KINETIC AND APPLICATION: STUDIES ON THE REACTION SYSTEM OF OSMIUM(Ⅳ)-ARSENIC(Ⅲ)-CHLORATE

The experiments have proved that Os(Ⅳ) has very strong catalytic effect on the chlorate oxidation of As(Ⅲ) in perchloric acid media, and As(Ⅲ) exhibits a sensitive single-sweep oscillopolarographic wave at-0.75 V vs. SCE. The kinetics of this catalytic reaction has been investigated by the initial rate procedure. The mechanism has been proposed. A new and highly sensitive catalytic reaction-oscillopolarographic method for the determination of ultratrace amounts of osmium has been described, based on the Os(Ⅳ) catalytic effect on the reaction. The linear range of 5.0×10^(-11)-4.4×10^(-9) mol/L and 6.0×10^(-9)-1.3×10^(-7) mol/L Os was obtained using the fixed-time procedure and the initial rate procedure, respectively. Osmium in refined ore was analysed by this method.

NEW HETEROCYCLIC SYSTEM SYNTHESIS H THE REACTION OF 2,3-DIHYDRO-1,5-BENZOTHIAZEPINES WITH DICHLOROCARBENE

The reaction of two series of 2,3-dihydro-1,5-henzothiazepines Ⅰ with dichloro- carbene,gave azirino[2,1-d][1,5]benzothiazepines Ⅷ,azirino[2,1-e][1,6]benzothiazocines Ⅸ, pyrrolo[2,1-b][1,3]benzothiazoles Ⅹ,substituted-cyclopropanes Ⅺ and 2H-1,4-benzothiazin-2-ones Ⅻ.The structures of these products were confirmed by the analytical and spectral data.Compound Ⅷ and Ⅸ are two new ring systems.

RESEARCH ON THE WATER-RESISTANCE OF MAGNESIUM OXYCHLORIDE CEMENT——I:THE STABILITY OF THE REACTION PRODUCTS OF MAGNESIUM OXYCHLORIDE CEMENT IN WATER

In this paper .the change of the crystalline phases in hardened magnesium oxychloride cement (MOC) paste in mater was analyzed by XRD. It was developed that the reaction products 5 phase or 3 phase of MOC are instable in water and can be changed into Mg(OH)2 by the action of water, which causes the content of 5 phase or 3 phase to be less and less,the content of Mg(OH)2 to be more and more and the strength to be the lower the lower,after hardended MOC paste was immersed in water. The change of 5 pliase and 3 phase into Mg(OH)2 is not a dissolve process, but a hydrolysis process. The hydrolysis products of 5 phase and 3 phase are Mg(OH)2 precipitation and soluble Cl-,AIg+ ions and H2O. The hydrolysis is sponta-neous thermodynamically and its chemical kinatic equation is C = C,,e-k Thus .it is suggested that only by enhancing the stability of 5 phase or 3 phase in water and preventing 5 phase or 3 phase from the hydrolyzing can the water resistance of MOC be improved well.

THE REACTION OF BENZOYL SUBSTITUTED HETEROCYCLIC KETENE AMINALS WITH ARYL AZIDES.A FACILE APPROACH TO SYNTHSIZE 1,5-DIARYL-4-(2-IMIDAZOLINYL)-1,2,3-TRIAZOLES

Heterocyclic ketene aminals 1 react with aryl azides 2 to give the titled compounds 3,and in some cases also with the formation of fused heterocycles 4.

The Reaction of Sodium Perfluoroalkanesulfinate with PCl_3

The reaction between sodium perfluoroalkanesulfinate(1)(Rf=a,Cl(CF_2)_4;b, Cl(CF_2)_6;c,Cl(CF_2)_8;d,n-C_6F_(13);e,n-C_8F_(17);f,H(CF_2)_4OCF_2CF_2)and phosphorus trichloride in acetonitrile at 0℃ resulted in the formation of an unstable intermediate,which was hydrolysed directly with aqueous sodium hydro- xide solution to give the corresponding perfluorocarboxylic acid in good yield.

AB INITIO STUDY ON THE REACTION OF CH WITH NH3

The mechanism of the reaction of the CH radical with NH3 has been theoretically studied at the MP2/6-31G** level. The calculation results Indicate that the insertion reaction path Is the favourable channel, which is in line with Lin's proposal based on their kinetic experiments. A detailed description of the complicated insertion reaction path is presented.

THE REACTION OF AROMATIC ALDEHYDES WITH p-NITROBENZYLLIBUTYLTELLURONIUM BROMIDE BY PHASE TRANSFER CATALYSIS

Under the condition of solid-liquid phase transfer catalysis, olefins were obtained by the reaction of p-nitrobenzyldibutyltelluronium bromide with aromatic aldehyde.Under the condition of liquid-liquid phase transfer catalysis,however,different products were obtained due to the reactivity of different bases or aldehydes.

Studies on the Reaction of Vinyl Triazole Derivatives with Hydroxylamine

In this paper the reaction of vinyl triazole derivatives with hydroxylamine hydrochloride under the action of sodium carbonate was studied. The result indicated that cyclization took place and new heterocyclic compounds of 1,2-oxazocyclopentanes were obtained.

THE STUDY OF THE REACTION OF THE QUASI-AROMATIC COMPLEX [Ni(PnAO)-6H]^(?)WITH FORMALDEHYDE: KINETICS AND MECHANISM

The kinetics of the reaction of [Ni(PnAO)—6H]° with formaldehyde was studied in H_2O—CH_3OH solution under neutral condition and a complicated mechanism with three steps including competitive, consecutive and reverse reactions was proposed.

