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(1) It was observed in the reaction of organic chloride with silver nitrate that the irregular catalytic action can be avoided by carrying experiments in a dark room. (2) Silver nitrate was interacted with several organic chlorides which were highly reactive in SN2 type reaction and the kinetic data obtained were fully discussed. (3) Some organic polychlorides were reacted with silver nitrate and with potassium iodide and rates obtained in these reactions were discussed.

An unequivocal synthesis of the title compound was achieved by means of intramolecular cyclization of 6-amino-6-deoxy-1,2- O -isopropylidene-3- O -toluene- p -sulphonyl-α- D -allofuranose (7) and N -acetylation of the resulting epimino derivative. The derived methanesulphonate 9 readily underwent a displacement reaction with sodium benzoate in N,N -dimethylformamide to give 3,6-acetylepimino-5- O -benzoyl-3,6-dideoxy-1,2- O -isopropylidene-β- L -idofuranose (10) , whose structure was correlated with that of a product previously obtained from the solvolysis of 3-acetamido-3-deoxy-1,2- O -isopropylidene-5,6-di- O -methanesulphonyl-α- D -glucofuranose (1) .

The quaternization of poly(ar-vinylbenzyl chloride) with trimethylamine is shown to be a nucleophilic displacement reaction, the kinetics of which are complicated by several factors, notably differences in the reactivities of o- and p-chloromethyl groups (position isomerism), differences in the reactivities of groups as a function of the reacted or unreacted status of immediately adjacent groups (neighboring group effect), and differences in the reactivities of groups arising from the microtacticity of the polymer segment (configurational effects). Estimates of mean rate constants, activation energies, and preexponential factors are given for high purity poly-p-vinylbenzyl chloride and for the analogous ortho polymer.

Data on the kinetic anion replacement systems calcite-PO 4 (super -3) , calcite-F (super -) , gypsum-CO 3 (super -2) , and gypsum-PO 4 (super -3) are given, along with concomitant Sr (super +2) inclusion into the final product. In a system containing several anions, only the anion forming the least soluble compound with the available cation is stable. The replacement reaction rate is directly proportional to the solubility difference between the original solid and final product. Several other variables also affect the reaction rate including temperature, column flow rate, influent pH, surface area of the initial solid, concentration of extraneous ions, and concentration of active anion. These variables affect diffusion rates to and from reaction sites as well as differences in solubility between initial and final reaction products. The crystal structure of the resulting product greatly affects the concomitant removal rate of Sr (super +2) into the resulting product.

Rates of displacement of primary tosyloxy groups of acetylated carbohydrate derivatives with iodide ion have been measured. The products of the reaction have been isolated in all instances. The displacement reaction is second order and the differences in rate coefficients are discussed by the geometry of transition state.

A detailed study of the kinetics of the reaction betweena brompropionate and silver ions has been made in very dilute solutions at 27°C.

Infrared and nuclear magnetic resonance spectra of palladium (II) monothio-β-diketonates were studied in comparison with those of palladium (II)β-diketonates. The following novel reactions have been found. Namely, palladium dithioacetylacetonate was obtained in the reaction of monothioacetylacetone and palladium ion in acid solution by the reaction which may be called as “ligand atom replacement reaction” and palladium monothio-β-diketonates were obtained from disulfides of monothio-β-diketones and palladium ion. The reason for the occurance of this reaction may be reasonably explained by the high affinity between palladium and sulfur and the high stability of the palladium chelates formed.

Thioloxy germanes of the type Ge(SR)4(R = C2H5, C3H7n, C3H7iso, C4H9n, C4H7iso, C12H25n, C6H5CH2 and C6H5) have been synthesized by the ammonia method in good yields. Germanium tetra-isopropoxide has been found to interchange its isopropoxy groups with thiols in the presence of a catalyst. Reactions of Ge(SPrn)4 with ethanol (anhydrous) and of Ge(SBun)4 with water have been studied. A higher homologue Ge(SCH2C6H5)4 has also been obtained by a displacement reaction of Ge(SPrn)4 with toluene α-thiol.

