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An aqueous photocatalytic system was designed by merging visible-light photoredox catalysis with micellar catalysis. Eosin B, an organic dye, was utilized as the photocatalyst, and Triton X-100 was employed as the surfactant; both are inexpensive and commercially available. This clean and energy-saving catalytic system enables photocatalytic reactions of the diazonium ion generated in situ to proceed smoothly in water without any co-solvents or additives at room temperature.

A newly developed, facile and sustainable strategy, in which zinc salt, melamine and ethyl cellulose are applied as pore-forming agent, nitrogen and carbon source respectively, has been disclosed for the synthesis of Fe/N-codoped carbon materials. This material exhibits excellent catalytic efficiency towards N–H carbene insertion reaction for the synthesis of unnatural amino acid derivatives. Fe/FeOx nanoparticles tranfer electrons to N-doped carbon owing to the Mott-Schottky Effect, which is beneficial to the formation of iron carbene intermediate. N-doping can offer more Lewis base sites, which promotes the proton transfer process. Fe/FeOx nanoparticles are coated with graphitic carbon, thereby avoiding the loss and deactivation of iron sites in this material. Therefore, this material can be reused at least four times without significant loss in activity.

Various indolizines are synthesized through one-pot, two-step 1,3-dipolar cycloadditions in recyclable [Omim]Br with high yields and a broad substrate scope. The promotion of noncovalent interactions between ionic liquids and substrates or intermediates on the reaction is discovered on the basis of the results of control and NMR experiments. Moreover, the 3-arylindolizines can also be prepared from low-activity arylmethylpyridinium ylides in the protocol.

Vesicles self-assembled from an aqueous PEGylated surfactant ionic liquid solution can be applied for stabilizing palladium nanoparticles, which prove to be an efficient catalytic system for chemoselective hydrogen transfer of nitroarenes using hydrazine hydrate as a hydrogen source. The particle sizes of vesicles are decreased with the increase of ionic liquid's concentrations and relatively small particle sizes are beneficial to the reduction. Moreover, the aqueous catalytic system still stays in reactor by simple extraction, and is reused without further treatment.

A one-pot synthesis of β-amino α,α-difluoro ketones is developed without any additives. Through a series of control experiments we found that water plays a crucial and indispensable role. The hydrogen bond between water and fluorinated enol silyl ether has a significant impact on the addition reaction.

Condensation poses a serious challenge to the mechanical durability and sustainable development of modern buildings in tropical environment. Moisture condensation and absorption in architecture causes inconvenience and requires extra maintenance measures. A mechanically durable anti-condensation coating that displays very low affinity with moisture is promising for applications on wall and ceiling of buildings. A main challenge in the fabrication of anti-condensation surface lies with the requirements of preventing water accumulation on the surface while maintaining the breathability of substrate. In this study, a breathable anti-condensation coating has been developed on cementitious substrates based on bio-based epoxy resins. The coating presented water repellency and a condensation delay time of 50 min when compared to the uncoated counterpart at a sub-cooled temperature of 8 °C. The excellent tolerance against condensation was verified after 200 h continuous condensation test according to ISO 6270 standard. The coating also displayed good breathability and moisture resistance, which are key to the inhibition of bacteria growth and structural deterioration in architecture. Moreover, the superhydrophobic sample demonstrated a 9.7% increase in thermal conductivity over the uncoated substrate. Mechanical tests showed good adhesion between the coating and the substrate. The coated area of cementitious substrate maintained its superhydrophobicity even after the bulk coating was removed. The coating also displayed superior mechanical durability over the state-of-the-art anti-condensation coatings. The reported method provides a practically useful and environmentally friendly solution to mitigate water absorption problem of concrete based architectures. Nanyang Technological University Financial support from Surbana Jurong – NTU Corp Lab is greatly acknowledged.

An acid-promoted protocol has been developed to achieve the transition-metal- and phosphorus-free electrophilic trifluoromethylthiolation of indoles using sodium trifluoromethanesulfinates in an imidazolium-based ionic liquid ([Hmim]Br). [Hmim]Br not only acts as a recyclable solvent, but also as the reductant in this transformation. The advantages of this chemistry include simple operation, use of a recyclable solvent, avoidance of transition-metal and phosphorus, and gram-scale synthesis.

A one-pot, catalyst-free route to spiro[dihydroquinoline-naphthofuranone] compounds from isatins through ring-opening and cyclization processes in water is disclosed. Hydrogen-bonding effects of water proved to be the key factor to accelerate the transformation. In addition, the chemistry provides several advantages including that it is free of organic solvents, a simple operation, and a gram-scale synthesis and uses inexpensive reagents and a recyclable reaction medium.

A radical-mediated approach has been introduced for the C-S bond activation of arylalkenyl sulfides. The protocol provides an efficient approach for the generation of various alkenes including alkenyl silanes, sulfones, phosphine oxides, and nitroolefins. In most cases, these radical substitutions are performed under metal-free conditions with stereospecificity.

An efficient, recyclable Pd–Cu bimetallic nanoparticle catalyst has been prepared, which exhibits superior activity and selectivity toward the hydrosilylation of internal and terminal alkynes under mild reaction conditions with a low catalyst loading. Distinct enhancement in catalytic performance is observed when compared with traditional monometallic catalysts, and the composition of BMNPs is found to be crucial in both selectivity and yield. This kind of elevation in catalytic performance can be ascribed to the enrichment of active sites (Pd) on the catalyst surface and a phenomenon collectively referred to as “synergistic effects”. The successful application of BMNPs as catalysts in the alkyne hydrosilylation opens up new possibilities for the excavation of the value of bimetallic nanoparticles in catalysts’ development for sustainable chemistry.

A MIL-100(Fe) supported Pd–Ni BMNP catalyst has been fabricated, and the catalyst exhibits superior catalytic performance toward the intramolecular transfer hydrogenolysis of lignin model compounds and organosolv lignin. Alcoholic groups (CαH-OH) of lignin were exploited as the hydrogen source, and selective cleavage of β-O-4 linkages in lignin was realized without an extra hydrogen donor. This protocol was suitable for organosolv lignin as well as model compounds; several phenols and functionalized acetophenones were detected when extracted lignin was treated in our system. The catalyst exhibits outstanding catalytic stability during the reaction process, which can be ascribed to the porous structure and the strong water stability of MIL-100(Fe). The excellent catalytic performance of Pd1Ni4/MIL-100(Fe) highlights the “synergistic effect” between the BMNPs and the functional synergy between MNPs and MOFs, and our work shows the bright future of BMNPs and MOFs in the development of catalysts for sustainable chemistry.

A practical sliver-catalyzed fluoroalkylation of aryl-, heteroaryl- and alkylthiols has been developed. The reaction has a good functional-group tolerance and excellent selectivity. A variety of stable and solid fluoroalkanesulfinates including di- and perfluoroalkanesulfinates can be employed. This methodology provides a straightforward and streamlined access to perfluoroalkylthiolated organic molecules. Figure options Download full-size image Download high-quality image (173 K) Download as PowerPoint slide

A transition-metal-free direct trifluoromethylthiolation of indole derivatives under mild conditions has been developed. Commercially available sodium trifluoromethanesulfinate (CF3SO2Na) acts as the trifluoromethylthiolating reagent, which is cheap, stable and easy to handle. The substrate scope of this protocol could also be expanded to pyrroles and enamines.

Regioselective arylthiolations of aromatic amines, arenols and ketones via C–H bond functionalization have been achieved with I2 and PPh3 in an aqueous system, whereby arylsulfenyl radicals are in situ generated from odorless sodium arylsulfinates. The arylsulfenyl radicals can react with free anilines containing electron-withdrawing groups and complex substrates (estrone and progesterone). Further experiments and quantum chemical calculations were also performed to deduce a mechanism for the formation of arylsulfenyl radicals.

Highly dispread Ni-Co bimetallic nanoparticles (Ni-Co BMNPs) are synthesized and applied as an efficient catalyst in the chemoselective transfer hydrogenation of nitroarenes (CTH) using hydrazine hydrate as the hydrogen donor. The BMNPs can efficiently catalyze the reduction reaction without any additives under mild conditions with high TOF. Significantly higher activity is achieved when compared with corresponding single-component catalysts, optimal composition of the Ni-Co BMNPs was screened which was proved to be crucial in both the selectivity and yields. Excellent performance of Ni-Co BMNPs can be ascribed to the improved dispersion of active sites on the BMNPs surface (compared with Ni NPs) and the electron transfer from cobalt to nickel.

The nucleophilic aromatic substitution reaction and thia-Michael addition using thiourea as an odorless, cheap, and easy-to-handle sulfur source in water are described, which can be used to teach upper-division undergraduates the role of thiourea in the formation of C–S bonds and the principles of green chemistry. The use of a cheap, nontoxic surfactant Triton X-100 proves to promote both reactions obviously by contrast reactions. The structures of products obtained from the two reactions by students are determined via analyzing nuclear magnetic resonance spectral data. Students also propose the mechanisms of the two reactions and point out the green and nongreen aspects of this experiment.

The fluorine-containing organic compounds are becoming privileged in medicinal chemistry. Described herein is an efficient and environmental friendly method for the synthesis of the gem-difluoromethylene azo compounds without any additives, and the hydrogen bond between water and fluorinated enol silyl ether slightly promote the reaction.

Hf-MOF-808 exhibits excellent activity and specific selectivity on the hydrogenation of carbonyl compounds via a hydrogen transfer strategy. Its superior activity than other Hf-MOFs is attributed to its poor crystallinity, defects and large specific surface area, thereby containing more Lewis acid-base sites which promote this reaction. Density functional theory (DFT) computations are performed to explore the catalytic mechanism. The results indicate that alcohol and ketone fill the defects of Hf-MOF to form a six-membered ring transition state (TS) complex, in which Hf as the center of Lewis stearic acid coordinates with the oxygen of the substrate molecule, thus effectively promoting hydrogen transfer process. Other reactive groups, such as –NO2, C = C, -CN, of inadequate hardness or large steric hindrance are difficult to coordinate with Hf, thus weakening their catalytic effect, which explains the specific selectivity Hf-MOF-808 for reducing the carbonyl group.

The electronic metal-support interactions that are well-known in metal-loaded metal oxides, are also disclosed in Pd@MOFs. According to the experimental and calculation results, the superior catalytic performance of Pd@MIL-125(Ti) is mainly attributed to the higher ratio of Pd0/Pd2+ and electronic density of Pd nanoparticles which are triggered by stronger Lewis base sites and less Lewis acid sites of MIL-125(Ti) respectively. Therefore, the Pd@MIL-125(Ti) catalyzed hydrogenation of nitroarenes and alkenes can be carried out in water using low Pd usage (0.12 mol%) with excellent selectivity under mild conditions (room temperature, 1 atm H2). Moreover, the aqueous catalytic system still stays in reactor by simple extraction, and can be reused without further treatment, thus resulting in low environmental factor.

In this study, we conduct comprehensive experimental and theoretical investigations on the hydrogen evolution reaction (HER) preformation of FeP electrode in acidic and alkaline solutions. Theoretically, bulk Fe-O bond is unfavorable, but surface Fe-O bond is favorable and plays a negative role for HER. The presence of oxygen bonds (native or formed during reaction) is the root source of the reduced HER activity. Surface treatment in 37% HCl solution removes the oxide layer and significantly improves the HER performance, especially in alkaline solution. After etching, the overpotentials in 0.5 M H2SO4 are 79 and 95 mV at 10 and 20 mA cm−2, respectively. The ones in 1 M KOH are 95 and 102 mV at 10 and 20 mA cm−2, respectively. Long-term instability in alkaline solution is caused by the presence of oxygen in the electrolyte. Good stability can be realized by removing oxygen from the solution. Ministry of Education (MOE) National Research Foundation (NRF) Accepted version Financial support from following is gratefully acknowledged: Ministry of Education - Singapore (RG15/16, RG16/18), National Research Foundation, Singapore (SINBERISE), National Natural Science Foundation of China (No. 21676216).

Cellulose with tailorable hydrophilicity/hydrophobicity were synthesized by grafting F-containing groups and utilized as supports for palladium nanoparticles. The obtained catalysts were applied in the synthesis of N-phenylhydroxylamine from controllable reduction of nitrobenzene. Unexpectedly high conversion and selectivity could be achieved with 25 ppm Pd catalyst at room temperature in water. The precise modification of the catalyst surface is crucial to realize this targeted transformation. Further investigation indicated that modified cellulose with a more hydrophobic surface would favour the adsorption of nitrobenzene over N-phenylhydroxylamine thus prevent full hydrogenation to aniline.

The children with acute respiratory distress syndrome (ARDS) usually require ventilatory support treatment. At present, lung protective ventilation strategy is recommended for the treatment of ARDS. Extracorporeal membrane oxygenation (ECMO) can improve oxygenation and remove carbon dioxide by extracorporeal circuit, and can partially or completely take over cardiopulmonary function. ECMO support showed many advantages in treating severe ARDS, such as reducing ventilator-induced lung injury and correcting hypoxemia. Over the past few years, there has been an increase in the use of ECMO for ARDS in children. This paper reviews the applications of ECMO for the treatment of ARDS in children.

This article reviewed the Consensus Recommendations on Pediatric Acute Respiratory Distress Syndrome (ARDS) from the Pediatric Acute Lung Injury Consensus Conference in 2015 and the literature related to drug management of ARDS. The main points of drug management of pediatric ARDS were summarized.

Acute respiratory distress syndrome (ARDS) is a common critical illness in children and has high incidence and mortality rates among critically ill pediatric patients. Noninvasive ventilation has become a common treatment method for ARDS because of its unique features. This article reviews the research status in the application of noninvasive ventilation in children with ARDS.

Pediatric acute respiratory distress syndrome (ARDS) is an important cause of deaths in critically ill children admitted to the pediatric intensive care unit. Although lung-protective ventilation improves the prognosis of pediatric ARDS, the mortality rate of children with moderate or severe ARDS is still high. Given that the epidemiology, treatment, and prognosis of pediatric ARDS are different from those of adult ARDS, pediatric ARDS was first defined in the 2015 Pediatric Acute Lung Injury Consensus Conference. Early diagnosis and appropriate clinical management of ARDS are still great challenges for pediatric critical care medicine. This paper focuses on the definition, epidemiology, and management of pediatric ARDS.

An efficient sulfonylation of activated alkenes with sodium arylsulfinates in water at room temperature is introduced. Water proves to enhance more obviously the transformation compared with other solvents. The quantum chemical calculations suggest that the protonation of alkenes is the key step of the reaction, which could be accelerated by polarity effects of water. Moreover, water can polarize and stabilize the charged intermediates based on the results of quantum calculations.

The β-O-4 linkage in lignin can be selectively cleaved by Pd–Ni bimetallic nanoparticles supported on ZrO2 using hydrogen gas as the hydrogen donor under ambient pressure and neutral conditions. Conspicuous enhancement in activity is observed compared with single nickel and palladium catalysts based on the results of experiments and characterization. Moreover, hydrogenation of the produced phenols is tuned by adjusting the amount of NaBH4. The catalyst can be reused over ten times in the model reaction and over five times in the hydrogenolysis of lignin without an obvious change in activity and selectivity.

A mild, simple and metal-free radical [4 + 2] benzannulation for the generation of phenanthrenes has been developed. A substoichiometric reductant, ascorbic acid (vitamin C), is harnessed as the radical initiator. This method has a broad substrate scope, and various substituted phenanthrenes were obtained in moderate to good yields at room temperature without irradiation.

A facile aromatic nucleophilic substitution (SNAr) reaction in recyclable [Omim]Br under relatively mild conditions has been described. An electrophile–nucleophile dual activation by [Omim]Br is also discovered based on control experiments, 1H NMR and IR spectroscopies. This chemistry provides an efficient and metal-free approach for the generation of Caryl–X (XS, N, O) bonds, many of which are significant synthetic intermediates or drugs, making this methodology attractive to both synthetic and medicinal chemistry.

A method for photocatalytic oxidative coupling of diaryl phosphine oxide and arylacetylene under mild conditions was developed. Rhodamine B, an inexpensive and commercially available organic dye, was used as the photocatalyst. This protocol realizes a regioselective 1,2-difunctionalization of arylacetylenes and provides a metal-free access toward a series of β-ketophosphine oxides.

