An alternate aqueous phase synthesis of the Pt3Co/C catalyst towards efficient oxygen reduction reaction

Carbon supported Pt-Co alloys are among the most promising electrocatalysts towards oxygen reduction reaction(ORR)for the application in low temperature fuel cells and beyond,thus their facile and green synthesis is highly demanded.Herein we initially report an alternate aqueous phase one-pot synthesis of such catalysts(containing nominally ca.20 wt.%Pt)based on dimethylamine borane(DMAB)reduction.The as-obtained electrocatalyst(denoted as Pt3Co/C-DMAB)is compared with the ones obtained by NaBH4 and N2H4·H2O reduction(denoted as Pt3Co/C-NaBH4 and Pt3Co/C-N2H4·H2O,respectively)as well as a commercial Pt/C,in terms of the structure and electrocatalytic property.It turns out that Pt3Co/C-DMAB exhibits the highest ORR performance among all the tested samples in an O2-saturated 0.1 mol/L HClO4,with the mass activity(specific activity)ca.4(6)times as large as that for Pt/C.After 10000 cycles of the accelerated degradation test,the half-wave potential for ORR on Pt3Co/C-DMAB decreases only by 4 mV,in contrast to 24 mV for that on Pt/C.Pt3Co/C-NaBH4 or Pt3Co/C-N2H4·H2O shows a specific activity comparable to that for Pt3Co/C-DMAB,but a mass activity similar to that for Pt/C.ICP-AES,TEM,XRD and XPS characterizations indicate that Pt3Co nanoparticles are well-dispersed and alloyed with a mean particle size of ca.3.4±0.4 nm,contributing to the prominent electrocatalytic performance of Pt3Co/C-DMAB.This simple aqueous synthetic route may provide an alternate opportunity for developing efficient practical electrocatalysts for ORR.

A Solid Phase Synthesis of Chalcones by Claisen-Schmidt Condensations

In order to accelerate the development of relatively inexpensive antimalarials that are effective against chloroquine-resistant strains of Plasmodium falciparum, a methodology for the solid phase synthesis of chalcone (1, 3-diphenyl-2-propen-1-one) analogues in reasonably high yields has been developed.

A Facile Solid-phase Synthesis of 3-Carboxycoumarins

Carboxycoumsrins were synthesized via the solid phase synthesis conviently. The resin bound cyclic malonic ester reacted with o-methoxy or o-hydroxybenzaldehydes. Then cyclization was processed under H2SO4 to afford the products in excellent purities and yields.

AQUEOUS PHASE SYNTHESIS OF(RC_5H_4)_2Ti(O_2CC_6H_4X)_2

Nine complexes(RC_5H_4)_2Ti(O_2CC_6H_4X)_2(R=H,CH_3;X=H,o-Cl,o-OH, o-NH_2,o-NHPh)have been conveniently prepared by the reaction of (RC_5H_4)_2TiCl_2 with 2 equiv.sodium salts of corresponding carboxylic acid in aqueous solution containing acetylacetone.The carboxylate ligands in the complexes coordinate to titanium atom in monodentate mode.

Liquid-phase synthesis of Li_(2)S and Li_(3)PS_(4) with lithium-based organic solutions

Sulfide solid electrolytes are widely regarded as one of the most promising technical routes to realize all-solid-state batteries(ASSBs)due to their high ionic conductivity and favorable deformability.However,the relatively high price of the crucial starting material,Li_(2)S,results in high costs of sulfide solid electrolytes,limiting their practical application in ASSBs.To solve this problem,we develop a new synthesis route of Li_(2)S via liquid-phase synthesis method,employing lithium and biphenyl in 1,2-dimethoxyethane(DME)ether solvent to form a lithium solution as the lithium precursor.Because of the comparatively strong reducibility of the lithium solution,its reaction with sulfur proceeds effectively even at room temperature.This new synthesis route of Li_(2)S starts with cheap precursors of lithium,sulfur,biphenyl and DME solvent,and the only remaining byproduct(DME solution of biphenyl)after the collection of Li_(2)S product can be recycled and reused.Besides,the reaction can proceed effectively at room temperature with mild condition,reducing energy cost to a great extent.The as-synthesized Li_(2)S owns uniform and extremely small particle size,proved to be feasible in synthesizing sulfide solid electrolytes(such as the solid-state synthesis of Li_(6)PS_(5)C_(l)).Spontaneously,this lithium solution can be directly employed in the synthesis of Li_(3)PS_(4) solid electrolytes via liquid-phase synthesis method,in which the centrifugation and heat treatment processes of Li_(2)S are not necessary,providing simplified production process.The as-synthesized Li_(3)PS_(4) exhibits typical Li+conductivity of 1.85×10^(-4) S·cm^(-1) at 30℃.

Solid Phase Synthesis of 4(1H)Quinolones from Resin-Bound Cyclic Malonic Ester

The solid phase synthesis of 4 (1H) quinolones has been reported.

Solid Phase Synthesis of β-Carbolines

Synthesis of β-carbolines on solid phase using TCCA as the key reagent is developed.

Solid Phase Synthesis of 4H-Pyrimido[2,1-b] Benzothiazol-4-ones from Resin-Bound Cyclic Malonic Ester

The solid phase synthesis of 4H-pyrimido[2,1-b] benzothiazol-4-ones has been reported.

SOLID PHASE SYNTHESIS OF ISOXAZOLINES

The solid-phase synthesis of isoxazolines on 2-polystyrylsulfonamidoethanol resin is reported. 2-Polystyrylsulfonamidoethanol resin 1 was reacted with acryloyl chloride to afford 2-polystyrylsulfonylamidoethyl acrylate resin 2, which was further reacted with brominated aldoximes by [3+2] cycloaddition to give isoxazoline resin 4. Resin 4 was treated with aqueous 6 mol/L HCl solution to obtain isoxazolines in good yield and purity.

Structure Based Library Approach to Photosynthesis Inhibitors:The Solid Phase Synthesis of Hydro-Uracils and Thiouracils

A general method for the solid phase synthesis of hydro-uracils and thiouracils is described. Resino ester 2 reacts with various primary amines to give secondary amines 3, which are converted to the resino ureas (thioureas) 4 by treatment with isocyanates (isothiocyanates). Preparation of the hydro-uracils and thiouracils 5 is achieved by acidic cyclization-cleavage from the resin. The synthesis is designed to be amenable for structure based library approach to photosystem II D1 protein inhibitors.

Traceless solid-phase synthesis of 3-substituted isoxazoles from polystyrene-supported vinyl selenide

A novel facile procedure for traceless solid-phase synthesis of 3-substituted isoxazoles in good yields and with excellent purities using polymer-supported vinyl selenide has been developed.

Solid-phase Synthesis of-Haloaldehydes from Polymer-supported 4-(Phenylseleno)morpholine

Polystyrene-supported 4-(phenylseleno)morpholine was synthesized and could be used as an efficient ?selenenylating agent for saturated aldehydes. ?Haloaldehydes were prepared by reaction of polystyrene-supported ?selenoaldehydes with bromine or sulfuryl chloride in good yield and high purity.

Solid-Phase Synthesis of Acrylamide Using Polymer-Supported β-Selenopropionic Acid

A novel polystyrene-supported ?selenopropionic acid has been developed and applied to facile synthesis of acrylamides.

Solid-phase synthesis of (Z)-allyl iodides from 3-acetoxy-2-methylene-alkanoates with recyclable polymer-supported selenium bromide

Reaction of polystyrene-supported lithium selenide with 3-acetoxy-2-methylene-alkanoates afforded the corresponding allyl selenide resins and subsequent cleavage from the polymer by treating with methyl iodide to furnish （Z）-allyl iodides in good yields and high purities. The polymeric selenium reagent can be regenerated and reused. So it is a environmentally benign reagent.

Solid-phase Synthesis of Unsaturated β-Dicarbonyl Compounds from Polymer-supported 4-(Phenylseleno)morpholine

The solid-phase synthesis of unsaturated ?dicarbonyl compounds has been reported.

Pyrolysis of single carbon sources in SBA-15: A recyclable solid phase synthesis to obtain uniform carbon dots with tunable luminescence

Most of carbon dots(CDs) are synthesized in solutions, but the extensive use of solvents produces too much waste, needs complex purification and results in low yield. Particularly for the popular hydrothermal/solvothermal syntheses, safety issues hinder the large-scale production of CDs. Solid phase synthesis in air seems perfect to solve the above problems once for all, but nanoparticle growth in solid phase is always difficult to control. Here we suggest a new method to synthesize CDs in SBA-15 template, just by heating single carbon sources in air. Employing single carbon sources is important, which ensures both homogeneity of the nucleation and uniformity of the nanoparticle growth. The pores confinement of SBA-15 guarantees the uniform sizes of CDs, while the catalytic effect of SBA-15 accelerates the carbonization process of precursors. The products are easily extracted from the template by ethanol, and then the template can be recycled for the next synthesis after calcination. Various CDs are synthesized in this way by using different carbon sources and SBA-15 templates with different pore diameters, respectively. The results show that, the fluorescence properties of these CDs are determined by their composition and surface states, but not the particle sizes. This work opens a new avenue to synthesize uniform CDs in solid phase with high yield, low cost and tunable luminescence.

Solid Phase Synthesis of Ethyl β-Substituted Indolepropionates

A facile solid phase synthesis of ethyl β -substituted indolepropionates is reported. Condensation between indole,polymer-supported cyclic malonic acid ester and aldehyde yielded the trimolecular adducts,which was cleaved by pyridine/EtOH to release the final products in good yield with high purity.

Solid Phase Synthesis of 2-Substituted 1,3-Oxazin-6-ones Using Resin-bound Cyclic Malonic Acid Ester

A facile solid phase synthesis of 2-substituted 1,3-oxazin-6-ones using polymer-supported Meldrums acid has been reported. Reaction of the resin-bound cyclic malonic acid ester with triethyl orthoformate and subsequent dou-ble substitution with amide, afforded the corresponding polymer-supported acylaminomethylene cyclic malonic acid ester, which upon thermal treatment led to 1, 3-oxazin-6-ones in good yields and with high purity.

Aqueous Phase Synthesis and Fluorescence Properties of Inverted Core/Shell ZnSe/CdSe Nanocrystals

We report a facile aqueous phase synthesis for prepar-ing water-soluble inverted core/shell ZnSe/CdSe semiconductor nanocrystals. The samples were characterized by X-ray diffraction (XRD),transmission electron microscopy (TEM),and their optical properties were investigated by using UV-vis-NIR spectropho-tometer and fluorescence spectrophotometer. The results indicate that the synthesized ZnSe/CdSe nanocrystals are inverted core/shell structure with diameter of about 5 nm. Furthermore,their absorption band-edge is red-shifted with the growth of CdSe shell; correspondingly,their emission wavelength can be tuned from 460 nm to 604 nm.

APPLICATION OF THE SULFONATE ESTER GROUP AS A LINKER FOR SOLID PHASE ORGANIC SYNTHESIS

A use of Sulfonate ester as a linker in synthesis of (-aminoalkanols was reported. Diols were tethered onto polystyryl sulfonyl chloride resin, yielding sulfonate resins (2). After cleaved by diethyl amine, diisopropylamine and propylamine respectively, three (-aminoalkanols were obtained.