3, pp 328-336
Abstract: One-pot multi-component synthesis of 2-amino-3,5-dicarbonitrile-6-thio-pyridines derivatives using WEB (water extract of banana peels ash) as a green catalyst is described. A variety of aromatic al...

... read more


7 results found

Open accessDOI: 10.1039/X0XX00000X
01 Jan 2016-
Abstract: Advanced materials are essential to the quality of modern day life, but the synthesis of these compounds is often inefficient in terms of energy, time and resources; especially when considering the hydrothermal batch methods used to prepare many such compounds – often requiring week-long reaction times with variable yields and product quality. In contrast, Continuous flow synthesis (CFS) provides a more readily scalable means for the efficient, effective and reproducible synthesis of inorganic compounds. This publication demonstrates the novel CFS of several metal ammonium phosphates and compare the effect of synthesis route on particle size, size distribution, and crystallinity.

... read more

265 Citations

Journal ArticleDOI: 10.1007/S10311-021-01253-4
Katta Venkateswarlu1Institutions (1)
Abstract: The decline of fossil- and ore-based materials is calling for more recycling of waste into new materials Here, I review the recycling of ashes from biomass into reagents for chemical synthesis and biodiesel production Biomass includes banana, pomegranate, rice, papaya, century plant, water hyacinth, bael fruit, nilgiri, mango, onion, muskmelon fruit, pomelo, lemon fruit, teak and tamarind Chemical reactions include Knoevenagel condensation, Suzuki–Miyaura cross-coupling, Sonogashira reaction, Dakin reaction, Henry reaction, Ullmann coupling, Pd-catalyzed homocoupling, aromatic bromination, hydroxylation of arylboronic acids, hydration of nitriles and azide–alkyne click reaction The synthesis of peptide bonds, disulfides, aminochromenes, carboxycoumarins, diazohydroxy esters, imidazopyridines, pyranopyrazoles, chalcones, flavones and bisenols is described

... read more

Topics: Knoevenagel condensation (51%)

6 Citations

Journal ArticleDOI: 10.1007/S41061-021-00346-6
U. P. Patil1, Suresh S. Patil1Institutions (1)
Abstract: Catalysts are the jewel in the crown of the chemical industry, accelerating reaction kinetics and augmenting the efficiency of desired reaction paths. Natural feedstock is a renewable resource capable of providing valuable functional products; in addition, it confers an opportunity to create catalysts. As an alternative to stoichiometric reagents, and as a part of a sustainable approach, the implications of using natural feedstocks as a source of new catalysts has attracted considerable interest. Natural feedstock-derived catalysts can promote chemical transformations more efficiently. Recent reports have highlighted the significant role of these biogenic, cost-effective, innocuous, biodegradable materials as catalysts in many biologically and pharmacologically important protocols. This review outlines the decisive organic transformations for which feedstock-derived catalysts have been employed effectively and successfully, along with their economic and environmental benefits over traditional catalytic systems.

... read more

1 Citations

Journal ArticleDOI: 10.1016/J.SCP.2021.100551
Abstract: The minimization of generation of wastes or their eradication is a crucial aspect of Green Chemistry. As such, the design of processes that involve any or both the two, is of utmost concern. In addition, the elimination of hazardous materials and the utilization of safer alternatives are important. The use of agricultural waste biomass ash, in the form of their aqueous extracts, excludes the need of harmful volatile organic compounds (VOCs) in a number of organic transformations, thereby enhancing the greener aspect. Herein, we highlight the utility of aqueous extracts of agricultural waste in some significant organic transformations. Majority of them are sourced from the peels of fruits and seeds which normally fall under the category of “Household Waste”.

... read more

Topics: Hazardous waste (56%)

Journal ArticleDOI: 10.1007/S10311-021-01343-3
Abstract: Agro-waste extracts are considered green solvents since they are easy to handle, readily accessible from natural waste feedstock, biodegradable and recyclable. Therefore, the employment of these extracts in reaction media has emerged as the most useful and eco-friendly alternative in modern organic chemistry. Here, we review recent developments for the generation of new carbon–carbon and carbon–heteroatom bonds mediated by agro-waste extracts. We show that these aqueous extracts have great applicability in several transformations, including condensations, oxidations, multicomponent and coupling reactions. The challenges and advantages on the use of water of agro-waste extracts in synthetic methodologies is also detail.

... read more


82 results found

Journal ArticleDOI: 10.1002/ANIE.200460548
Diego J. Ramón1, Miguel Yus1Institutions (1)
04 Mar 2005-Angewandte Chemie
Abstract: Asymmetric multicomponent reactions involve the preparation of chiral compounds by the reaction of three or more reagents added simultaneously. This kind of addition and reaction has some advantages over classic divergent reaction strategies, such as lower costs, time, and energy, as well as environmentally friendlier aspects. All these advantages, together with the high level of stereoselectivity attained in some of these reactions, will force chemists in industry as in academia to adopt this new strategy of synthesis, or at least to consider it as a viable option. The positive aspects as well as the drawbacks of this strategy are discussed in this Review.

