摘要:

AbstractThe stablest intermediate product formed in the oxidation of cyclohexanol and cyclohexanone is 6‐hydroxyimino‐6‐nitro hexanoic acid (nitrolic acid). In the temperature range investigated it yields over 90% of adipic acid and N2O. In addition, a small amount of a still unidentified by‐product is formed at low temperatures; upon heating, the latter gives also adipic acid.The decomposition reaction appeared to be first‐order in nitrolic acid. Nitric acid greatly influences the reaction rate; in the range of concentrations up to 50% HNO3, the first‐order rate constant was found to be linearly dependent on the hydrogen‐ion activity. The activation energy of the reaction amounts about 24

ISSN:0165-0513    

DOI:10.1002/recl.19630820502

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractThe reaction velocity of the oxidation of cyclohexanol and cyclohexanone with nitric acid (without a catalyst) can be calculated from the chromato‐graphically measured change in the concentration of some of the reaction products: nitrolic acid and adipic acid.The oxidation reaction appeared to be first order in cyclohexanone, which rapidly forms in the oxidation of cyclohexanol. The oxidation rate can be calculated by means of a simple empiric formula.The catalysts NH4VO3and Cu(NO3)2do not affect the oxidation rate proper. The rate at which Dione decomposes into adipic acid (kv) in the presence of vanadate can be calculated from the increase of the adipic acid concentration. If vanadate is absent, an impression of the rate at which Dione is further oxidized into by‐products (kH) can be obtained from the increase of the glutaric acid and succinic acid concentrati

ISSN:0165-0513    

DOI:10.1002/recl.19630820503

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractSome new diacylglycerol‐iodohydrins are describe

ISSN:0165-0513    

DOI:10.1002/recl.19630820504

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractExperiments are reported on the association number of magnesium bromide, diethylmagnesium, mixtures of these two compounds, the Grignard reagent prepared from magnesium and ethyl bromide and mixtures of this Grignard reagent with magnesium bromide, all dissolved in pure diethyl ether at concentrations from 10−3to 10−2molar and measured at the same temperature.No trace of the equilibrium:\documentclass{article}\usepackage{amssymb}\pagestyle{empty}\begin{document}${\rm Et}_{\rm 2}{\rm Mg}+{\rm MgBr}_2\leftrightarrows{\rm Et}_2{\rm Mg}.{\rm MgBr}_2$\end{document}was observed.Only one magnesium atom is incorporated in the molecules of the Grignard reagent, even in the presence of a large amount of magnesium brom

ISSN:0165-0513    

DOI:10.1002/recl.19630820505

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractAssociation numbers of magnesium compounds in tetrahydrofuran have been investigated. One Mg‐atom is incorporated in the molecules of the Grignard reagent, of MgBr2, and of Et2M

ISSN:0165-0513    

DOI:10.1002/recl.19630820506

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

Abstract3‐Benzyl, 3‐α‐methylbenzyl, and 3‐α‐dimethylbenzylthiophene were prepared from the sodium salts of the corresponding benzylsuccinic acids and phosphorus trisulphide in 20–40% yields. The succinic acids were obtained through side‐chain addition of toluene, ethylbenzene, and isopropylbenzene, respectively to m

ISSN:0165-0513    

DOI:10.1002/recl.19630820507

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractThe synthesis is described of two isomeric lysophosphatidylethanolamines, containing the fatty acid residue in the γ‐ and β‐ester position, respectively. The preparation of the (β‐stearoyl)‐DL‐α‐lysophosphatidylethanolamine was accomplished by two procedures. According to the first method developed, a silver iodide interchange reaction was carried out between γ‐O‐benzyl‐β‐stearoylglycerol‐α‐iodohydrin and silver benzyl 2‐phthalimidoethyl phosphate. This procedure was also applied for the synthesis of (γ‐stearoyl)‐DL‐α‐lysophosphatidyl‐ethanolamine by starting from γ‐stearoyl‐β‐O‐benzylglycerol‐α‐iodohydrin. A second method involved the preparation of silver benzyl γ‐O‐benzyl‐β‐stearoyl‐α‐glycerol phosphate which was coupled with 2‐iodoethylphthalimide. This pathway also furnishes several intermediates which are suitable for the preparation of other types of lysophosphatides. A distinction between both structurally isomeric lysophosphatidyl‐ethanolamines by enzymic means proved to be possible. Phospholipase A from snake venom was shown to release the fatty acid constituent from the β‐acyl i

ISSN:0165-0513    

DOI:10.1002/recl.19630820508

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractA method is described for the preparation of silver benzylN‐t‐butyloxycarbonyl‐2‐aminoethyl phosphate. A reaction between this substance and γ‐palmitoyl‐β‐linoleoylglycerol‐L‐α‐iodohydrin, after removal of the protecting groups, furnished γ‐palmitoyl‐β‐linoleoyl‐L‐α‐p

ISSN:0165-0513    

DOI:10.1002/recl.19630820509

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractWhen solutions of trichloromethylsulfenyl chloride, Cl3CSCl, in alkanes are exposed to sunlight, alkyl chlorides, hydrogen chloride and hexachlorodimethyl disulfide are formed:\documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm RH}\, + \,2\,{\rm Cl}_3 {\rm CSCl}\, \to \,{\rm RCl}\, + \,{\rm HCl}\, + \,{\rm Cl}_3 {\rm CSSCCl}_3 .$$\end{document}An advantage of this novel chlorination method is the high selectivity, which is even further increased in the presence of benzene. The disulfide may be reconverted to the sulfenyl chloride by molecular chlorine in a separate step.A radical chain mechanism is proposed for the reaction in which trichloromethylthiyl and alkyl are the chain‐carrying radical

ISSN:0165-0513    

DOI:10.1002/recl.19630820510

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY

摘要:

AbstractThe photochlorination of some alkyl chlorides with trichloromethylsulfenyl chloride has been investigated. Product distributions and reactivities relative to alkanes were determined. The results show the importance of polar effects and can be correlated with the polar substituent constants σ*. A chlorine atom reduces the reactivity of a neighbouring carbon‐hydrogen bond by a factor of 45. The reactivities at other positions correspond to a loss factor of 1.6. A methyl group exerts a slight activating polar effect.A correlation with NMR chemical shifts suggests that the differences in reactivity of methylene groups in hydrocarbons, as reported in Part II2, are also due to polar effec

ISSN:0165-0513    

DOI:10.1002/recl.19630820511

出版商:WILEY‐VCH Verlag    

年代:1963

数据来源: WILEY