An efficient and highly regioselective protocol for copper(II)-catalyzed remote C–H fluoroalkylation of 8-aminoquinoline amides with RfSO2Na (Rf = CF3, CF2H, C4F9, C5F11, and C6F13) is described. This reaction provides an effective strategy for the direct construction of fluorine-containing six-membered heteroaromatic core structures.

A selective and facile trifluoromethylation process for a wide range of thiophenols and thiols under metal free conditions has been developed using two simple and safe solids, sodium trifluoro-methanesulfinate and iodine pentoxide, via the radical process.

Effective hydrodeoxygenation (HDO) of dibenzofuran (DBF) catalyzed by a bimetallic nickel/platinum (Ni/Pt) catalyst in water was demonstrated at 200 °C and 1.2 MPa hydrogen (H2) pressure. The bimetallic catalysts prepared by a wet chemical method exhibit prominent activity that overcomes the limitations of use of a single Ni or Pt metal catalyst. The yield of HDO products can be up to 90%. Reaction results indicate that the conversion of DBF was affected by the reaction temperature and H2 pressure. The deoxygenation selectivity was strongly dependent on reaction temperature. The reaction pathway is also proposed.

A highly efficient dimethylformamide (DMF)-promoted decarboxylative trifluoromethylation of α,β-unsaturated carboxylic acids with Togni (II) reagent under metal-free conditions has been developed. The reactions showed good yields, high stereoselectivities and excellent functional group tolerance. Mechanistic studies confirmed that free-radical processes were involved in this system since the CF3 radical had been clearly trapped by scavengers. This method has been extended to the denitrative trifluoromethylation of β-nitrostyrenes in the presence of an iron(III) catalyst.

A new method for CF3SO2Na-based direct trifluoromethylthiolation of C(sp(2))-H bonds has been developed. CF3SSCF3 is generated in situ from cheap and easy-to-handle CF3SO2Na, and in the presence of CuCl can be used for electrophilic trifluoromethylthiolation of indoles, pyrroles, and enamines. The method has been extended to perfluoroalkylthiolation reactions using RfSO2Na.

The direct C-3 alkylation of indoles with primary and secondary alcohols through the combination of KOH and an N-heterocyclic carbene is described. The KOH/NHC-catalysed system can give desired C-3 alkylated indoles with high selectivity in moderate to excellent yields. Moreover, this process has obvious advantages such as high atom economy and the absence of a metal source.

A mild, metal-free synthesis of aryl sulfides has been disclosed. Aryl diazonium ion was generated by the in situ nitrosation of aniline, and it was reduced by ascorbic acid (vitamin C) to form aryl radical, which underwent a thiolation with disulfide to yield aryl sulfide. The reaction proceeded smoothly without heating or irradiation. This strategy was also expanded to the synthesis of aryl selenides.

Pd-based nanomaterials have been considered as an effective catalyst for formic acid electrooxidation reaction (FAOR). Herein, we reported two types of polyaniline (PANI)-promoted Pd catalysts. One was an nPANI/Pd electrocatalyst prepared by the electropolymerization of aniline and the electrodeposition of Pd. The other was a Pd/C/nPANI catalyst prepared by the direct electropolymerization of aniline on a commercial Pd/C catalyst. The results show that PANI alone has no catalytic activity for FAOR; however, PANI can exhibit a significant promoting effect to Pd. The current densities of FAOR on the Pd catalysts with a PANI coating show a significant increase compared with that of the Pd reference catalyst without PANI as a promoter. The promoting effects of PANI are strongly dependent on the electropolymerization potential cycles (n). The highest catalytic activities for FAOR of all the nPANI/Pd and Pd/C/nPANI catalysts were those of 15PANI/Pd and Pd/C/20PANI. The mass-specific activity (MSA) of Pd in 15PANI/Pd was 7.5 times that of the Pd catalyst, and the MSA and intrinsic activity of Pd/C/20PANI were 2.3 and 3.3 times that of the Pd/C catalyst, respectively. The enhanced performance of Pd catalysts is proposed as an electronic effect between Pd nanoparticles and PANI.

An unprecedented C–S formation protocol via the direct oxidative C(sp3)–H bond thioesterification of isochroman under metal-free conditions was developed. A series of isochroman derivatives could be afforded efficiently by the green, simple, and atom-economical method.

A new tandem catalytic process has been established for the synthesis of quinolines. This process utilizes the [IrCp*Cl2]2/KOH catalyzed isomerization/cyclization of allylic alcohols with 2-aminobenzyl alcohol. Both the secondary and primary allylic alcohols were investigated in this catalytic system to afford different substituted quinoline derivatives in moderate to good yields. A mechanism study showed the reaction following a tandem process integrating isomerization of allylic alcohols and oxidative cyclization of 2-aminobenzyl alcohol.

A newly developed protocol for the reduction of nitroarenes using thiourea as the hydrogen source is described. The method is simple, inexpensive and easily applicable to the preparation of a variety of substituted anilines with high yields and selectivity. In contrast to traditional hydrogenation methods, this chemistry does not require a catalyst, elaborated work-up procedures, or the use of high-pressure equipment.

A simple homogeneous catalyst system based on commercially available [IrCp*Cl2]2 has been developed for the conjugate reduction of α,β-unsaturated ketones. Under the optimized conditions, a wide range of α,β-unsaturated ketones were reduced to saturated ketones in 83–98% yield. While switching the base from K2CO3 to KOH, saturated alcohols was selectively obtained.

Iridium-catalyzed methylation of indoles and pyrroles using methanol as the methylating agent was achieved. This transformation takes place via a borrowing hydrogen methodology under an air atmosphere, which constitutes a direct route to 3-methyl-indoles and methyl-pyrroles.

A newly developed C–S bond formation process via acid-catalyzed thia-Michael addition has been demonstrated. The protocol, in which Bunte salts generated from odorless and inexpensive sodium thiosulfate and organic halides are used as the thiol precursors, provides an efficient approach for the synthesis of β-sulfido carbonyl compounds.

An unprecedented C-S formation method via direct oxidative C(sp(3))-H bond functionalization and C-O cleavage of benzylic ethers was developed. Various thioesters including thioester structure containing drug intermediates could be achieved by this convenient, metal and base free method in satisfactory yields.

An approach for the synthesis of isochroman derivatives via direct C(sp3)–H bond and N–H bond coupling is described. The C–N (amine or amide) and CN (imidate) products can be selectively achieved by controlling the amount of oxidants. Moreover, this metal- and base-free protocol is simple, easy-to-handle, and atom-economical which may have potential application in drug synthesis.

A simple and general homogeneous catalyst system composed of commercially available [Ir(cod)Cl]2 and 1,10-phenanthroline has been developed for the selective transfer hydrogenation of nitroarenes to anilines. It utilized the readily accessible 2-propanol as a hydrogen donor and had wide substrate scope. A careful mechanistic investigation through real-time detection and a series of controlled experiments with possible intermediates was also carried out, which showed that the transformation proceeds via both phenylhydroxylamine and azobenzene intermediates and the reduction of hydrazobenzene leading to aniline might be the rate-determining step.

A new protocol for achieving the phosphination of arenes, arenols and thiols has been disclosed. This chemistry, in which diaryl(((trifluoromethyl)sulfonyl)oxy)phosphines as a kind of electrophilic phosphination reagents are in situ generated from diarylphosphine oxides, provides an efficient and mild approach for the synthesis of aromatic organophosphorus compounds.

A mild and efficient method for the photocatalytic radical cyclization of α-halo hydrazones with β-ketocarbonyls has been described. This strategy provides a potential protocol for the construction of functionalized 4,5-dihydropyrazoles in moderate to high yields.

An acid-induced protocol for the chemoselective arylthiolations of electron-rich arenes in ionic liquids from sodium arylsulfinates is introduced. The chemistry, in which [Hmim]Br (heaxylmethylimidazolium bromide) is used as both a solvent and a reducer, provides several advantages including odorless and simple operation, inexpensive reagents, recyclable solvents and gram-scale synthesis.