... read more

1,410 Citations

Journal ArticleDOI: 10.1039/B418069K
Roger A. Sheldon1Institutions (1)
03 May 2005-Green Chemistry
Abstract: The growing awareness of the pressing need for greener, more sustainable technologies has focused attention on the use of atom efficient catalytic methodologies for the manufacture of fine chemicals and pharmaceuticals. Another aspect which is receiving increasing attention is the use of alternative reaction media that circumvent the problems associated with many of the traditional volatile organic solvents. The use of nonconventional reaction media also provides opportunities for facilitating the recovery and recycling of the catalyst. The state of the art in the use of alternative reaction media for green, sustainable organic synthesis is reviewed. Liquid–liquid biphasic catalysis provides an industrially attractive method for the recovery and recycling of catalysts as an alternative to the more traditional solid heterogeneous catalysts. Various approaches to liquid–liquid biphasic catalysis—aqueous biphasic, fluorous biphasic, supercritical carbon dioxide, ionic liquids and various combinations thereof—are reviewed and compared. “The best solvent is no solvent” but if a solvent is needed then water has a lot to recommend it and catalysis in aqueous biphasic systems is an industrially attractive methodology which has found broad application. Similarly, supercritical carbon dioxide is an interesting reaction medium in the context of green chemistry and catalysis in various mono- and biphasic systems involving this solvent are reviewed. Fluorous biphasic systems and ionic liquids also have advantages in certain situations and the advantages and limitations of these media are compared. The ultimate in clean catalytic technologies is to telescope multistep syntheses into one-pot in the form of catalytic cascade processes. Examples of such catalytic cascades involving both chemo- and biocatalytic conversions are presented. Biocatalysis has a distinct advantage in this context in that the reactions all take place at or close to ambient temperature and pressure. In emulation of natural processes, where several different enzymes are compartmentalised in the cell, it can be advantageous to immobilise the various catalysts in such a cascade process. In this context, a novel and effective method for the immobilisation of enzymes as cross-linked enzyme aggregates (CLEAs) is discussed and the use of a combi CLEA, containing two enzymes, for the one-pot conversion of benzaldehyde to S-mandelic acid is reported.

... read more

Topics: Catalysis (50%)

1,254 Citations

Journal ArticleDOI: 10.1039/C3GC41935E
Roger A. Sheldon1Institutions (1)
25 Feb 2014-Green Chemistry
Abstract: The various strategies for the valorisation of waste biomass to platform chemicals, and the underlying developments in chemical and biological catalysis which make this possible, are critically reviewed. The option involving the least changes to the status quo is the drop-in strategy of complete deoxygenation to petroleum hydrocarbons and further processing using existing technologies. The alternative, redox economic approach, is direct conversion of, for example, carbohydrates to oxygenates by fermentation or chemocatalytic processes. Examples of both approaches are described, e.g. fermentation of carbohydrates to produce hydrocarbons, lower alcohols, diols and carboxylic acids or acid catalyzed hydrolysis of hexoses to hydroxymethyl furfural (HMF) and subsequent conversion to levulinic acid (LA), γ-valerolactone (GVL) and furan dicarboxylic acid (FDCA). Three possible routes for producing a bio-based equivalent of the large volume polymer, polyethylene terephthalate (PET) are delineated. Valorisation of waste protein could, in the future, form an important source of amino acids, such as L-glutamic acid and L-lysine, as platform chemicals, which in turn can be converted to nitrogen containing commodity chemicals. Glycerol, the coproduct of biodiesel manufacture from triglycerides, is another waste stream for which valorisation to commodity chemicals, such as epichlorohydrin and acrolein, is an attractive option.

... read more

Topics: Commodity chemicals (61%), Levulinic acid (52%), Valorisation (51%) ... show more

1,029 Citations

Journal ArticleDOI: 10.2174/0929867033368600
Christopher Hulme1, Vijay Keshav Gore1Institutions (1)
Abstract: With the recent emergence of combinatorial chemistry and high-speed parallel synthesis for drug discovery applications, the multi-component reaction (MCR) has seen a resurgence of interest. Easily automated one-pot reactions, such as the Ugi and Passerini reactions, are powerful tools for producing diverse arrays of compounds, often in one step and high yield. Despite this synthetic potential, the Ugi reaction is limited by producing products that are flexible and peptide-like, often being classified as 'non drug-like'. This review details developments of new, highly atom-economic MCR derived chemical methods, which enable the fast and efficient production of chemical libraries comprised of a variety of biologically relevant templates. Representative examples will also be given demonstrating the successful impact of MCR combinatorial methods at different stages of the lead discovery, lead optimization and pre-clinical process development arenas. This will include applications spanning biological tools, natural products and natural product-like diversity, traditional small molecule and 'biotech' therapeutics respectively. In particular, this review will focus on applications of isocyanide based MCR (IMCR) reactions.

... read more

889 Citations

Journal ArticleDOI: 10.1055/S-2003-40507
01 Jul 2003-Synthesis
Abstract: Following the increased interest from the pharmaceutical industry for the generation of diverse libraries of heterocyclic compounds, scientific efforts have become more and more focused on the development of novel multi-component procedures as a means of gaining rapid access to such compounds. Initially, the development of solid-phase procedures received considerable attention. However, current efforts are increasingly concerned with the development of solution-phase procedures. The latter will be the subject of discussion in this review, which aims to give an overview of the progress made in the past decade. After a general introduction, non-catalyzed, acid-catalyzed, and transition metal-catalyzed solution-phase multi-component procedures for the preparation of a wide range of heterocycles will be discussed. The last chapter discusses the role of cycloaddition reactions in the development of novel MCRs for the synthesis of heterocyclic compounds. In spite of their important role in the synthesis of heterocyclic compounds, MCRs involving isocyanides are not discussed in this review, since the topic has been exhaustively reviewed several times. 1 Introduction 2 Non-Catalyzed MCRs 3 Acid-Catalyzed MCRs 4 Transition Metal-Catalyzed or -Mediated MCRs 5 MCRs Involving Cycloaddition Reactions 6 Conclusions and Outlook.

... read more

836 Citations