Reactions of alkyl halides with potassium cyanate have been carried out in several aprotic solvents. Dimethylformamide and dimethyl sulfoxide have been proved to play a superior role as aprotic solvents in the displacement reaction and also in the subsequent trimerization of the isocyanates. Several trialkyl isocyanurates have been obtained in yields better than those of the other known methods. From 2-alkoxyethyl halides and 2-vinyloxyethyl chloride respectively, tris-(2-alkoxyethyl) isocyanurates and tris-(2-vinyloxyethyl) isocyanurate have been synthesized. The presence of water in the reaction mixture results in the formation of 1,3-dialkyl ureas, consequently decreasing the yield of isocyanurates.

We have synthesized (±)-loliolide (7 a), (±)-actinidiolide (11 a), (±)-dihydroactinidiolide (16), and (±)-isodihydroactinidiolide (18) through various reaction paths starting from homosafranic acid (4 a). Thus, (±)-actinidiolide has been synthesized for the first time, and this result allows to discard the alternative formula 11 b for that compound [2]. By investigation of the sensitized photooxygenation of methyl homosafranate (4 b), this reaction is shown to lead to an interesting spiro-peroxylactone 25, beside the expected endo-peroxide 23. Specific oxygenation of the tetrasubstituted double bond of methyl homosafranate, and cyclisation of the hydroperoxide 24 thus produced, are believed to account for the formation of such a particular compound. The base-catalysed rearrangement of the endo-peroxide 23 gives rise to two compounds, one being the expected keto-hydroxy-ester 26. The other - to which is assigned the glycidic ester structure 27 - obviously results from an internal displacement reaction on oxygen in 23. It is note-worthy that the sensitized photooxygenation of methyl homosafranate proceeds directly to the same glycidic ester when it is carried out in an alcaline solution.

With the reaction between N 4 S 4 and PCl 3 a new compound was prepared of the composition P 2 NCl 7 . With X-Ray analysis the compound was found to be identical with the product of a reaction between ( PNCl 2 ) 3 and PCl 5 . A structure containing PNCl 3 − and PCl 4 + ion is suggested.

Electron donors (D) and acceptors (A) are classified into types based on their structure before interaction. Interactions were either dissociate (chemical displacement reaction) or associative (molecular-complex or -compound formation). Pair types included molecular complexes (D-A), molecular compounds (D yields A), and bimolecular displacement reactions (A+D yields B+C). Probable charge-transfer spectra are tabulated for several molecular complexes.

Omega Chrome Fast Blue 2G was used as an indicator for the direct titration of calcium, magnesium, manganese and nickel. A displacement reaction was described for the titration of lead and cadmium. Fenugreek mucilage which is a colourless polysaccharide was used as medium for spot tests. The method is illustrated by spot tests for Ca, Mg, Mn, Ni, and Co. It has the advantage of sensitivity and simplicity.

In the displacement reaction with sodium iodide in acetic anhydride solution the rates of reaction of four isohexide tosyl esters were compared to that of an O-acetyl-O-tosylisosorbide recently described. The tosyloxy group in the latter compound was replaced rapidly and was therefore in the 5-endo-position, the compound being correctly named 2-O-acetyl-5-O-p-toluenesulphonyl-1,4;3,6-dianhydro-D-glucitol. The product of the reaction was isolated as a crystalline material, and was identified as 2-O-acetyl-5-deoxy-5-iodo-1,4;3,6-dianhydro-L-iditol.

The preparation of several Mannich bases of N -methyl-2-phenylsuccinimide was accomplished under a variety of conditions. There is no report in the literature of the application of the Mannich reaction to N -substituted-2-arylimides. The next higher homologs of these Mannich bases were prepared by a base displacement reaction in toluene between the lithium salt of N -methyl-2-phenylsuccinimide and the appropriate β-chloroethylamine hydrochlorides. Preliminary pharmacological data are reported.

The nature of IIa Oxides, particularly MgO, CaO and BaO, in cryolite melts was studied by means of the freezing point depression of cryolite. In the binary system of these melts, the displacement reaction accompanied and the formation of fluorides and aluminate were observed by the X-ray diffraction analysis.As the mechanism of the reaction, it is the most probable that the formation of complex ions of Al2O3- and MgF3- occures in the system of cryorite-MgO, while the formation of AlO2- and the dilution of Na+ by Ca2+ or Ba2+ are almost identical in the system of cryolite -CaO, and -BaO.

