摘要:

EPR‐Untersuchungen zur Komplexbildung von Cr(V) mit Thenoyltrifluoraceton und einigen Monothio‐β‐diketonen in nichtwäßrigem MediumEs wurde die Komplexbildung von Cr(V) mit Thenoyltrifluoraceton und einigen Monothio‐β‐diketonen in Ethylalkohol, Acetonitril, Dimethylformamid, Formamid, Dimethylsulfoxid und Hexamethylphosphortriamid untersucht. Mittels EPR‐Spektroskopie wurde gefunden, daß Anzahl und Konzentration der Cr(V)‐Komplexe vom Lösungsmittel abhängen und mit steigender Donorzahl des Lösungsmittels zunehmen. Entsprechend NMR‐Untersuchungen koordinieren Lösungsmittelmoleküle am Cr(V). Ein Reaktionsschema zur Bildung von Cr(V) aus

ISSN:0021-8383    

DOI:10.1002/prac.19803220502

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

Heterocyclen mit potentiellen Heterodienen. III. Synthese und Cycloaddition von 4‐Carbomethylen‐3‐methyl‐1‐phenyl‐5‐pyrazolen4‐Carbomethylen‐3‐methyl‐1‐phenyl‐5‐pyrazolone (4a, 4b) entstehen aus 2‐Pyrazoline‐, 5‐dion 2 und Benzoylmethylen‐ bzw. Carbomethomethylen‐triphenylphoranen (3abzw.3b) durch Wittig‐Synthese.4a, 4bwurden durch IR‐und NMR‐Spektren gekennzeichnet. Sie reagieren „in situ”︁ mit Ethylvinylether zu den eis und tran

ISSN:0021-8383    

DOI:10.1002/prac.19803220503

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

Synthese und spektroskopische Charakterisierung einiger neuer 3,5‐Bisarylierter‐2‐pyrazolinderivate. IIDurch Kondensation von Hydrazin bzw. substituierten Hydrazinen mit Chalkonen wurden einige neue 3,5‐bisarylierte‐2‐pyrazoline4, 7–18dargestellt.Bromierung des Pyrazolins4liefert das 4‐Brompyrazol20.Die Verbindungen wurden durch hochauflösende Massenspektrometrie, UV‐, IR‐ und H‐NMR‐Spekt

ISSN:0021-8383    

DOI:10.1002/prac.19803220504

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

Concerning the Calculation of HLB Values of Isomeric and Substituted Alkane SulphonatesBased on LIN's hydrophobicity index HLB values have been calculated for the isomeric dodecane sulphonates and some substituted pentadecane‐1‐sulphona

ISSN:0021-8383    

DOI:10.1002/prac.19803220505

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

1H‐N.M.R. Spectroscopic Investigations on Innermolecular Mobility of Substituted 1,3‐DiazabutadienesTwo isomerization processes in substituted 1,3‐diazabutadienes can be observed by the method of dynamic n.m.r. spectroscopy. From coalescence phenomena the free activation enthalpies ΔG± are determined and discussed with regard to substituent effects and solvent dep

ISSN:0021-8383    

DOI:10.1002/prac.19803220506

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

31P‐NMR Investigation of N‐Aryl‐substituted Iminotriphenylphosphoranes: Hammett Relationship between31P Chemical Shift and Substituent ConstantsThe31P chemical shifts of p‐ and m‐substituted N‐arylimino‐triphenylphosphoranes reflect the electronic influence of the substituents and can be correlated by a Hammett relationship. This new correlation was used for the estimation of σ‐ resp. σ‐values for p‐(CH3)2N‐, p‐C6H5CO‐ and p‐C6H5N  N‐groups as well as for β‐naphthyl‐ and pyridyl(4)‐rings. The applicability of a similar Hammett equation for t

ISSN:0021-8383    

DOI:10.1002/prac.19803220507

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

Investigations to the Interaction between p‐Substituted Benzaldehydes and N.M.R.‐Shift ReagencesThe influence of n.m.r. shift reagents (Eu(fod)3and Pr(fod)3) on the chemical shifts of p‐dimethylaminobenzaldehyde has been investigated at13C and1H‐n.m.r. spectroscopy. The induced shifts of the protons are quantitatively explained on the basis of pseudocontact interaction. In13C‐n.m.r. spectra significant contact interactions have also been noted. The13C induced shifts have been separated into pseudocontact and contact contributions by two different methods. Calculations of relative equilibrium constants in mixtures have been carried out for p‐dimethylaminobenzaldehyde, p‐nitrobenzaldehyde, anisaldehyde and benzaldehyde. The relative equilibrium constants show a good correlation with the Hammett substitu

ISSN:0021-8383    

DOI:10.1002/prac.19803220508

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

Reactions of Difluoridichloromethane with HydrocarbonsThe reaction of difluordichloromethane with different hydrocarbons between 150°C and 250°C yields the CFCl2‐substituted hydrocarbons. Beside it the corresponding chlorides are formed. For the hydrocarbons studied the following sequence of reactivity against difluordichloro‐methane was found. n‐paraffins

ISSN:0021-8383    

DOI:10.1002/prac.19803220509

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

Computerized Analysis of Chemical Reaction Equations with Correction of StoichiometryA computer programme (SYNKL, synthonclassifier) was developed, which recognizes and separates synthon equations from reaction equations. The algorithm of the programme is based on an extensive silimarity proof and overlay of the most similar partial structures to encircel the synthon substructures. The programme is able to discern synthon substructures from nonstoichiometric appendants and to correct the stoichiometric differences in many cases.

ISSN:0021-8383    

DOI:10.1002/prac.19803220510

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

Reactions of 3‐Aroylimino‐3H‐1,2‐dithiolesThe thiolates3and10prepared from 3‐aroylimino‐4‐aroylthio‐5‐cyano‐3H‐1,2‐dithioles1with bases, react with alkylhalides and acylhalides to the corresponding 4‐S‐substituted compounds6, 11and7, respectively. Treatment of the thiolates with 1‐chloropropanone gives the bicyclic compound12by intramolecular cyclization involving the 5‐cyano‐group. 3,6‐Bis‐(acylimino)‐3H,6H‐[4,3‐c] [1,2]‐dithioles2or8are prepared from the S‐acylated dithioles1or7and sulphur in pyridine/benzene. 1,2,4‐Triazines13are formed by the reaction of dithiol es1orthiolates3with phenylhydrazine. The thiolates give upon protonation the mesoionic dithioliumthiolates4. Coordination compounds are obtained from the reaction of the thiolates with cations of 3d‐elements. On the basis of the chemical behaviour of the new 3‐acylimino‐1,2‐dithioles and the results of spectroscopic measurements a strong bonding interaction between the N‐acyl‐carbonylgrou

ISSN:0021-8383    

DOI:10.1002/prac.19803220511

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY