Zinc chloride catalyzed synthesis of 5-substituted 1H-tetrazoles under solvent free condition

Zinc chloride is an efficient and safe catalyst in the [3 ＋ 2] cycloaddition reaction of organic nitriles with sodium azide in solventless condition. The corresponding 5-substituted ^1H tetrazoles were obtained under mild conditions. This method can overcome disadvantages such as： the use of toxic metals and expensive reagents, drastic reaction conditions, water sensitivity and the presence of dangerous hydrazoic acid.

Zinc Chloride Protects against Streptozotocin-Induced Diabetic Nephropathy in Rats

Diabetes mellitus (DM) is a health problem affecting millions of individuals worldwide. Diabetic nephropathy (DN), as a significant complication of DM, has become the most common cause of endstage renal failure. Oxidative stress constitutes the key and common events in the pathogenesis of DN and antioxidants may play a beneficial role in its prevention. This study was conducted to investigate the effect of Zinc Chloride on streptozotocin-induced diabetic nephropathy in rats compared to Gliclazide, a reference antidiabetic agent. Results showed that Zinc Chloride was able to control STZ-induced DN in rats as it normalized the elevated blood pressure, the increased insulin release, and the decreased blood glucose level. Zinc Chloride also improved kidney function as determined by the restoration of blood urea and creatinine level. Finally, Zinc Chloride was able to boost the antioxidant defenses of the kidney by increasing the reduced glutathione content and decreasing lipid peroxides content in addition to significantly decreasing kidney nitric oxide content compared to diabetic control rats. These results suggest that exposure to Zinc Chloride can protect from diabetic nephropathy and can be used as an adjuvant approach to treatment and prevention of renal damage.

Hydrogen Bond-driven Assembly of Stilbazolium Dye with Zinc Chloride:X-aggregation Induced Photoluminescence and Dual Stimuliresponsive Performance

Combination of D-π-A stilbazolium-type dye DANP(DANP=trans-4-(4″-(N,N-diethylaminostyryl))-N-methyl-pyridinium)with zinc chloride results in a new hybrid(DANP-H)(ZnCl4)(1),and its structure was determined by single-crystal X-ray diffraction method.In the hybrid,two independent DANP-H^2+cations exhibit two kinds of configurations,i.e.,conjugation-broken and conjugation-maintained fashions,and the X-aggregation mode of(DANP-H)^2+cations is driven by strong C–H…Cl hydrogen bonds and C–H…πinteractions.Consequently,blue-shift was observed in its adsorption spectrum,and unquenched red photoluminescence can be monitored.Interestingly,dual stimuli-responsive performance and reversible photo/thermochromic behaviors appeared,which can be assigned to the electron transfer from Cl-3p/DANP-πtoπ*antibonding orbitals of the conjugation-maintained DANP.

Oxidative Desulfurization of Fuel Oil with H_(3)PO_(4)-based Deep Eutectic Solvents

A series of Lewis-acid deep eutectic solvents (DESs) were synthesized by stirring phosphoric acid and zincchloride as raw materials at 80℃ to form H_(3)PO_(4)/nZnCl_(2) (n = 0.1, 0.25, 0.5, 0.75, 1). The DESs were characterized byFourier transform infrared spectrophotometry (FT-IR), thermogravimetry/differential thermogravimetry (TG/DTG), andelectron spray ionization mass spectrometry (ESI-MS). The DESs were used as both extractants and catalysts to removedibenzothiophene from fuels via oxidative desulfurization (ODS). Experiments were performed to investigated the influenceof factors such as composition of DES, temperature, oxidant dosage (molar ratio of O:S), DES dosage (volume ratio ofDES:oil), and number of cycles on desulfurization rate. The results indicated that the removal rate of dibenzothiophene (DBT)was affected by the Lewis acidic DESs, with that of H_(3)PO_(4)/0.25∙ZnCl_(2) reaching 96.4% under optimal conditions (Voil=5 mL,VDES=1 mL, an oxidant dosage of 6, T=50 ℃). After six cycles, the desulfurization rate of H_(3)PO_(4)/0.25∙ZnCl_(2) remained above94.1%. The apparent activation energy of dibenzothiophene (DBT) removal reaction was determined by a pseudo-first orderkinetic equation according to the Arrhenius equation to be 32.34 kJ/mol, as estimated. A reaction mechanism is proposedbased on the experimental data and characterization results.

