Study on the adsorption of uranium, dissolved in sea water, on hydrous titanium(iv) oxide was carried out and the mechanism of this adsorption was discussed. Hydrous titanium (iv) oxide was prepared by the precipitation method from titanium (IV) chloride and aqueous ammonia at different temperatures. The amount of OH group on the surface of hydrous titanium On oxide crystallites, which was measured by adsorption of fluoride ion, decreased with increasing preparation temperature (Fig.3). Potassium adsorbed increased linearly with increasing the amount of surface OH group of hydrous titanium ( IV) oxide. On the other hand, the reverse relation existed between the amount of uranium adsorbed and that of surface OH group (Fig. 7). The enthalpy change (4H) was found to be -3.4 kcal/mol and 11.1 kcal/mol for the potassium adsorption and the uranium adsorption on hydrous titanium (iv) oxide, respectively. These results suggest that the uranium adsorption is accompanied by certain complex reactions.

View full abstract

The reduction characteristics of supported nickel oxide catalysts prepared by impregnation, co-precipitation and gel-mixing have been investigated by a temperature programmed reduc- tion method. The reduction curves were markedly affected by the method of preparation of the catalysts, the amount of metal oxide loaded and the kinds of supports. Alumina, silica, silica-alumina and magnesia were used as the supports. The impregnated catalysts had a temperature of principal peak in reduction rate similar to that for nickel oxide. This result shows that nickel component is supported in the state of free nickel oxide. The reduction peaks of the catalysts co-precipitated and gel-mixed shifted to higher temperatures. This phenomenon suggests that interaction acts between nickel oxide and the supports. From these observation, it was concluded that the impregnated catalyst was more easily reduced than the catalysts prepared by co-precipitation and gel-mixing.

View full abstract

The reduction characteristics of co-precipitation nickel oxide catalysts were investigated by a temperature programmed reduction method. The reduction were characterized by the amount of nickel oxide loaded and the kinds of supports. Alumina, silica and magnesia were used as the supports. The reduction rate vs. temperature curve of a NiO/SiO₂ catalyst showed a large and broad reduction peak, and the curves of NiO/Al₂0₃ and NiO/MgO showed two peaks splitted. The nickel component on an Al₂0₃ exhibited a characteristic reduction peak at 400°C. The nickel component on a MgO support showed a similar characteristic peak at 300°C. From the redution curves of the catalysts precipitated at different values of pH, it was concluded that the catalysts co-precipitated consist of a mixture of the support and different amount of nickel loaded. The catalytic activity was tested with the hydrogenolysis of propane. The morphology of catalysts supported on silica was observed before and after hydrogen reduction with a scanning electron microscope. The morphology of the catalysts remained unchanged during the reduction. The amount of carbon monoxide chemisorbed increased with increasing amount of nickel loaded.

View full abstract

Alkylation of phenol with isobutylene was carried out over various catalysts by using a continuous flow reactor under an atmospheric pressure at 182-250°C. Although solid acids such as Si0₂Al₂0₃ and Al₂0₃ were found to be active catalysts (Table 1), the catalytic behavior of BrOnsted acid (SiO₂Al₂0₃) differed from that of Lewis acid (Al₂0₃). SiO₂Al₂0₃ effectively promoted the alkylation at a lower temperature, and p-t-butylphenol (p-TBP) was preferentialy more formed than o-t-butylphenol (o-TBP) in the whole range of a reaction temperature (Fig.1). The isomerization of o-TBP to p-TBP, catalyzed by Si0₂Al₂0₃, occurred at a low temperature (Fig.4). On the other hand, the alkylation was effectively promoted by Al₂0₃ at a temperature as high as 220°C (Fig.2). The isomerization of o-TBP catalyzed by Al₂0₃ (Fig.4) did not occur. The IR spectra of phenol, isobutylene, o-TBP adsorbed on Al₂0₃, and fluorinated Al₂0₃ were recorded to elucidate the difference between catalytic behavior of Lewis acid and that of Bronsted acid (Fig.6-10).

View full abstract

Dehydrogenation of ethylbenzene over various poly (metal phthalocyanine) catalysts(Poly-M-Pc) was studied by a continuous flow system at the atmospheric pressure. The percentage of the yield of styrene depended on the central metals. The catalytic activity was found to decrease in the order, Cr Ni Co Fe=Cu, whereas the selectivity of the catalysts to styrene was almost the same irrespective of the central metals. The mixed type catalyst of Poly-CrNi-Pc was more active in the yield of styrene of the single type catalyst of Poly-Cr-Pc. So introduction of two kinds of metal ions to the enlarged cojugated system of the catalyst gave special effect on the yield of styrene. In the oxidative dehydrogenation of ethylbenzene, PolyFe-PC catalyst was most active, but Poly-Cr-Pc catalyst, which was most active in the dehydrogenation of ethylbenzene, gave little yield of styrene. Poly-Cr-Pc catalyst showed higher conversion and selectivity than Cr₂O₃.

View full abstract

The property of directly fluorinated active carbon or carbon black at room temperature is different from that of the common graphite fluoride which is prepared at high temperature. The yield of graphite fluoride for the fluorination reaction of active carbon at 300°C is very low compared with that for the fluorination reaction of coke or graphite.
The effects of microstructure and surface functional groups of active carbon on the rate of fluorination were studied by means of BET, thermogravity and ESCA. The oxidation of halogen ions by the fluorinated active carbon at room temperature were investigated by determining oxidized halogen ion by the electrode for sensing fluoride ion and by the iodometry. The functional groups of the residue compounds were identified by IR spectra. The white graphite fluoride obtained at the temperature of 270 to 300°C was analysed by DTA.
The direct fluorination rate of active carbon at room temperature depends on both the specific surface area and surface functional groups. The fluorinated active carbon oxidized not only iodide ion but also bromide and chloride ions at room temperature, and the oxidizing power is kept for two months at least. The yield of white graphite fluoride for the fluorination reaction of active carbon at 270°C became high through the pretreatment of the material with fluorine gas at room temperature.

View full abstract

At first, indium, zinc, cobalt, manganese and nickel were picked up as suitable elements based on G⁰-T diagram of the reactions. Then, each fundamental reaction was checked experimentally. In the case of cobalt, manganese and nickel, reaction ( 1 ) hardly proceeded below 900°C under atmospheric pressure of Br2. Therefore, detailed experiments were carried out on zinc and indium.
In the case of zinc, the equilibrium conversion of Br, for reaction ( 1 ) was estimated to be 37% at 900°C and that of ZnBr₂( g ) for reaction ( 2 ) was estimated to be 5% at the same temperature. Also in the case of indium, both the equilibrium conversions of Br₂ and of InBr₂( g ) turned out 10% under the same conditions.
As the rate of conversion was rather low, large amounts of unreacted substances should be recycled to proceed these reactions. In the hydrolysis of both ZnBr₂ and InBr₂, the use of five and ten times larger amount of H₂0 could reduce the amounts of unreacted metal bromides to about a half and one third of the values mentioned above, respectively. Under the present conditions the two-step sub-cycle using the metal oxide is considered to be difficult to realize from technical points of view.

View full abstract

Dimercaptomaleonitrile (H₂mnt or H₂L) reacts with transition metal ions to form water soluble complexes, AuL₂^-, ZnL₂^2-, CdL₂^2-, PdL₂^2-and CoL₃^2-, which can be quanti- tatively extracted into chloroform as the ion-pair, Q_n[ML_m], with tetrahexylammonium cation (Q⁺). Extraction constants of the ion-pair, K_ox(=[Q_nML_m]₍₀₎[ML_m^n-]^-1[Q⁺]^-n), were determined by the measurement of the ion exchange equilibria;
The values of log K_ox were 22.41 for ZnL₂^2-, 22.40 for CdL₂^2- and 30.28 for CoL₃^3- at I=0.3(Na⁺+(SO₄^2-, Cl0₄^-, OAc^-)), and 22.85 for HgL₂^2-, 23.31 for NiL₂^2- and 23.50 for PdL₂^2- at I=0.5(Na⁺+(SO₄^2-, Cl0₄^-, OAc^-)), respectively.
For mnt complexes of the same geometry and of the same charge-type, the extractability increase with ionic radius (tetrahedral ions ZnL₂^2- CdL₂^2- HgL₃^2-; square-planer ions NiL₃^2- PdL₂^2-). The square-planer ions are more readily extracted than the comparable tetrahedral ions (ZnL₂^2- NiL₂^2-, CdL₂^2- PdL₂^2-). The relative extraction constant, K, for the reaction,
has decreased by increasing in anionic charge of the complexes (AuL₂^- M(ii)L₂^2- CoL₃^2-).These values of the extraction constants were also compared with those of the some other metal complexes and it was concluded that mnt has a desirable properties as a reagent for the ion-pair extraction of transition metal ions.

View full abstract

We have previously reported the elimination of interferences and deoxidation effects with carbon black in flame atomic absorption spectrophotometry of metals. This report deals with the flame atomic absorption-spectrophotometry of metals by direct atomization of their sulfides dispersing in water and with the deoxidation effect of metal sulfide or sulfur powder on metal oxides suspended in water. Generally, metal sulfide was able to be atomized readily than metal oxide, being allowed to be determined by direct flame atomization of the sulfide suspended water. Although a direct atomization method for metal oxides dispersing in water was less sensitive, the sensitivity was improved by the addition of metal sulfides or sulfur powder to the sample solution. The addition of sulfur powder was more effective in this respect. Interference of hydroxide which is formed in high pH solutions was also eliminated by passing hydrogen sulfide through the sample solution to yield metal sulfides from hydroxides.

View full abstract

Relative sensitivities of electron capture detector (ECD, ⁶³Ni) for various phthalates (PAE) and other compounds were measured at the detector temperature of 230, 290 and 320°C (Table 1). Relative sensitivities of phthalate esters having long alkyl chain were higher than those of shorter ones at the detector temperature of 320°C. The difference in relative sensitivities of phthalate esters was small at the lower detector temperature. Among three kinds of dimethyl phthalate isomers (o-, m- and p-substituted compounds), the relative sensitivities were in the order of p o m. The relative sensitivities of benzoates (monosubstituted compounds) were lower than those of the phthalate esters (disubstituted compounds). Temperature dependence of electron capture coefficients (K) for these compounds was determined with D. C. mode. K values of phthalate esters ordinarily increase with decreasing detector temperature except for diallyl phthalate, as shown in Figs.2-4. Arrhenius plots of KT^3/2 vs.1/ T result in positive slopes. These phenomena show that electron capture reaction of these compounds proceeds non-dissociatively. Electron affinities (EA^t) were calculated from the magnitude of positive slope (Fig.7). EA^t value of DBP was the largest amomg the phathalate esters containing straight alkyl chain. EA^t values of the phathalate esters containing branched alkyl chain were larger than those for the straight alkyl chain types. EA' values of three kinds of dimethyl phthalate isomers were in the order of p o m. These results may be attributed to the degree of the resonance stabilization of anion radical which is formed by capturing electron.

View full abstract

High boiling impurities in reagent grade acetonitrile were identified and determined by a gas chromatograph-mass spectrometer.
Acetamide, butanedinitrile, pentanedinitrile, di-t-butyl methylphenol, chlorobenzene were identified as impurities from their electron impact and chemical ionization mass spectra. The identification was confirmed with gas chromatographic retention data for reference substances.
A small amount of impurities in acetonitrile was determined sensitively and selectively without any preconcentration of the impurities in the setting of the multiple ion selector (MIS) to their characteristic fragments. For example, acetamide, whose gas chromatographic separation from acetonitrile was incomplete, was selectively determined by setting MIS at m/e=59. The minimum detectable amount of impurities was found to be 1x10^-9-1x10^-11g.
The main impurities with high boiling points in acetonitrile were acetamide and dinitriles, and the minimum detectable amount of these was found to be 6-40 ppm in several kinds of acetonitrile. In the case of using acetonitrile as an extraction solvent, trace impurities containing nitrogen in acetonitrile may give some interference in the determination with a flame thermionic detector.

View full abstract

Lead isotope ratios ²⁰⁶Pb/²⁰⁴Pb, ²⁰⁷pb/²⁰⁴Pb, ²⁰⁶/²⁰⁴Pb, ²⁰⁷Pb/²⁰⁶Pb and ²⁰⁸Pb/²⁰⁶Pb in Japanese galena ores and archaeological bronze objects were determined by a Hitachi RMU-6 mass spectrometer using a rhenium single filament as a surface ionization device. Basic experi- mental conditions including detection limit, fractionation effect, memory effect, etc. were examined, and the accuracy of determination was checked using the CIT shelf standard No.1 (Table 2). Archaeological bronze objects were dissolved in nitric acid and lead was extracted by the dithizone method using specially purified reagents in a so-called clean labora- tory. When 0.5, ug lead was loaded on the rhenium filament with phosphoric acid and silica gel as stabilizers, an ion current of 10^-13-10^-15 A due to Pb⁺ was obtained and maintained stable for several hours. Coefficients of variation found for the isotope ratios ²⁰⁷Pb/²⁰⁶Pb and ²⁰⁸Pb/²⁰⁶Pb were 0.1-0.5%. Lead isotope ratios are given for 17 Japanese galena ores (Table 5) and for archaeological bronze objects such as bronze bells, halberds (Yayoi period), Horyuji pagoda spire (7 th century), and Northern Sung coins (11 th century) (Table 7). A close resemblance of the isotope ratios was found between Japanese galena ores and some Japanese bronze objects of the 7 th century, suggesting the use of the former as raw materials of the latter.

View full abstract

Molecular orbital calculation by the CNDO/2 method was carried out on the several aldehyde (formaldehyde, acrylaldehyde, benzaldehyde, polyenals, and glyoxal)-water systems to elucidate the hydrogen bond energies for the 1: 1 and 1: 2 aldehyde-water complexes, the conformations of hydrogen bonded complexes and the equilibrium constants for the hydrogen bond formation at room temperature.
The calculated hydrogen bond energies ranged from 2.9 to 3.7 kcal/mol after an appropriate correction and these values agreed with the observed values for the ketone-alcohol systems in numerical order. The CNDO/2 method showed the favorable conformation for the hydrogen bonded 'complex of aldehyde with water to be the structure with the values from 40° to 55° for the angle between the carbonyl and hydroxyl groups and with 1.6 A for the equilibrium; distance between the oxygen atom of formyl group and hydrogen atom of hydroxyl group. As it is hard to calculate theoretically an entropy change in the hydrogen bond formation, the values of entropy change from -10 to -12 cal/K. mol measured for the ketone-alcohol system were used to estimate the equilibrium constants for the hydrogen bond formation reaction between these aldehydes and alcohol. The calculated equilibrium constants were about 1.0 at 25°C.
The aldehyde with: the electron donating group such as vinyl and phenyl was stronger than formaldehyde but glyoxal which has electron attracting groups was weaker than formaldehyde in hydrogen bonding strength.
The hydrogen bond energy of the polyenal-water system increased with an increase of the conjugation of polyenal.

View full abstract

Alkyl(2-hydroxy-5-methylbenzyl) dimethylammonium halides were prepared by Menschutkin reaction between 2-(dimethylaminomethyl)-p-cresol and alkyl halides (alkyl carbon number: 1, 2, 3, 8, 10, 12).
Simultaneously, bis(2-hydroxy-5-methylbenzyl) dimethylammonium halide and dialkyldimethylammonium halides were obtained as by-products. It was assumed that the recombination reactions of the quaternary ammonium salts occurred.
Antibacterial and antimildew properties were tested for these quaternary salts, and it was proved that the quaternary salt having dodecyl group as an alkyl chain was predominant as an antimicrobial agent. Introduction of phenolic hydroxyl group to quaternary ammonium compound enhanced these properties.

View full abstract

The reactions of nitrile oxides with various polysubstituted p-benzoquinones forming dioxa- zole derivatives have been studied kinetically and the results were discussed in terms of sub- stituent parameters of the quinone substituents. The activation parameters obtained (Table 1, 2 and 4) are of an order characteristic of a multi-center addition. The reaction ratesre are shown to be correlated to reactivity parameters defined as S where a₁ and R⁰_R inductive and resonance parameters of the substituents at i-position, respectively, and a was tentatively assumed to be unity (Fig.3). The slope is 2.3, which implies that the reactions proceed througth nucleophilic attack of the nitrile oxide to the carbonyl carbon atom of quinones. The reactivity parameter is shown to be particularly useful to predict selective reactivity of the carbonyl groups in p-benzoquinones having two different carbonyls.

View full abstract

In order to study the structure of coal, ¹H pulse NMR and X-ray diffraction have been measured for several ranks of coal and their derivatives.
Spin-spin relaxation time measured by pulse NMR suggested that there were different relaxation regions in every coal ranks, pyridine extracts and residues from the parent coal. Two relaxation regions (T_2r T_2m) was confirmed to be correspond to an immobile region and relatively free one, respectively (Table 2).
The diffuse X-ray scattering profiles obtained from the same specimens was analyzed using Fourier transformation for [002] band. The average number (n) and the fraction for stacking (P) in the layer of carbon network changed with the advance of coal rank from Taiheiyo brown coal to Hongei anthracite (Table 3).
The difference of volume fraction in the immobile region calculated by the methods of NMR and X-ray (F(T_2r)-P) coincided with the degree of cross-linking among the structural unit (Fig.3).

View full abstract

Interaction of the copolymer of maleic acid and styrene (MASt) with Acridine Orange (AO) was studied by means of spectroscopic and pH titration methods.The shape of the absorption spectrum of MASt-AO system depended on C_p/C_d (polymerto-dye concentration ratio) and the conformation of MASt. For C_p/C_d10, the binding of AO with MASt was found to be complete. The absorption maximum of the monomeric AO bound to MASt in the compact form shifted to higher wavelength than the free AO, and the intensity at the maximum was found to increase with increasing the C_p/C_d ratio. These results support the existence of the hydrophobic bond originated from the interaction between phenyl groups.
The absorbance ( I ) of the bound monomeric AO was estimated by use of the spectrum simulation method. A plot of I against α₁ (degree of neutralization of the primary carboxyl groups in MASt) yielded a reverse sigmoid curve demonstrating the conformational transition of MASt from the compact form to the loose coil one. pH titration results indicated that the bound AO shifted the transition region of MASt to higher values of α₁.

View full abstract

Packed bipolar cell, in which particles having electrical conductivity were packed between main anode and cathode and a sufficiently high field was applied to make each particle to be a bipolar electrode, was tested for the electrolytic treatment of waste waters containing heavy metal ions and/or cyanide ion. When CuSO₄ solution was electrolyzed in a bipolar cell packed with activated carbon particles, metallic copper was deposited on cathodic part of each particle with rapid decrease in Cu²⁺ in the solution. Concentration of Cu²⁺ reached ca.2 mg/l, but did not diminish further, probably because of anodic dissolution of deposited copper due to some particles being unsettled by the action of evolved gas. In the electrolysis of KCN solution, concentration of CN^- decreased rapidly at first, but as it became low, it decreased slowly. Rate of decomposition of CN^- was high when CuCN was added. Thus, concentration of CN^- decreased from 1000 mg/l to O.3mg/l during 4 hours under the operating conditions. It was suggested that a certain copper complex showed a catalytic effect on anodic oxidation of CN^-. A stable complex, Fe (CN)₆^8-, was also removed from the solution rapidly. Applicability of the packed bipolar cell to waste water treatment was discussed.

View full abstract

The solubility of iodates of Ca ( ii ), Sr ( ii ) and Ba ( ii ) in N, N-dimethylformamide-water mixtures has been determined iodometrically at 20°, 25° and 30°C.
The logarithm of the solubility of the sparingly soluble salts decreased almost linearly with the reciprocal of the dielectric constant of the solvents, as expected from the Born equation. Factors which cause the deviation from the linearity were discussed. The salvation radius was computed with the observed data and the Born equation.

View full abstract

Some metal fluorides showed the catalytic activity for the dehydrosulfurization of 2-propanethiol and the order of the catalytic activity at 300°C was AlF₃, NiF₂ CrF₃ CoF, , FeF₂. However, the catalytic activities of these metal fluorides except AlF₃ decreased with increasing pulse number. The dehydrosulfurization of 2-propanethiol over AlF₃ was hindered by pyridine. The analogous change in the catalytic activity of AlF, due to calcination temperature was observed in the dehydrosulfurization of 2-propanethiol or the dealkylation of cumene. Thus, it was concluded that the dehydrosulfurization of 2-propanethiol over AlF₃ proceeded in terms of the carbonium ion mechanism which is concerned with a proton on the surface of AlF₃.

View full abstract

For the thermochemical production of hydrogen from water, the vapor-liquid equilibrium for HBr-H₂SO₄-H₂0 system has been investigated by using a Othmer still under atmospheric pressure. The work reported here is limited to a dilute composition range, that is a hydro- bromic acid concentration range below the azeotropic composition.
The vapor-liquid equilibrium diagram for this ternary system is shown in Fig.3. The concentration of H₂SO₄ found in the condensate, which is attributed to the following reversible reaction, is also shown in Fig.3.

H₂SO₄+2HBr⇔2H₂O+S0₂+Br₂
The boiling point diagram is shown in Fig.4.

View full abstract

A voltammetric detector with a platinum gauze electrode as a working electrode has been developed and used for a high performance liquid chromatography. Performance of this detector was evaluated with o-nitrophenol as a depolarizer in the electro-reduction.
A linear relationship between current and the concentration of the phenol was obtained in the concentration range of 2x10^-9-2x10^-6g and the minimum detectable amount of o-nitrophenol was 2x^-9
A voltammetric detector with a mercury-plated platinum gauze electrode has also been developed. With this detector, final current raise could be extended to more negative potential than that for the platinum electrode, and background current reduced to about one-half that of the platinum electrode. This mercury-plated type detector offers promising applications to compounds with high negative reduction potentials.

View full abstract

The reaction rates of six tris(alkylthio)stibines with acetic anhydride were studied by monitoring the decrease in the amount of acetic anhydride utilizing IR spectrometer. The reaction of tris(alkylthio)stibine with acetic anhydride was 100 times slower than that of antimony alkoxide with the same alkyl substituent. The correlation with Taft's equation was fairly good, and the reaction constant was calculated to be positive. These results suggest that the electrophilic attack of the antimony atom on the ether oxygen of acetic anhydride is the rate determining step where the interaction between the carbonyl group of acetic anhydride and the sulfur atom of the alkylthio group is involved.

View full abstract

Isomerization and hydration of a-longipinene [1] and longicyclene [2] by the action of equimolar mono-, di- or trichloroacetic acids have been studied under anhydrous conditions. Both [1] and [2] yielded isomerization products, longifolene [3] and isolongifolene [4], along with hydration products, longicamphene hydrate [5], longi-R-fenchyl alcohol [6] and longiborneol [7]. Hydration of [1] to give [6] as a major product amounted to 92% of the hydration products under optimum conditions. The compound [7] was the major product (57% at best) in the hydration of [2].

View full abstract

When dry air was blown into a stirred mixture of a-longipinene [1] and polar aprotic solvents (DMS0 and DMF) for 8-100 hr at 130±5°C, oxidation of [1] took place to give longiverbenone [5] as a major product, longicamphene hydrate [6], longi-B-fenchyl alcohol [7], longiborneol [8] and 9-oxoisolongifolene [9]. A similar oxidation of longicyclene [2] yielded longiborneol [8] as a major product, along with [6], [7] and [9] as minor products.
The polar aprotic solvents (DMSO, DMF) proved to be valuable to oxidation of terpenes.

View full abstract

Oxidation of caryophyllene with trilead tetraoxide in the mixture of acetic anhydride and glacial acetic acid at 60°C afforded the following products:dihydrocaryophyllen-5-one [1], caryophylla-4, 8 (13) -dien-2-ol [2], isodihydrocaryophyllen-5-one [3], dihydrocaryophyllen-4-ol[4], caryophylla-4, 8 (13) -dien-12-ol [5], caryophylla-4 (12), 8 (13) -dien-5 a-ol [6], caryo- phylla-4 (12), 8 (13)-dien-5 R-ol[7], caryophylla-3, 8 (13) -dien-5 a-ol [8], and caryophylla3, 8 (13) -dien-5 13-ol [9].
Oxidation of caryophyllene with lead dioxide in glacial acetic acid at 114-115°C afforded the products [2], [3] and [5]-[9].
Their structures were assigned on the basis of their IR, NMR, and MS spectra.

View full abstract

The base-catalyzed elimination of hydrogen bromide from 1, 2-dibromo-1-fluoroethane yielding bromofluoroethylenes was carried out under various conditions (Table 1). In all cases, the formation of 1-bromo-2-fluoroethylenes [3] predominated over that of 1-bromo-1-fluoroethylene [2]. However, the use of stronger bases and protic solvents increased the ratio [2]/[3]. The results are discussed in reference to the plausible reaction mechanism (Fig.2). Of the Z and E isomers of [3], the former was present overwhelmingly due presumably to the thermodynamic stability.

View full abstract

The reaction of 3-methyl-2-butenenitrile [1] with prenyl chloride (1-chloro-3-methy1-2- butene) was investigated.2-Isopropylidene-5-methyl-4-hexenenitrile [2] was obtained in 55% yield by action of potassium hydroxide in dimethyl sulfoxide. The reaction by the addition of potassium iodide or dibenzo-18-crown-6 in benzene was also carried out (Table 1). The byproducts were shown to be (Z)-3, 7-dimethyl-2, 6-octadienenitrile [3], (E)-3, 7-dimethyl-2, 6-octadienenitrile [4] and 2-isopropenyl-5-methyl-2-(3-methyl-2-butenyl)-4-hexenenitrile [5] The reaction of 3-methy1-3-butenenitrile [7] with prenyl chloride was also examind.

View full abstract

The hydrolysis of d- and l-p-nitrophenyl a-methoxyphenylacetate and p-nitrophenyl esters of N-benzyloxycarbonyl a-amino acid catalyzed by surfactants derived from n-ephedrine has been examined.
No stereoselectivity was observed under the experimental conditions in which Bunton claimed to have obtained the selectivity. Small but not negligible stereoselectivity was found in the hydrolysis of p-nitrophenyl N-(benzyloxycarbonyl) phenylalanine in the surfactant micellar system.

View full abstract

(+)-1-p-Menthen-9-al [5], a component of Bulgarian rose oil, was synthesized from (+)-8-hydroxy-1-p-menthen-9-y1 acetate [2] and (+)-1-p-menthene-8, 9-diol [3], which were provided by oxidation of limonene [1] with lead tetraacetate.
The acetate [2] and the related alcohol [3] were treated with lead (ii) acetate in glacial acetic acid to give [5] and (+)-1, 8-p-menthadien-9-ol [10] in a ratio of 63/37 and 75/25 respectively.
The title compound was obtained in ca.40% yield from [2] and ca.50% yield from [3].

View full abstract