摘要:

AbstractReduction of benzyl bromide, benzal chloride and benzotrichloride with a commercial nickel powder at 150°Cgave bibenzyl,trans‐stilbene, andtrans‐1,2‐dichlorostilbene. The reaction intermediates 1,2‐dichloro‐1,2‐diphenylethane for benzal chloride and 1,1,2,2‐tetrachloro‐1,2‐diphenylethane for benzotrichloride were also isolated or detected by NMR spectroscopy. Dehalogenation of these intermediates by the nickel metal or by KI yielded the correspondingtransisomer as the main product. A commercial cobalt powder also reacted with these organic halides leading to similar results. Mechanisms for these reac

ISSN:0009-4536    

DOI:10.1002/jccs.198600026

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractComplex equilibria of DCPHD with proton and Ni2+, Sm3+, and Yb3+ions has been measured in various mixed aqueous solvents, viz: isopropanol‐water, acetone‐water, ethanol‐water, and methanol‐water. Based on potentiometric equilibrium measurements of hydrogen ion concentration at 30°C, ionic strenght 0.10M(KNO3) and in the above various mixed aqueous solvents, the values of the protonation constants of DCPHD and the stability constants of DCPHD with Ni2+, Sm3+, and Yb3+have been evaluated. The variation of protonation and stability constants with the inverse of dielectric constant or mole fraction of the solvent was studied. Application of Fuoss expression and consideration of electrosatic and non‐electrostatic effects are made to explain the values of the

ISSN:0009-4536    

DOI:10.1002/jccs.198600027

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractA procedure is described for the trace analysis of nickel using the liquid‐liquid extraction of nickel acenaphthenequinone dioxime complex with molten naphthalene followed by solid‐liquid separation. Nickel complex cannot be extracted into any non‐aqueous organic solvents, but can be quantitatively extracted into molten naphthalene. It is very stable at high temperature and is dissolved in the mixed solvent (HNO3‐DMF). The absorbance of the solution was measured at 231.5nmagainst a reagent blank. Beer's law is followed in the concentration range of 5–100 μgof nickel in 10mlof the final solution. The sensitivity for 1% absorption is 0.155 μg/mlnickel. The relative standard deviation is 1.0% for ten replicate determinations of 60 μgof nickel. The interference of various ions has been studied and the method has been applied to the determination of nickel in alum

ISSN:0009-4536    

DOI:10.1002/jccs.198600028

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractA comparative study of some quantitative methods has been undertaken. Chemical and colorimetric procedures have been developed for the determination of IS4: 4‐(anisylideneamino) antipyrine. The non‐aqueous titration and the nitritometric techniques were used. The formation of colored azo dye derivatives through diazotization and coupling with phenolic and amine reagents has been the basis of the colorimetric determination. Statistical analysis of the results has shown that a good agreement of the results has been found on applying the proposed methods to 4‐aminoantip

ISSN:0009-4536    

DOI:10.1002/jccs.198600029

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe title compound (7) was synthesized in six steps from 1,8,9,10‐tetrachloro‐11,11‐dimethoxy‐endo‐tricyclo[6.2.1.02,7]undeca‐4,9‐diene‐3,6‐dione (4) in an overall yield of 36%. The key intermediate, 1,8,9,10‐tetrachloro‐11,11‐dimethoxy‐endo‐tricyclo‐[6.2.1.02,7]undeca‐3,5,9‐triene (12), obtained from4by reduction, mesylation and then 1,4‐elimination, was allowed to react with diethyl azodicarboxylate to afford the Diels‐Alder adduct16. Photochemical closure of16, followed by hydrolysis and decarboxylation, gave the title compound.The title compound failed to give either the homopentaprismanone derivative3or the diene9by the photochemical or ther

ISSN:0009-4536    

DOI:10.1002/jccs.198600030

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractTwelve compounds each having a six membered Si‐contained heterocycle, have been successfully synthesized. Of these eleven compounds have never been reported in the literature. The structures were confirmed by Spectral analysis and elementary analysis. The stability and properties of these compounds is also discusse

ISSN:0009-4536    

DOI:10.1002/jccs.198600031

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractVarious kinds of α‐halo ketones readily reacted with disodium (dimercaptomethylene)malononitrile to give the corresponding 34‐diamino‐2,5‐diacylthieno‐[2,3‐b]thiophenes in good to excellent yields. The reaction was successfully extended to the synthesis of a thienothiophene derivative having two sydnone rings by using the 4‐(bromo

ISSN:0009-4536    

DOI:10.1002/jccs.198600032

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractSixteen compounds were isolated from the bark ofChamaecyparis formosensisMatsum. These compounds include four categories: (a) long‐chain alcohols, acids and esters, (b) sterols and their glucosides, (c)o‐methoxyphenol and related compounds, (d) diterpenes of abietane, pimarane, secoabietane and totar

ISSN:0009-4536    

DOI:10.1002/jccs.198600033

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractA gas chromatography/mass spectrometry (GC/MS) coupled system has been established for the confirmatory identification of abnormal urinary organic acids in inherited metabolic diseases. Samples of patient urines were extracted with an organic solvent and trimethylsilylated (TMS). A mass spectra of gas chromatographically separated TMS derivatives can be obtained using the GC/MS coupled system with a single analytical run. Those compounds with close methylene units (e.g., 4‐hydroxyphenylacetaic acid and phenylpyruvic acid) in the gas chromatograph can be identified by their specific mass spectra. The results indicate that this GC/MS system is a powerful method for identifying abnormal urinary organic acids. These acids can be identified by comparison with authentic mass spectra established in our laboratories or with mass spectra files from other sources or they can be directly identified by analysis of the mass spectrum. By using this system, we were able to make positive identification of several inherited metabolic diseases found in Chinese patients, including phenylketonuria, propionic acidemia, and methylmalonic aciduria. This GC/MS system is a powerful tool for the diagnosis of inherited metabolic disease

ISSN:0009-4536    

DOI:10.1002/jccs.198600034

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe changes in the surface areas of copper and zinc oxide have been measured to evaluate the individual rates of sulfur coverage of each of these phases during catalyst exposure to sulfur‐containing gas. Zinc oxide surface areas have been measured by CO2adsorption and copper surface areas by measurement of the nitrogen formed by exposure to nitrous oxide. The surface areas of both components decreased exponentially with increasing exposure time to the sulfur‐containing gas. The zinc oxide component is more sulfur‐resistant than copper. This is attributed to either kinetic limitation or the more stable surface sulfides of

ISSN:0009-4536    

DOI:10.1002/jccs.198600035

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY