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Scalability, cost, and feasibility of porous structures in gas capture are prerequisites for emerging materials to be promising in the industry. Herein, a simpler variant of Friedel−Crafts’ synthesis of highly porous covalent organic polymers (COPs) based on an unprecedented solvent‐mediated crosslinking is presented. Alkyl chlorides behave as both solvents and linkers in the presence of AlCl3. Studies on three classes of 18 different monomers using dichloromethane, chloroform, and 1,2‐dichloroethane lead to producing 29 new COPs (124−152). Polymers are characterized by Fourier‐transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) spectroscopy, elemental composition analysis, scanning electron microscope (SEM), thermogravimetric analysis (TGA), and porosity analyzer. The synthesized COPs exhibit structures from nonporous to highly porous morphologies with Brunauer–Emmett–Teller (BET) surface areas as high as 1685 m2 g−1. These COPs show high gas uptake toward CO2 (up to 4.71 mmol g−1 at 273 K, 1.1 bar), CH4 (up to 1.31 mmol g−1 at 273 K, 1.1 bar), and H2 (up to 2.02 wt% at 77 K, 1.1 bar). The findings point to significant potential in producing sustainable porous materials through simple and scalable methodology developed here.

Protected 2-O-benzyolated glycosyl formates were synthesized in one-step from the corresponding orthoester using formic acid as the sole reagent. Glucopyranosyl, mannopyranosyl and galactopyranosyl donors were synthesized and their glycosylation properties studied using model glycosyl acceptors of varied steric bulk and reactivity. Bismuth triflate was the preferred catalyst and KPF6 was used as an additive. The 1,2-trans-selectivities resulting from neighboring-group participation were excellent and the glycosylations were generally high-yielding.

Vinyl triflimides were only accessible recently and their chemistry is yet to be discovered. Herein, we describe a general, straightforward and atom‐economical synthesis of these materials from alkynes and triflimide. A vast array of terminal and internal alkynes with broad spectrum of functionalities could be employed to generate various di‐ and trisubstituted vinyl triflimides regiospecifically with high to specific stereoselectivity. Moreover, the protocol could be conducted on gram scale using terminal and internal alkynes. Preliminarily attempts to probe the unprecedented reactivity of vinyl triflimides revealed part of its chemical properties. [ABSTRACT FROM AUTHOR]

Nowadays, hypervalent iodine chemistry has remarkably advanced in parallel with the emergence of novel hypervalent iodine reagents. Hypervalent iodine reagents, due to their outstanding characteristics including rich reactivities, excellent chemoselectivity, stability, and environmental friendliness, are becoming more and more popular in the synthetic organic chemistry. In this Account, a number of recent elegant research works and our perspective on the future of hypervalent iodine chemistry is presented. 1 Introduction 2 Recent Advances and Discussion 2.1 Novel Reactivities of Hypervalent Iodine Reagents 2.2 Atom-Economical Reactions Promoted by Hypervalent Iodine Reagents 2.3 Other Applications of Hypervalent Iodine Reagents 2.4 The Applications of DFT Calculations in Elucidating Reaction Mechanism Involving Hypervalent Iodine Reagents 3 Outlook and Conclusion [ABSTRACT FROM AUTHOR]

A three-component reaction of 1 mol of arylhydrazonals with 2 mol of an active methylene compound is realized under pressure to obtained novel functionalized pyridazines with a 96% atom economy. The reaction of arylhydrazonals with active methylene compounds under pressure, ultrasound irradiation, and conventional heating is studied, and the reactions yields, and times are compared. The developed protocol is characterized by environmental friendliness, the use of low-cost catalysts and available starting materials, short reaction times, and high yields, and involves no column chromatography. The reaction offers up to a 96% atom economy and a 100% carbon capture. [ABSTRACT FROM AUTHOR]