The displacement or replacement of adsorbed nitrogen from the surface of an evaporated barium film has been demonstrated by a series of flow experiments using a glass uhv system. The method consists of passing small controlled oxygen fluxes over a film that has previously sorbed nitrogen. The oxygen displaces nitrogen which is continually pumped away to be measured. The results show that for nitrogen sorptions by a barium film of less than 0.03 cm3 Torr/cm2 of actual film area, only a small fraction of the oxygen pumped (

In this work, formation of iron oxide nanoparticles by mechanochemical reactions in different milling times was studied. During the mechanical milling, the solid-state displacement reaction of 3Na2CO3 + 2FeCl3.6H2O = 6NaCl + Fe2O3.6H2O + 3CO2 was induced to form iron oxide nanoparticles. A simple washing process was done to remove NaCl by-product and subsequently the particles dried at 105°C for 12h. Nanoparticles size and the mechanochemical effect were characterized by X-ray diffraction (XRD) and particle size analysis. Experimental results show that increasing the milling time can effectively reduce the nanoparticle size of Fe2O3. The average Fe2O3 nanoparticles size is about 14nm for 2h and 4nm for 5h milling process.

A piezoelectric crystal detector utilizing a mercury displacement reaction is described for the detection and determination of sulfur dioxide. The mercury vapor produced by bubbling the sulfur dioxide through a mercurous nitrate solution is detected by a gold-coated piezoelectric crystal due to the formation of a mercury amalgam. This detector exhibits good sensitivity and selectivity and can be used in the ppb and ppm concentration ranges of sulfur dioxide.

Carbonyl sulfide (COS) was prepared by a replacement reaction from potassium thiocyanate (KSCN) in 50% sulfuric acid. 14C-COS or 35S-COS can be prepared by the same method, depending on the position of the label in the starting KSCN. The yield of the final product is in excess of 60%, and radiochemical purity was 99.5%.

On amination of 2-X-4-phenylpyrimidine (X=F, Cl, 1) with potassium amide in liquid ammonia at −75°. 2-amino-4-phenylpyrimidine is obtained as main product, together with some 3-amino-3-phenylacrylonitrile. It was proved using 2-halogeno-4-phenyl-[1,3-15N]-pyrimidines that the displacement reaction occurs for the greater part via an SN(ANRORC)-mechanism (82% for X=F, 88% for X=Cl and 73% for X=1). It was further found that the 3-amino-3-phenylacrylonitrile, obtained from the 15N-labelled pyrimidines. does not contain15N. This very unexpected result is discussed.

A nucleophilic displacement reaction of methyl 3, 4-O-isopropylidene-2-O-(trifluoromethanesulfonyl)-6-O-trityl-β-D-talopyranoside (10) with tetraalkylammonium fluorides in acetonitrile gave methyl 2-deoxy-2-fluoro-3, 4-O-isopropylidene-6-O-trityl-β-D-galactopyranoside (11). Excellent conversion of 11 into 2-deoxy-2-fluoro-D-galactose (1) was achieved by hydrolysis with 5 N hydrochloric acid.

HCl(g) exhibits a chemisorptive replacement reaction at a Pb(110)O surface to form an ionic adlayer PbIICl2; this adpayer is removed on exposure to HCl(g), the reaction exhibiting a critical temperature dependence. The latter is attributed to formation of a volatile lead hydrogen dichloride above 289 K.

The displacement reaction between sodium thiophene-3-thiolate and methyl 3-(bromomethyl)thiophene-2-carboxylate (5) gave the expected thioether 7a. Basic hydrolysis afforded the carboxylic acid 7b; conversion to the acid chloride, and treatment of the latter with stannic chloride then produced the bisthienothiepinone 1. Using analogous reactions the isomers 2-4 were also synthesized.

The title anation reaction was studied at 73.4°C in the presence of added nitrate ion. The nitrate ion accelerated the reaction by an amount which was dependent on the pH of the solution. This is interpreted in terms of the effect of nitrate ion on ion-pair formation.

The isomerization of methyl isocyanide in the presence of methyl radicals takes place by two mechanisms. One is the simple free-radical displacement reaction which has been described previously. The other is through a direct transfer of energy from vibrationally excited ethane molecules. The vibrationally sensitized component can be quenched by increasing the total pressure.

The reaction of diphenyl sulfone with elemental sulfur to give diphenyl sulfide and sulfur dioxide at above 300°C was investigated using diphenyl sulfone-1-14C. By the degradation of the product, diphenyl sulfide-x-14C, it was found that no migration of sulfide group took place. β-Naphthyl phenyl sulfone was also subjected to the same reaction, and not only β-naphthyl phenyl sulfide but also di-β-naphthyl sulfide and diphenyl sulfide were found among the products. These observations appear to indicate the reaction to be a rather simple displacement reaction that involves the initial attack of polymeric sulfur radical chain at C-1 bearing sulfonyl function.

A study of the isotope exchange of the ethyl esters of α-brommercuryarylacetic acids with203Hg Br2 and 70% aqueous dioxane at 60°, made it possible to arrange the substituents in the following series in order of decreasing reaction rate: p-I, Br, Cl > p-F >H > o-CH3 > p-CH3> p-typet. C4H9.

Rates of displacement of Ni(II) in bis(dithiocarbamato)Ni(II) by Cu(II) with a variety of substituted dithiocarbamic acids in different solvents have been determined and a mechanism of the reaction and potential application of the displacement reaction to spectrophotometric titration of Cu(II) for its quantitative determination are suggested.

(1) Chlorination of DL-N-benzoylallothreonine ethyl ester with thionyl chlodide in benzene in the presence of pyridine gave the lower-melting isomer of ethyl-DL-α-benzamido-β-chlorobutyrate, m. p. 84.5-86.5°, in a yield of 57%. On the other hand, chlorination with phosphorus pentachloride in chloroform gave the higher-melting isomer, m. p. 99-100°. (2) Two isomers of α-benzamido-β-benzylmercaptobutyric acid (derivatives of thiothreonine A and B) were synthesised. The chlorine atom of ethyl DL-α-benzamido-β-chlorobutyrate could be replaced by a sulfhydryl group by the action of benzyl mercaptan. A remarkable effect of different solvents on this replacement reaction was described.

Conductivity data have been combined with transport fractions to show that silver chloride in dilute solutions in silver nitrate can be regarded as being almost completely in the form of complex cation. The mobility of the complex ion is shown to be about one-half that of silver ion.

Isopropylidenation of 1,2-O-cyclohexylidene-myo-inositol and its 3-O-tosyl- and 3-O-benzoyl derivatives with 2,2-dimethoxypropane in N,N-dimethylformamide in the presence of acid catalyst gave the corresponding 4,5- and 5,6-O-isopropylidene derivatives. Selective benzoylation of 1,2-O-cyclohexylidene-4,5-O-isopropylidene-myo-inositol with benzoyl chloride in pyridine gave mainly the 3-O-benzoate, whereas with benzoic anhydride the 6-O-benzoate. Several unaccessible blocked inositols were prepared by displacement reaction of the protected sulfonyl derivatives with sodium benzoate.

The results of polarization measurements for the reduction of mercury (I) and mercury (II) on a rotating platinum electrode, and the oxidation of silver and amalgamated silver at a rotating silver electrode are presented. For mercury (I) and mercury (II) diffusion coefficients were estimated from limiting current measurements as a function of rotation speed and temperature. The Values obtained for the diffusion coefficients at 25°C, and activation energies were: The kinetics of the reactions between a rotating silver disc and solutions of mercury (I) and mercury (II) are also reported. The mercury (I) reaction is a displacement in which mercury is deposited and silver goes into solution. The kinetics are first order-first order reversible, and can be quantitatively accounted for by assuming that the diffusion of mercury (I) to the surface and silver (I) away from the surface are jointly rate controlling. At temperatures below 35°C, the mercury (II) reaction is a dissolution, controlled by the speed at which mercury (II) ions diffuse to the reacting surface. Above 35°C, the mercury (II)-silver reaction is a displacement, with somewhat irreproducible kinetics. The changeover between the two reactions at 35°C apparently occurs because the displacement reaction is thermodynamically favoured above 35°C.

In a dinitrogen complex, if the M-N2 bond is stabilized by a convenient electron releasing co-ligand (X) in trans position, a displacement reaction may occur with retention of N2. Hence, the replacement of a tertiary phosphine, bound to a trans-{XRe (N2)} metal site (X = Cl or S2PPh2), by an isocyanide may occur in preference to N2 loss, leading to mixed dinitrogen-isocyanide species (e.g. equation 1, L = PMe2Ph) (Pombeiro 1982), where the strong organic π-acceptor ligand coexists with N2.