STUDY ON 1,2,3-DIAZAPHOSFHOLE V THE REACTION OF 1,2,3-DIAZAPHOSPHOLE WITH 2-BUTYNE-1,4-DIOL

2-Acetyl-5-methyl-2H-1,2,3—diaraphosphole 1 reacted with 2—butyne—1, 4—diol to form a tricoordinated phosphorus compound 7, which then rearranged to a novel 2, 3-disubstituted-1, 3-diene.Similar rearrangement has been observed when diphenylchloropbosphine reacted with 2-butyne—1,4-diol

THE REACTION OF PYROYUNACONITINE WITH NBS—1% HCl

Treatment of pyroyunaconitine 1 with NBS—1% HCI soln.at room temperature for 12 h.leads to compound 2 having an α,β—unsaturated ketone system in 15% yield.It is easi- ly converted to 3 via an acyloin rearrangement during purification.Structures of 2 and 3 were elucidated by spectral methods.

The Reaction of ∝, β-epoxyketones with methoxymethylenetriphenylphosphorane, A New Approach to ∝-alkylsubstituted-γ-hydroxy-d, β-unsaturated aldehydes

The reaction of α, β-epoxyketones with methoxymethylenetriphenyl- phosphorane provides a method for the preparation of α-alkylsubstituted γ-hydroxy-α, β-unsaturated aldehydes with one carbon homologation and retention of configuration.

PERFLUOROALKANESULFONYL IODIDE GENERATED FROM THE REACTION OF PERFLUOROALKANESULFINATE SALT WITH IC1

The reaction between perfluoroalkanesulfinate salts(1)[R_fSO_2M R_f=a,Cl(CF_2)_4;b,Cl(CF_2)_6;c,Cl(CF_2)8;d,n-C_6F_(13);e,n-C_8F_(17);M-Na;K; Hg(I)]and iodine monochloride in dichloromethane at low temperature(e.g. -30--50℃)resulted in the formation of the corresponding perfluoroalkane- sulfonyl iodides(2),which were identified by their 19_F NMR spectra.The perfluoroalkanesulfonyl iodides generated in situ reacted smoothly with olefins to forum 1:1 adducts with good yields.Thus,these reactions provide another method for the synthesis of the very unstable perfluoroalkanesulfonyl iodide.

STUDIES ON POLYHALOALKANES Ⅳ. THE REACTION OF POLYFLUOROALKYL IODIDES WITH SILVER(I) SALTS

The conversion of polyfluoroalkyl iodides into the corresponding carboxylic acids by the reaction with silver (I) salts is described.

THE REACTION OF SUBSTITUTED PHENOXY ACETYL CHLORIDE WITH TRIMETHYL PHOSPHITE

Substituted phenoxy acetyl chloride reacted with trimethyl phosphite to form an unexpected substituted phenoxy acetic acid ester, confirmed by;HNMR, IR and MS. The mechanism suggested is different from that of Arbuzov reaction.

Study on the Reaction of α-Thiobenzoylthioformylmorpholine

The reactions of α - thiobenzoylthioformylmorpholine and compounds bearing amino group, such as diamine, aminoguanidine, semicarbazide and phenylacetylene have been explored.

Studies on the Reaction Mechanism of CO_2-Reforming of Methane over Co/γ-Al_2O_3 Catalyst

TPPR and XPS characterizations were combined to study the reaction mechanism of CO2reforming of methane to syngas over Co/γ-Al2O3 catalysts. CH4 shows a tendency to form surface carbons by deep dissociation at high temperatures. CO2 dissociation reaction also occurs at >673K. It is believed that carbide carbons are active species to generate CO by rcacting with o atoms dissociated from CO2. In the reaction,Co(0) particles are responsible for dissociating CH4 to form active C. abstracting an O atom from CO2 molecule, and transferring O atom to C to form CO.

A THEORETICAL STUDY OF THE THERMODYNAMIC AND KINETIC PROPERTIES FOR THE REACTION OF FORMYL CYANIDE DECOMPOSITION

We compute the thermodynamic and the kinetic properties for the reaction: HCOCN→HCH+CO using the statistical theory and the transition-state theory.The equi- librium constants and the rate coefficients of this reaction are also reported here,and the half lives of formyl cyanide at different temperatures are first estimated in this work.

A SIMPLE ACCESS TO UNSOLVATED MONOMERIC COMPLEXES OF EARLY LANTHANIDE IODIDES(CH_3OCH_2CH_2C_5H_4)_2LnI(Ln=La,Nd)VIA THE REACTION OF[(CH_3OCH_2CH_2C_5H_4)_2LnCl]_2 WITH NaI AND X-RAY CRYSTAL STRUCTURE OF THE LANTHANUM COMPLEX

(CH_3OCH_2CH_2C_5H_4)_2LnI(Ln=La,Nd)complexes have been synthesized by the reaction between NaI and[(CH_3OCH_2CH_2C_5H_4)_2LnCl]2 in THF;A single crystal X-ray study has shown that the lanthanum complex is an unsolvated monomer with lanthanum(Ⅲ)in a trigonal bipyramidal coordination geometry if the cyclopentadienyl ring is regarded as occupying a single polyhedral vertex.

STUDIES ON THE REACTION OF SULFUR,SELENIUM AND TELLURIUM WITH SODIUM HYDROXIDE UNDER PHASE TRANSFER CATALYSIS(Ⅱ).A CONVENIENT METHOD FOR THE SYNTHESIS OF BI(ACYL)DISULFIDES

A simple and general method for the synthesis of bi(acyl)disulfides is reported.Sulfur is allowed to react with sodium hydroxide to give sodium disulfide at 65℃ under PTC,which can react with acyl halides to afford bi(acyl)disulfides in good to excellent isolated yields.The effects of solvents and phase transfer catalysts are discussed.