The clever one‐pot combination of two macromolecular concepts, ring‐opening polymerization (ROP) and step‐growth polymerization (SGP), is demonstrated to be a simple, yet powerful tool to design a library of sequence‐controlled polymers with diverse and spatially regulated degradability functions. ROP and SGP occur sequentially at room temperature when the organocatalytic conditions are switched from basic to acidic, and each allows the encoding of specific degradable bonds. ROP controls the sequence length and position of the degradability functions, while SGP between the complementary vinyl ether and hydroxyl chain‐ends enables the formation of acetal bonds and high‐molar‐mass copolymers. The result is the rational combination of cleavable bonds prone to either bulk or surface erosion within the same macromolecule. The strategy is versatile and offers higher chemical diversity and level of control over the primary structure than current aliphatic polyesters or polycarbonates, while being simple, effective, and atom‐economical and having potential for scalability. [ABSTRACT FROM AUTHOR]

[Display omitted] A divergent transformation of ynamides with anthranils has been reported, which leads to the synthesis of various 7-acylindoles and 2-aminoquinolines in moderate to excellent yields. Indium(III) triflate is used as a cheap and readily available catalyst and the method exhibits high functional group tolerance. [ABSTRACT FROM AUTHOR]

A mild, catalytic, atom economical synthesis of imidazo[1,2-a]pyridines has been developed: catalytic PicAuCl2 in the presence of an acid produces a range imidazo[1,2-a]pyridines in good yield. This strategy is mild and forseen to be of particular use for the installation of stereogenic centers adjacent to the imidazo[1,2-a]pyridine ring without loss of enantiomeric excess.

Abstract Organic compounds that contain nitrogen are very important intermediates in pharmaceutical and chemical industry. Hydroamination is the reaction that can form C–N bond with high atom economy. The research progress in metals catalyzed hydroamination of alkenes and alkynes from the perspective of reaction mechanism is categorized and summarized.

One-pot, three-component reactions were utilized to obtain a series of new symmetrical bis(pyranopyrazoles) built around six rigid linkers in good yields and in the short durations under normal conditions. The structures of the prepared compounds were confirmed using their IR, 1H-NMR, 13C-NMR and ESI-MS spectral parameters. The bis(pyranopyrazoles) 3b and 3f exhibited significant antimicrobial action against Klebsiella pneumoniae, Fusarium oxysporum and Penicillium glabrum at a minimum inhibitory concentration (MIC) value of 3.12 μg mL-1, which is equivalent to the MIC of the standard drug. trans-Butene-linked bis(pyranopyrazole) 3f was also associated with a good radical scavenging activity similar to that of ascorbic acid (a standard antioxidant).

BACKGROUND: Production of biobased chemicals from renewable resources is a green starring approach that serves as a substitute to petroleum derivatives. Bioglycerol, with its growing production as a co‐product of biodiesel, is an attractive low‐cost feedstock for the synthesis of platform chemicals by microbial fermentation. 2,3‐butanediol (2,3‐BDO) is amongst the top biorefinery platform chemicals that can be produced by glycerol fermentation. RESULTS: The 'Circular Economy' concept is demonstrated by converting the by‐product bioglycerol using a cell‐free extract of Enterobacter aerogenes NCIM 2695 (National Collection of Industrial Microorganisms, NCIM), yielding 22 g L−1 2,3‐BDO, in 96 h, 98% atom economy and 0.4 g/g E factor. The cell‐free bioglycerol conversion to 2,3‐BDO was proved using a modified procedure for determining glycerol dehydrogenase enzyme assay by protein analysis and it was also shown to be cell‐bounded. CONCLUSION: Our study offers an effective utilization of the leftover material (i.e. cell‐free extract) that biocatalysed C3 to C4 diol, which adds value to the overall economics of the process using only crude glycerol (C3) itself as a fermentative medium. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

α‐Sulfenylated carbonyl compounds are important both as active pharmaceutical ingredients and as intermediates in organic synthesis. Owing to their relevance in synthetic organic chemistry, this Minireview focuses on assessing the most relevant synthetic procedures based on green chemistry metrics. The Minireview starts with the traditional routes and then focuses on more recently developed methodologies. These routes include sulfenylating reagents using organocatalysis, cross‐dehydrogenative couplings using in situ halogenations to prevent reactive intermediates in high concentrations, oxidative couplings using terminal oxidants such as DDQ or TEMPO, and redox‐neutral couplings using transition metal catalysis. These methodologies have been evaluated on the basis of atom economy, E factor, and the safety and toxicity of the transformations and the solvents used. Besides using green metrics to evaluate these novel methodologies, the synthetic utility is also assessed with regard to the availability of starting materials and the generality of the reactions. This Minireview aims to inspire researchers to apply green assessments to other methodologies and also for them to take measures to increase the greenness of their developed transformations. [ABSTRACT FROM AUTHOR]