Zinc-ion hybrid supercapacitors with ultrahigh areal and gravimetric energy densities and long cycling life

Zinc ion hybrid supercapacitor (ZIHSC) with promising energy and power densities is an excellent answer to the ever-growing demand for energy storage devices.The restricted lifespan due to the dendrite formation on metallic zinc (Zn) is one of the main roadblocks.Herein,we investigate the electrochemical capability of oxygen-enriched porous carbon nanofibers (A-CNF) and nitrogen,oxygen-enriched porous carbon nanofibers (N-CNF) cathode materials for structural ZIHSCs.To this end,a series of samples with different chemical compositions (N and O contents) are prepared to present deep insight into the electrochemical mechanism between N/O doping and Zn-ion storage.The as-prepared ZIHSC in the presence of N-CNF cathode and Zn Cl_(2) electrolyte offers a battery-level gravimetric energy density of 143.2 Wh kg^(-1)at a power density of 367.1 W kg^(-1).The free-standing N-CNF electrodes in ZIHSCs enjoy delivering an outstanding areal energy density of 110.4μWh cm^(-2)at 0.24 m W cm^(-2),excellent rate capability,and noticeable cycling stability over 10,000 cycles at 10 A g^(-1)with less than 7%decay.It was also concluded that active pyrrolic N dopants might deliver and facilitate more pseudocapacitance in ZIHSCs than other N configurations,resulting in higher adsorption/desorption and insertion/extraction process of Zn Cl^(+).Taking advantage of the beneficial properties of a free-standing continuous cathode,this novel generation of structural cathode material offers high areal and gravimetric energy densities and mechanical properties in a single zinc-ion-based package.

EXTRACTION OF Zn AND Cd FROM CHLORIDE LIQUORS BY TRI-n-BUTYL PHOSPHATE

Studies have been made on the extraction of Zn and Cd by TBP(tri-n-butyl phosphate) from diluent hydrochloric acid solutions of soldium chloride.The experiments show that the species extracted from diluent HCI solutions of NaCl appear to be predominantly ZnCl_2· 2TBP and CdCl_2·2TBP.For Cd,at lower acidities,anionic complexes of the type H_2CdCl_3 are also extracted.As the acidity is increased,H_2CdCl_4 appear to be predominant complexes in organic phase.For Zn,the acidocomplexes of the type HZnCl_3 appear in organ- ic phase after the acidity of solutions reaching a certain value([HCl]>0.1 mol/L). Furthermore,the ultraviolet absorption spectra of both aqueous and organic phases have been studied,and the infrared spectra of the organic phases have been exomined.The extraction mechanism and temperature effect are also discussed.

Highly efficient synthesis of β-amino esters via Mannich-type reaction under solvent-free conditions using ZnCl_2 catalyst

β-Amino esters were synthesized via ZnCl2-catalyzed Mannich-type reaction of imines and malonate esters under solvent-free conditions in 6 min. The β-amino ester was converted into the corresponding aspartic acid derivatives.

A Facile Approach to Regioselective 1-O-Deacylation of Peracylated Glycopyranoses

The regioselective 1-O-deacylation of peracylated glycopyranoses 1a-d with zinc chloride and zinc oxide in THF/MeOH gave the corresponding tetra-O-acylglycopyranoses 2a-d in good yields.

Preparation of Activated Carbon from Holdfasts of Kelp, Large Brown Seaweed, <i>Saccharina japonica</i>

Dried kelp is one of the most important Japanese foods mainly used as base ingredient. Holdfasts, or rhizoids, of kelp are usually discarded, as rocks, shells, ropes and other contaminants are entangled among them. The purpose of the present study was to examine whether the preparation of activated carbon from holdfasts of Saccharina japonica, a popular kelp harvested in Japan, is possible by a chemical activation technique utilizing zinc chloride, and to study the influence of the process parameters, such as carbonization temperature and the composition of the activator. Under the examined experimental conditions, maximum specific surface area of 1.7 × 103 m2/g, larger than that of a commercial activated carbon, was observed at 600℃ and the zinc chloride composition of 75 mass%.

Thermokinetics of the Formation Reaction of Zinc Histidine Complex

The enthalpy change of reaction of zinc chloride with L-α-histidine in thetemperature range of 25-50 ℃ has been determined by a microcalorimeter. On the basis ofexperimental and calculated results, three thermodynamics parameters (the activation enthalpy, theactivation entropy, the activation free energy), the rate constant and three kinetic parameters (theactivation energy, the pre-exponential constant and the reaction order) of the reaction, and thestandard enthalpy of formation of Zn(His)^(2+) (aq.) are obtained. The results showed that the titlereaction easily took place at the studied temperature.

Reaction of Alkanesulfinyl Chloride with Grignard Reagents： a Convenient Synthesis of Alkyl Sulfoxides

Alkyl sulfoxides were synthesized in good yields from the reaction of alkanesulfinyl chloride with Grignard reagents in the presence of zinc chloride.

Serum zinc level is associated with liver dysfunction caused by white smoke inhalation

Background:White smoke bomb exposure in the military setting could result in organ injuries,which is uncommon and has been rarely described in previous studies.The aim of this study is to observe whether serum zinc levels are associated with liver function after white smoke inhalation.Methods:Fifteen patients with white smoke exposure were the subjects in this study.The clinical manifestations,liver function tests and the serum zinc levels were analysed.Results:The level of serum zinc was increased in the moderate or severe group(n=4)compared with that in the mild group(n=11).The four cases in the moderate or severe group had delayed impairment of liver function with an elevation of alanine transaminase.Additionally,increased blood concentrations of hyaluronic acid were found in three patients in the moderate or severe group.But no hexachloroethane or trichloropropane was detected.Conclusion:This study suggested that serum zinc levels may be associated with the severity of liver injuries after white smoke inhalation.

Zn Cl_2-modified ion exchange resin as an efficient catalyst for the bisphenol-A production

A Zn Cl2-modified ion exchange resin as the catalyst for bisphenol-A synthesis was prepared by the ion exchange method. Scanning electron microscope（SEM）, Fourier transform infrared spectrophotometer（FT-IR）, thermo gravimetric analyzer（TGA） and pyridine adsorbed IR were employed to characterize the catalyst. As a result, the modified catalyst showed high acidity and good thermal stability. Zn2＋coordinated with a sulfonic acid group to form a stable active site, which effectively decreased the deactivation caused by the degradation of sulfonic acid. Thus the prepared catalyst exhibited excellent catalytic activity, selectivity and stability compared to the unmodified counterpart.

Lewis Acid Catalyzed Synthesis of Vinylene Linked Two Dimensional Covalent Organic Frameworks

Comprehensive Summary Vinylene linked covalent organic frameworks(cOFs)have drawn extensive attention due to their desirable stability,carbon conjugation and opto-electronic properties.Suitable catalyst is a key factor in the synthesis of vinylene linked COFs,and proton acids and bases are widely reported as catalysts so far.Herein,we report the synthesis of vinylene linked cOFs using Lewis acid ZnCl2 as catalyst for the first time.Four COFs with hexagonal pores of different sizes are synthesized by the reaction of 2,4,6-trimethyl triazine and a series of aromaticaldehydes.

A facile approach towards self-reinforced antibacterial paper(SRAP)

A facile process to prepare self-reinforced antibacterial paper(SRAP)was developed by in situ synthesis of zinc oxide(ZnO)in partially dissolved cellulose.The SRAP was fabricated by impregnating filter paper in zinc chloride(ZnCl_(2))solution and then reacting with sodium hydroxide(NaOH).Filter paper was firstly impregnated with ZnCl_(2) solution of 65 wt%concentration for 5 seconds at 80℃,and then pressed at 3.85 kPa for 5 seconds to remove excess liquid.Subsequently,the paper was soaked in a 0.8 wt%NaOH solution for 1 hour,and then washed with deionized water,and dried finally to yield SRAP.Energy dispersive X-ray spectroscopy(EDS),X-ray photoelectron spectroscopy(XPS)and scanning electron microscope(SEM)were used to characterize the SRAP.The results revealed that the SRAP contained intact cellulose fibers as the skeleton,gelled cellulose as the matrix,and clusters of nano ZnO particles as the filler.The SRAP had a much higher density,tensile and burst strength,compared with the untreated cellulose paper,and the folding strength was enhanced by more than fifteen times.In addition,the SRAP had outstanding antibacterial properties due to the presence of nano ZnO particles.