ISSN:0021-8383    

DOI:10.1002/prac.19833250102

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

Exo‐ and Endohormones. V. Synthesen des Sexualpheromons des Kiefernknospentriebwicklers(Rhyacionia buoliana) durch Grignard‐ReaktionenGrignard‐Kopplungen zwischen zwei entsprechenden Synthonen führen zum (E)‐9‐Dodecen‐1‐ylacetat (1), dem Sexuallockstoff des Kiefernknospentriebwicklers (Rhyacionioa buoliana). Als solche Synthon‐Paare wurden 1‐Brom‐(E)‐2‐penten (2) und 7‐Bromheptyltetrahydropyranylether (3) bzw. (E)‐3‐Hexen‐1‐yltosylat (4) und 6‐Bromhexyltrimethylsilylether (5) eingesetzt. Das Endprodukt (1) und die wichtigsten Zwischenprodukte wurden durch ihre1H‐ und13C‐NMR‐Spektren charakterisiert. Durch die zweite Synthese wurden 100%

ISSN:0021-8383    

DOI:10.1002/prac.19833250103

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

Complexes of Iron with Aromatic LigandsThe reaction of FeCl3· 6 H2O with several substituted o‐phenylene diamines forms complexes of the Fe(II)‐ion with o‐quinone diimines. Before the formation of these complexes there are a few of redox reactions between Fe(III)ions and the diamines. The Fe(III)/o‐quinone diimine‐complex is an intermediate which was characterized by means of spectroscopic methods. The two forms of 6‐oxy‐7‐nitrosobenzthiazoline produce only one 1:3 complex with Fe(II)ions. Also the N‐methyl‐6‐oxy‐7‐nitrosobenzthiazolium iodide forms a 1:3 complex. In the former complex the quinone‐oxim‐form is the ligand. The isolated complexes were characterized through elemental

ISSN:0021-8383    

DOI:10.1002/prac.19833250104

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

Studies on the Hydrolysis of Aromatic SulfochloridesThe hydrolysis of aromatic sulfochlorides can bei described by a second‐order law. Due to the strength of the base the constants of velocity are between 10−6(H2O) or 103(OH−) 1 mol−1s−1respectively. The reaction of benzensulfochlorides proceeds according to an addition‐elimination mechanism, whereas benzylic sulfochlorides, reacting with a strong base, proceed to an elimination‐addit

ISSN:0021-8383    

DOI:10.1002/prac.19833250105

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

3‐Nitromethyl‐pyrazoles from 2‐Cyano‐3‐methylthio‐4‐nitrocrotonic Acid Derivatives2‐Cyano‐3‐methylthio‐4‐nitrocrotonic Acid Derivatives1a,breact with hydrazines to form the 5‐amino‐3‐nitromethyl‐pyrazoles2a–cand the 5‐nitromethyl‐pyrazol‐3‐one3respectively. Contrary to this carboxylic hydrazides attacks the nitro group. For the resulting products the structure of pyrrol‐2,5‐dione oximes4is proposed. On the similar way from 3‐methylthio‐4‐nitro‐2‐phenylcrotononitrile1cand phenylhydrazine the pyrrol‐2,5‐dione hydrazone5arises. Subsequent reactions of2yield 3‐nitromethyl‐pyrazole derivatives6, 3

ISSN:0021-8383    

DOI:10.1002/prac.19833250106

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

Aminolyse von Urethanen. II. Kinetik und Mechanismus der Aminolyse des Benzyl N‐phenylurethans mit Monoethanolamin in aprotischen LösungsmittelnDie Kinetik der Aminolyse des Benzyl‐N‐phenylurethans in Gegenwart eines Überschusses an Monoethanolamin wurde zwischen 140–160°C in zwei aprotischen Lösungsmitteln (Amin und Ether) verfolgt.Es werden komplexe Geschwindigkeitsgesetze der Form kexp.= k Amin + k' Amin2gefunden und mit einem E1cB‐Verlauf der Aminolysereaktion interpretiert. Ein synchroner E‐A‐Mechanismus unter Zwischenbildung eines Isocyanats wird dadurch ausgeschlossen, da die N‐methylierte Verbin

ISSN:0021-8383    

DOI:10.1002/prac.19833250107

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

Vinylogous Acyl Compounds. XX. Reactivity and Toxicity of Aryl‐substituted β‐Chlorovinyl Ketones, β‐Chlorovinyl Aldehydes, and β‐Chlorovinyl Methyleniminium SaltsBased on kinetic measurements, the nucleophilic replaceability of the chlorine in aromatic β‐chlorovinyl ketones ArCO‐CH  CH‐Cl (1), isomeric β‐chlorovinyl aldehydes OCHCHC(Cl)Ar(2), and corresponding β‐chlorovinyl methyleniminium salts Me2N⊕;CHCHC(Cl)Ar X⊖(3) is compared and related to toxicological findings. The chemical reactivity of these important synthetic building blocks increases in the order2<1<3, the acute toxicity (24 h LD50i. p. in the mouse) shows the graduation2<3<1. Compounds of type1prove to be relatively toxic (LD5024–42 mg/kg) and display a marked necrotic action after percutaneous absorption, whereas the aldehydes2have not only a minor acute toxicity (LD50158–298 mg/kg) but also a somewhat less marked skin damaging activity. In addition, the LD50values of selected β‐chlorovinyl carbonyl compounds are compared with those of corresponding halogen‐free compounds as well as of vinylogous carbonamidium salts ArCOCHCHN⊕R3X⊖. The latter, which can be used as synthetic equivalents of1, differ in both the r

ISSN:0021-8383    

DOI:10.1002/prac.19833250108

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

Kinetic Investigations of the Pyrolysis of Mono‐n‐alkyl‐cyclohexanesThe thermal decomposition of cyclohexane and six mono‐n‐alkylcyclohexanes was studied kinetically in a metallic laboratory tubular reactor at 650 to 850°C and atmospheric pressure.Kinetic parameters were found to be a function of length of the alkylic side chain. A comparison with analogous parameters of n‐paraffins and the unsubstituted cyclohexane allowed the conclusion that CC‐scission in the alkylic chain is the initial reaction in pyrolysis of n‐alkylcyclohexanes followed by radical attacks to all CH‐bonds

ISSN:0021-8383    

DOI:10.1002/prac.19833250109

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

Graphical and Numerical Analysis of Temperature Dependent Fluorescence Quantum YieldsThe graphical and numerical analysis of temperature dependent fluorescence quantum yields is a suitable method to derive the number and the temperature behaviour of various radiationless processes which are involved in the deactivation of a fluorescent excited state.In this paper eight fluorophore/solvent‐systems were analysed, (T from 77K to 320 K) both, numerically and graphically. A computer program (SLAMS) was developed. It bases on a nonlinear regression and produces deactivation parameters and statements concerning the statistics of data, too. The possibilities, preferences and limits of the numerical analysis are discussed in comparison with the graphical method. The calculated results are discussed with regard to the number of radiationless processes, the accuracy of the quantum yield determination and the investigated temperature range.For the physical interpretation of the kinetic parameters of deactivation in addition to the authors results values from the literature were use

ISSN:0021-8383    

DOI:10.1002/prac.19833250110

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

The Nitrile Carboxamide Rearrangement and the Formation of Heterocycles via Cyano‐cyclohexenyl‐ureaAnthranilic amide and cyanogen bromide form Cyano‐phenyl‐urea (7) via Nitrile Carboxamide Rearrangement. Cyclisation of cyano‐cyclohexenyl‐urea (4) yields 4‐amino‐2,3,5,6,7,8‐hexahydroquinazolin‐2‐one (10).4and amines form N‐cyano‐cyclohexenyl‐N'‐alkyl‐ureas (11a–e) or 3‐alkyl‐4‐amino‐hexahydroquinazolin‐2‐ones (12a–g).4and α‐aminoacids yield octahydro‐imidazolo‐quinazolindiones (14a–b). Oxo‐cyclohexane‐2‐carboxamide (1) and

ISSN:0021-8383    

DOI:10.1002/prac.19833250111

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY