摘要:

AbstractAn X‐ray diffraction study of propenylp‐tolyl sulfone has shown that the S‐CH = CH‐CH3group has thetransconfiguration rather than thecisconfiguration assumed byBacker, Stratingan

ISSN:0165-0513    

DOI:10.1002/recl.19730920402

出版商:WILEY‐VCH Verlag    

年代:1973

数据来源: WILEY

摘要:

AbstractThe catalysts isolated from the reaction mixtures of the molybdenum‐catalysed epoxidations of various olefins withtert‐butyl hydroperoxide were all found to be soluble Mo(VI)‐1,2‐diol complexes. The structure of the diol complex is directly related to the structure of the olefin being epoxidized and is independent of the type of molybdenum compound originally added as the catalyst. Separate experiments have shown that the diol complexes are formedin situby reaction of the molybdenum catalyst with the epoxide in the presence of the hydrop

ISSN:0165-0513    

DOI:10.1002/recl.19730920403

出版商:WILEY‐VCH Verlag    

年代:1973

数据来源: WILEY

摘要:

AbstractThe method for the estimation of standard chemical potential differences (Δμ°) of single ions, described previously, is applied to the transfer from water to 1,4‐dioxane‐water and acetic acid‐water

ISSN:0165-0513    

DOI:10.1002/recl.19730920404

出版商:WILEY‐VCH Verlag    

年代:1973

数据来源: WILEY

摘要:

AbstractThe Koch‐Haaf carboxylation of a series of 1‐alkylcyclohexanemethanols and 1‐(1‐alkylcyclohexane)ethanols has been studied. In the initial cation the 1‐alkyl group always migrates into the side chain, yielding tertiary carboxylic acids. An exception is the carboxylation of 1‐(1‐adamantane)ethanol, which gives the corresponding secondary acid besides 3‐ethyladamantanecarboxylic acid. The latter compound is formed probably from the initial carbonium ion after a bimolecular hydride shift.The carboxylation of 1‐methyl substituted spiro[2.5]octanes has been investigated. Steric factors appear to determine the edge of the cyclopropane ring which is open

ISSN:0165-0513    

DOI:10.1002/recl.19730920405

出版商:WILEY‐VCH Verlag    

年代:1973

数据来源: WILEY

摘要:

Abstract“positive halogen” compounds were found to induce the decomposition oft‐butyl hydroperoxide (I) in the dark. In this Cl2O proved to be particularly effective, liberating oxygen from I instantaneously at 0°. At temperature between −80° and −30°, two oxygen‐rich intermediates could be observed with the aid of NMR‐spectroscopy.t‐Butyl peroxyhypochlorite(But‐O‐O‐Cl) was formed immediately;di‐t‐butyl trioxide(ButOOOBut) apparently resulted from a slower reaction, found to be promoted by alkali. By using a solution of di‐t‐butyl trioxide thus obtained, the polymerization of methyl acrylate could be i

ISSN:0165-0513    

DOI:10.1002/recl.19730920406

出版商:WILEY‐VCH Verlag    

年代:1973

数据来源: WILEY

摘要:

AbstractThe autoxidation of 3‐hydroxybutan‐2‐one is studied in acidic 50 vol. % aqueous ethanol. The reaction is catalyzed by ferrocene. The rate determining step of the ferrocene catalyzed reaction is the acid catalyzed enolization of the substrate. Subsequently, both the enol‐form of the substrate and ferrocene are oxidized by

ISSN:0165-0513    

DOI:10.1002/recl.19730920407

出版商:WILEY‐VCH Verlag    

年代:1973

数据来源: WILEY

摘要:

AbstractESR spectra show that pyrimidine dimerizes to 4,4′‐bipyrimidine in dimethyl‐formamide (DMF). The coupling constants in 4,4′‐bipyrimidine have been determined. Cyclovoltammetric experiments indicate that the disappearance of the mononegative ion of pyrimidine cannot be described by a simple mono‐ or bimolecular deactivation. The heterogeneous reaction rate constants (ks.h) have been determined by a.c. polarography. It can be deduced from the reduction potentials that dimerization of pyrimidine cannot be used for the synthesis of 4,4′

ISSN:0165-0513    

DOI:10.1002/recl.19730920408

出版商:WILEY‐VCH Verlag    

年代:1973

数据来源: WILEY

摘要:

AbstractThe acid catalyzed hydrolysis of ethoxypropadiene has been studied in aqueous solution. The reaction is general acid catalyzed and catalytic constants for carboxylic acids conform to the Brønsted relation with an exponent α = 0.62. The average value of the solvent isotope effectk(H3⊕)/k(D3⊕) is 3.05 ± 0.11. These values are similar to corresponding values for vinyl ethers. Proton transfer from acid to substrate is rate‐determining. Zucker‐Hammett and Bunnett parameters suggest, that water is not covalently bound in the transition state of the rate‐dete

ISSN:0165-0513    

DOI:10.1002/recl.19730920409

出版商:WILEY‐VCH Verlag    

年代:1973

数据来源: WILEY

摘要:

AbstractNormal coordinate calculations of vinyl fluoride, chloride, bromide and iodide are reviewed. Modified Valence Force Fields are reported, by making use of published vibrational data of all deuterated isotopic species and observed Coriolis constants. The iterative least‐squares procedure used adjusts observed and calculated frequencies and second order Coriolis constants simultaneously, so we introduced a mutual dependency between the two vibrational species A′ and A″.Our calculations suggest frequency reassignments for some isotopic mole

ISSN:0165-0513    

DOI:10.1002/recl.19730920410

出版商:WILEY‐VCH Verlag    

年代:1973

数据来源: WILEY

摘要:

AbstractEvidence is presented that the amination of 4‐chloro‐2,6‐diphenylpyrimidine with potassium amide in liquid ammonia into the corresponding 4‐amino compound occurs to the extent of about 45% by the ANRORC mechanism. In the amination of the 4‐iodo‐ and 4‐fluoro derivatives of 2,6‐diphenylpyrimidine, however, the ANRORC mechanism is not operative at all. The amination of 5‐bromo‐4‐chloro‐2,6‐diphenylpyrimidine into 4‐amino‐5‐bromo‐2,6‐diphenylpyrimidine occurs to the extent of about 18% by the ANRORC mechanism. The synthesis of 5‐bromo‐4‐chloro‐2,6‐diphenyl‐[1(3)‐15N]pyrimidine and of the 4‐fluoro, 4‐chloro and 4‐iodo deriva

ISSN:0165-0513    

DOI:10.1002/recl.19730920411

出版商:WILEY‐VCH Verlag    

年代:1973

数据来源: WILEY