An efficient, mild, and environment‐friendly methodology for the synthesis of azomethine chromophores through the reaction of 2‐aminobenzonitrile derivatives and acetophenones has been developed using CuCl (10 mol %) catalyst and toluene as a solvent under visible light irradiation. The reaction proceeds readily at room temperature under 20 W white LED with good to excellent yields in short reaction time. This methodology shows significant advantages such as environmentally benign reaction conditions, sustainability, enumerating tolerance of wide range of functional groups, cost‐effectiveness, high atom economy, short reaction time, and applicability for large‐scale synthesis. [ABSTRACT FROM AUTHOR]

To ensure a sustainable development, the "twelve principles of green chemistry" have been proposed for the field of synthetic organic chemistry. The stereoselective Ugi reaction is one of the most widely used reactions with high atom economy to prepare chiral a-bisamides and this reaction satisfies many of the green chemistry principles. The recent achievements in this reaction include one pot synthetic methodology, aqueous phase transformations and solvent free transformations even at ambient conditions. This review summarizes the progress recorded in this field over the past 20 years. [ABSTRACT FROM AUTHOR]

Organophosphorus chemistry is a broad field with multi‐dimensional applications in research area of organic, biology, drug design and agrochemicals. Conventional methods have been adopted extensively to access phosphorylated compounds that rely on the use of toxic, moisture sensitive phosphorylating agents and occur in the presence of oxidants, catalysts, as well as high temperatures and harsh conditions are required for complete transformations. However, recent progress has been made for phosphorylation reactions using electricity to introduce green and sustainable synthetic procedures. These reactions can be performed at mild conditions and proceed with excellent atom economy. Herein, we targeted electrochemical phosphorylation reactions with generation of new bonds such as C(sp3) −P, C(sp2) −P, O−P, N−P, S−P and Se−P. This review is aimed to offer an overview of recent developments in the synthetic methodology to easy access of organophosphorus compounds using electrochemistry. [ABSTRACT FROM AUTHOR]

Hypervalent iodine compounds, in particular aryl-λ3-iodanes, have been used extensively as electrophilic group-transfer reagents. Even though these compounds are superior substrates in terms of reactivity and stability, their utilization is accompanied by stoichiometric amounts of an aryl iodide as waste. This highly nonpolar side product can be tedious to separate from the desired target molecules and significantly reduces the overall atom efficiency of these transformations. In this short review, we want to give a brief summary of recently developed methods, in which this arising former waste is used as an additional reagent in cascade transformations to generate multiple substituted products in one step and with high atom efficiency.

We have developed a clean, atom-economical and environmentally friendly route for acceptorless dehydrogenation of amines to nitriles by combining a new dual N-heterocyclic carbene-nitrogen-phosphine ligand R(CNP) 2 (R = o -xylyl) with a ruthenium precursor [RuCl 2 (η6-C 6 H 6)] 2. In this system, the electronic and steric factors of amines had a negligible influence on the reaction and a broad range of functional groups were well tolerated. All of the investigated amines could be converted to nitriles in good yield of up to 99% with excellent selectivity. The unprecedented catalytic performance of this system is attributed to the synergistic effect of two ruthenium centers chelated by R(CNP) 2 and a plausible reaction mechanism is proposed according to the active species found via in situ NMR and HRMS. [ABSTRACT FROM AUTHOR]

The metal-free preparation of diazoalkanes through the ring rearrangement of bicyclic triazolines is reported here. Their use in 1,3-dipolar cycloaddition reactions with electron-withdrawing alkenes was investigated. This synthetic procedure allows differently substituted pyrazolines to be obtained in few steps and with high atom economy. [ABSTRACT FROM AUTHOR]

Metal-catalyzed reductive coupling processes have emerged as a powerful methodology for the introduction of molecular complexity from simple starting materials. These methods allow for an orthogonal approach to that of redox-neutral strategies for the formation of C–C bonds by enabling cross-coupling of starting materials not applicable to redox-neutral chemistry. This short review summarizes the most recent developments in the area of metal-catalyzed reductive coupling utilizing catalyst turnover by a stoichiometric reductant that becomes incorporated in the final product. 1 Introduction 2 Ni Catalysis 3 Cu Catalysis 4 Ru, Rh, and Ir Catalysis 4.1 Alkenes 4.2 1,3-Dienes 4.3 Allenes 4.4 Alkynes 4.5 Enynes 5 Fe, Co, and Mn Catalysis 6 Conclusion and Outlook [ABSTRACT FROM AUTHOR]

Benzylated glycosyl formates have been synthesized in one step from the corresponding hemiacetal or orthoester with formic acid as the sole reagent. The glycosyl formates are used as glycosyl donors under catalytic conditions with cheap metal catalysts based on iron or bismuth. A 13C NMR spectroscopic method is developed and evaluated for screening reactions conditions, giving precise information on the selectivity, yield, and byproducts formed. The major side reaction is transesterification, which gives the formylated acceptor and regenerates the hemiacetal. By using this approach, catalyst loadings and solvents are optimized and the scope of the glycosylation is evaluated for a variety of glycosyl donors and acceptors. A proof of concept for a traceless glycosylation, utilizing a dual‐purpose iron catalyst that catalyzes both glycosylation and dehydrogenation of formic acid, is also provided. [ABSTRACT FROM AUTHOR]

A synergistic rhodium‐ and Brønsted acid‐ catalyzed reaction of quinone imine ketals with diazo compounds to access multi‐substituted anilines is presented here. This reaction takes place through a process involving C−O bond cleavage, modification of the leaving alcoholic fragment, and selective reassembly of the reactive fragments. Moderate enantioselectivities are achieved when a chiral 1,1'‐bi(2‐naphthol)‐based phosphoric acid is used. [ABSTRACT FROM AUTHOR]

The selective aza-Michael addition at N1-position of indoles to 2-arylidenemalononitriles in the presence of potassium hydroxide is described. The salient features of this protocol are no transition-metal catalysts, mild conditions, high chemoselectivity, high atom economy, high yield and simple work-up procedures. [ABSTRACT FROM AUTHOR]

A total of 20 examples of 2-[(1 H -indol-1-yl)(aryl)methyl]-1,3-diphenylpropane-1,3-diones were efficiently synthesized by the aza-Michael addition at the N 1 position of indoles with 2-aroyl-1,3-diarylenones at room temperature in the presence of potassium hydroxide. The salient features of this protocol are no transition-metal catalysts, mild conditions, high chemoselectivity, high atom economy, high yields, and a simple work-up procedure. [ABSTRACT FROM AUTHOR]

Metalloporphyrins are involved in many and diverse applications that require the preparation of these compounds in an efficient manner, which nowadays, also involves taking into consideration sustainability issues. In this context, we use ball milling mechanochemistry and sonochemistry for the rational development of synthetic strategies for the sustainable preparation of metalloporphyrins. Zinc, copper, cobalt and palladium complexes of hydrophobic porphyrins were obtained in high yields and under mechanical action with a moderate excess of the metal salt, without any solvent or additive. Sonochemistry prove to be a good alternative for the preparation of metal complexes of water-soluble porphyrins in good yields and short reaction times. Both strategies have good sustainability scores, close to the ideal values, which is useful in comparing and helping to choose the more adequate method.

Diazocarbonyl compounds have found numerous applications in many areas of chemistry. Among the most developed fields of diazo chemistry is the preparation of azoles from diazo compounds. This approach represents a useful alternative to more conventional methods of the synthesis of azoles. A comprehensive review on the preparation of various azoles (oxazoles, thiazoles, imidazoles, pyrazoles, triazoles, and tetrazoles) from diazocarbonyl and related compounds is presented for the first time along with discussion of advantages and disadvantages of «diazo» approaches to azoles.

A large variety of dienes and alkenes can be derived from plants and used further for the production of fine chemicals or biologically active compounds. Herein, we have identified such dienes/alkenes, as well as their synthetic analogues, and presented a strategy for their conversion by atom‐economical cycloaddition reactions. The catalyst used for these conversions is derived from abundantly‐available aluminum metal in earth's crust, which has low toxicity, easy availability and low price in comparison to the transition metals. Astonishingly, the applications of aluminum‐based catalysts are underdeveloped in comparison to the d‐block metal analogues. Therefore, this review summarizes the developments in the field of cycloaddition reactions by using aluminum‐based catalysts, a pathway that can be pursued for developing "Sustainable Processes". [ABSTRACT FROM AUTHOR]

A facile, rapid, metal-free regioselective halogenation and thiocyanation of imidazo[1,2- a ]pyridine/pyrimidine heterocycles has been achieved under solvent-free reaction conditions. Halogenations and thiocyanation of the heterocycles could be accomplished by simple grinding of reactants and hypervalent iodine reagents with the corresponding alkali metal or ammonium salts. The method has been extrapolated to a cleaner synthesis of brominated imidazo[1,2- a ]pyridine/pyrimidine derivatives, starting from the corresponding heterocyclic amines and substituted α-bromoketones, utilising HBr generated in situ as the source of bromine. [ABSTRACT FROM AUTHOR]

A pyrazoline‐based organocatalyst was synthesized and used for the sequential formation of two structurally important heterocyclic compounds in one pot. A variety of substrates were found to be suitable for both arylation and alkyne‐carbonyl metathesis (ACM) reactions. Control reactions were performed to understand the catalytic pathway and a suitable mechanism was proposed. [ABSTRACT FROM AUTHOR]

A Na2HPO4‐catalyzed four‐component reaction between a ketone, malononitrile, S8 and formamide has been realized for the first time. This reaction provides a concise approach to thieno[2,3‐d]pyrimidin‐4‐amines, previously requiring 5 steps. The utility of this reaction was validated by preparing a multi‐targeted kinase inhibitor and an inhibitor of the NRF2 pathway with excellent atom‐ and step‐economy. [ABSTRACT FROM AUTHOR]

Catalytic functionalization/polymerization of castor oil‐derived undecenol yields an aliphatic polyester in a single step under mild conditions. The key to selective formation of linear high melting polyester is highly active carbonylation catalysts that at the same time do not undergo strong isomerization. Catalytic functionalization/polymerization of castor oil‐derived undecenol yields an aliphatic polyester in a single step under mild conditions. The key to selective formation of linear high melting polyesters is highly active carbonylation catalysts that at the same time do not undergo strong isomerization. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Firstly determining amorphous Fe 2 O 3 participates and improves [O] transfer cycle of CeO 2. • Achieving atom economy synthesis of imines under mild condition. • Much higher catalytic activity for synthesis of imine than reported CeO 2 catalyst. • Both preparation and catalytic application of the catalyst can be in large scale. Abstract CeO 2 based catalysts have been investigated in various catalytic reactions due to its unique reversible Ce3+/Ce4+ redox pair and physicochemical property, but its poor cycle efficiency and low reservoir limit its wide application in the fine chemicals industry. In this work, a novel amorphous Fe 2 O 3 modified CeO 2 catalytic system was developed by a facile co-precipitation method. The as-prepared samples were characterized in detail, and were employed for catalyzing the one-pot synthesis of imine from benzyl alcohol and aniline under air atmosphere at low temperature. The as-prepared sample with molar ratio of Fe:Ce = 8:2 dried at 100 °C (named Fe8Ce2-100) exhibited superhigh activity for atom economy synthesis of imine, which was much higher than the reported CeO 2 catalyst, even higher than some noble metal catalysts. It is worth noting that pure amorphous Fe 2 O 3 -100 could not catalyze this reaction at all, and both pure CeO 2 -100 and the mechanical mixed sample with the same molar ratio of Fe:Ce exhibited much more inferior catalytic activity than Fe8Ce2-100. Combining characterization results and the catalytic activities of different catalysts at various reaction conditions, the enhanced catalytic activity of Fe8Ce2-100 could be ascribed to the novel synergistic effect between CeO 2 and amorphous Fe 2 O 3. Amorphous Fe 2 O 3 plays the role of engine to greatly improve the [O] transfer cycle of Ce4+/Ce3+, as well as enhances the redox and amphoteric properties of the catalysts. This work firstly determines amorphous Fe 2 O 3 can participate and facilitate the catalytic cycle for organic reaction, and may provide a significant strategy for designing polymetallic oxide catalyst towards organic aerobic transformation. [ABSTRACT FROM AUTHOR]

Thioureas have emerged as effective hydrogen‐bonding catalysts over the last two decades, and they are broadly utilized in asymmetric catalysis. We report that achiral trisubstituted thioureas function as beneficial secondary ligands to CuI catalysts, thereby enabling highly diastereo‐ and enantioselective addition of α‐fluoronitriles to imines. The structure of the thiourea significantly affects the reaction outcome, and kinetic experiments indicate that the thioureas enhance the stereocontrol by binding to the CuI complex. The reaction products can be readily transformed into valuable β‐amino acid derivatives bearing a fluorinated tetrasubstituted stereogenic center. Achiral trisubstituted thioureas function as beneficial secondary ligands to CuI catalysts, thereby enabling the highly diastereo‐ and enantioselective addition of α‐fluoronitriles to imines. The structure of the thiourea significantly affects the reaction outcome, and kinetic experiments indicate that the thioureas enhance the stereocontrol by binding to the CuI complex. The reaction products can be transformed into valuable fluorinated β‐amino acid derivatives. [ABSTRACT FROM AUTHOR]

Herein, we established a straightforward synthetic route for biological relevant [1,2,4]triazolo[5,1‐b]quinazolin‐8(4H)one scaffolds using the group‐assisted purification (GAP) chemistry via one‐pot and three component reaction of 3‐Amino‐5‐methylthio‐1H‐1,2,4‐triazole (1), Aryl aldehyde(2 a–g), and 1,3‐cyclodione (3 a–b) using L‐proline and aqueous ethanol (1:1, v/v) as green catalyst and reaction media respectively. This work shows some key features such as practical low Environment factor (E‐factor) values, excellent atom economy, reaction mass efficiency, mild reaction condition, metal‐free synthesis, and no use of column chromatography. In preliminary biological screening, the compounds, 2‐(methylthio)‐9‐(4‐nitrophenyl)‐5,6,7,9‐tetrahydro‐[1,2,4]triazolo[5,1‐b]quinazolin‐8(4H)‐one (4 i) and 6,6‐dimethyl‐2‐(methylthio)‐9‐(pyridin‐4‐yl)‐5,6,7,9‐tetrahydro‐[1,2,4]triazolo[5,1‐b]quinazolin‐8(4H)‐one (4 l) were found most potent against Gram‐negative bacteria (E. coli) than the standard drugs ampicillin and chloramphenicol. Moreover, compounds 2‐(methylthio)‐9‐phenyl‐5,6,7,9‐tetrahydro‐[1,2,4]triazolo[5,1‐b]quinazolin‐8(4H)‐one (4 a) and 9‐(4‐methoxyphenyl)‐6,6‐dimethyl‐2‐(methylthio)‐5,6,7,9‐tetrahydro‐[1,2,4]triazolo[5,1‐b]quinazolin‐8(4H)‐one (4 f) exhibited excellent potency in comparison with the standard drugs ampicillin, chloramphenicol, and ciprofloxacin against Gram‐positive bacteria (S. aeruginosa and S. pneumoniae). In antifungal screening compounds, 9‐(4‐methoxyphenyl)‐2‐(methylthio)‐5,6,7,9‐tetrahydro‐[1,2,4]triazolo[5,1‐b]quinazolin‐8(4H)‐one (4 e) and 2‐(methylthio)‐9‐(4‐nitrophenyl)‐5,6,7,9‐tetrahydro‐[1,2,4]triazolo[5,1‐b]quinazolin‐8(4H)‐one (4 i) efficiently inhibited C. albicans fungi strain than that of standard drug griseofulvin. Noteworthy compounds 6,6‐dimethyl‐2‐(methylthio)‐9‐phenyl‐5,6,7,9‐tetrahydro‐[1,2,4]triazolo[5,1‐b]quinazolin‐8(4H)‐one (4 b), 9‐(4‐chlorophenyl)‐6,6‐dimethyl‐2‐(methylthio)‐5,6,7,9‐tetrahydro‐[1,2,4]triazolo[5,1‐b]quinazolin‐8(4H)‐one (4 d), and 2‐(methylthio)‐9‐(pyridin‐4‐yl)‐5,6,7,9‐tetrahydro‐[1,2,4]triazolo[5,1‐b]quinazolin‐8(4H)‐one (4 k) were exhibited better potency against M. Tuberculosis. Synopsis By holding the green chemistry concept, we explored one‐pot synthesis [1,2,4]triazolo[5,1‐b]quinazolin‐8(4H)one scaffolds. Moreover, all the newly synthesized compounds were tested for their antimicrobial and anti tuberculosis activities. Noteworthy, majority of compounds were exhibited better antimicrobial and anti tuberculosis activities. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A simplified Hummers method was developed to fabricate MnO 2 /GO composite. • Exceed 50% of KMnO 4 amount, 50% of reagents and 1/3 of preparation time were cut. • High reaction temperature was avoid. • The method is green, low cost, eco-friendly, time and energy saving, easy to scale up. Abstract In the work, we demonstrated the possibility of directly using the existing KMnO 4 as Mn precursor and graphite as the carbon precursor in Hummers method to decorate MnO 2 nanomaterials over graphene oxide (GO). Nanorod-like α-MnO 2 in the form of single crystal were found closely decorated over GO. The MnO 2 content could be easily adjusted from 45% to 18% by decrease the amount of KMnO 4 from 15.0 g to 7.5 g. Compared with the reported work, the developed simplified Hummers method in this work could better utilize KMnO 4 by cutting exceed 50% of KMnO 4 amount, cut the reagents especially some hazardous reagents from 6–8 items to 3 items, cut 1/3 of the preparation time, avoid high temperature reaction. All those advantages make the simplified Hummers method green, low cost, eco-friendly, time and energy saving, which are beneficial to the industrialization of the MnO 2 /GO composite. The MnO 2 /GO composite showed good performance in the degradation of methylene blue with the assistance of H 2 O 2. [ABSTRACT FROM AUTHOR]

A new way of developing novel synthesis strategies for the construction of monocyclic rings found in organic molecules is presented. The method is based on the visual application of integer partitioning to chemical structures. Two problems are addressed: (1) the determination of the total number of possible ways to construct a given ring by 2-, 3-, and 4-component couplings; and (2) the systematic enumeration of those possibilities. The results of the method are illustrated using cyclohexanone, pyrazole, and the Biginelli adduct as target ring systems with a view to discover new and greener strategies for their construction using multicomponent reactions. The application of the method is also extended to various heterocycles found in many natural products and pharmaceuticals.

This paper makes a parallel between the original route versus the green route of Ibuprofen (non-steroidal anti-inflammatory drugs most commonly recommended) synthesis. The original route contained six steps with stoichiometric reagents (some reagents are very toxic: hydrochloric acid, ammonia), a lot of intermediate products, relatively low atom efficiency equal to 40.04% and substantial inorganic salt formation (aluminium trichloride hydrate). The green route of Ibuprofen synthesis developed only three steps, a lower amount of waste and by-products (only acetic acid that can be used for another applications) and an atom efficiency of 77.44%. The green route for Ibuprofen synthesis is an exquisite example of a simple and elegant chemical/pharmaceutical manufacturing process and the nearly complete atom utilization of this streamlined process truly makes it a wasteminimizing, environmentally friendly technology.