摘要:

Electrochemical Synthesis of 1,1‐Dichloro‐4‐methylpenta‐1,3‐dieneReaction of 1,1,1‐trichloro‐4‐methylpent‐3‐en‐2‐ol (2) with inorganic acid halides yielded several polychloroalkenes (3–5). These compounds were utilized for the electrochemical synthesis of 1,1‐dichloro

ISSN:0021-8383    

DOI:10.1002/prac.19893310402

出版商:WILEY‐VCH Verlag GmbH    

年代:1989

数据来源: WILEY

ISSN:0021-8383    

DOI:10.1002/prac.19893310403

出版商:WILEY‐VCH Verlag GmbH    

年代:1989

数据来源: WILEY

摘要:

Furylvinylhalides. X. Reactions of β‐Fur‐2‐yl‐β‐chloro‐α‐cyanoacrylic Acid Derivatives with Hydrazinesβ‐Fur‐2‐yl‐β‐chloro‐α‐cyanoacrylic acid derivatives3react with hydrazines yielding 3‐fur‐2‐yl‐5‐aminopyrazoles5or 3‐fur‐2‐yl‐4‐cyanpyrazolin‐5‐ones6. In some cases the β‐h

ISSN:0021-8383    

DOI:10.1002/prac.19893310404

出版商:WILEY‐VCH Verlag GmbH    

年代:1989

数据来源: WILEY

摘要:

Structure Reactivity Correlations on Coordinatively Unsaturated Metal Chelate Complexes. XI. Effect of the Central Atom and the Ligands on the Mass Spectrometric Fragmentation of Chelate Complexes with Macrocyclic and Open Chain Schiff Base LigandsThe influence of the central atom on the mass spectrometric fragmentation of the compounds1–5is compared. Whereas the ligands (Mt = 2H) show a strong fragmentation with a farreaching cleavage, the metal complexes with exception of Cu‐4 and Cu‐5 show always the molecular ion signal as the base peak. The main fragmentions [M‐C2H5O]⊕, [M‐2(C2H5O)]2⊕, [M‐C2H4]⊕., and [M‐C2H4CO2]⊕.may be related to the ‘cyclidene’ structures6–7, the carboxylic acid8, and its decarboxylation product9. In the case of the copper chelates1–4the fragment [M‐C2H6O].⊕/2⊕with one or two positive charges is dominating over the peak [M‐C2H5O]⊕. This may be due to the abstraction of one H from an ethylene (type1,2,4) or a methyl (type3) group with concomitant reduction to

ISSN:0021-8383    

DOI:10.1002/prac.19893310405

出版商:WILEY‐VCH Verlag GmbH    

年代:1989

数据来源: WILEY

摘要:

Synthesis of S‐(1‐Benzoyl‐2‐bis‐methylthio)‐vinyl N,N‐Pentamethylene‐thiocarbamates and Their Reactions with N‐NucleophilesThe S‐(1‐benzoyl‐2‐bis‐methylthio)‐vinyl‐N,N‐pentamethylene‐thiocarbamates3a–dare synthesized by reaction of S‐phenacyl‐N,N‐pentamethylene‐thiocarbamates (1a–d) with carbon disulfide under phase‐transfer conditions. These compounds3a–dand the dithiocarbamates5a–dreact with N‐nucleophiles forming the ketene‐S,N‐acetals6–14, the S‐phenacyl α‐(imidazolidine‐2‐ylidene)‐N,N‐pentamethylene‐thio‐ or ‐dithiocarbamates15–22, S‐(substituted pyrazol‐4‐yl)‐23–28and S

ISSN:0021-8383    

DOI:10.1002/prac.19893310406

出版商:WILEY‐VCH Verlag GmbH    

年代:1989

数据来源: WILEY

摘要:

About the Reaction of „Pyrazolone Blue”︁ with DiazomethaneThe reaction of “pyrazolone blue” with diazomethane was investigated. A pyridazinone derivative3, a heterocyclic spiro‐cyclopropyl product4and a compound7, which contains three pyrazolone and two diazomethane entities, are formed.3reacts with an excess of diazomethane to the methoxy derivative6. The spiro‐cyclopropyl compound4is not stable and isomerizes to the corresponding 4,4′‐methylidene‐bispyrazolone5. The structures of the products were established by spectroscopic methods

ISSN:0021-8383    

DOI:10.1002/prac.19893310407

出版商:WILEY‐VCH Verlag GmbH    

年代:1989

数据来源: WILEY

摘要:

AbstractGlycol monoesters were produced by oxidation of acetals with oxygen, hydroperoxides, hydrogen peroxide, hydrotrioxide and ozon. Addition of salts of metals of variable valency and crown‐ether substantially increase the rate of oxidation and hydroxylation. The most efficient oxidizer is ozo

ISSN:0021-8383    

DOI:10.1002/prac.19893310408

出版商:WILEY‐VCH Verlag GmbH    

年代:1989

数据来源: WILEY

摘要:

Azoles. 22.1H‐ and13C‐N.M.R. Investigation of Isomeric‐3 and 5‐Amino‐Pyrazole DerivativesThe1H‐ and13C‐n.m.r. spectra of nine pairs of isomeric 3‐ and 5‐amino‐pyrazole derivatives1a—1iand2a—2iand some of their acetylderivatives have been assigned and discussed. It has been found that1H‐ and13C‐n.m.r. spectroscopy is a useful tool for differentation of the above menti

ISSN:0021-8383    

DOI:10.1002/prac.19893310409

出版商:WILEY‐VCH Verlag GmbH    

年代:1989

数据来源: WILEY

摘要:

AbstractThe oxidative decomposition of two structural isomers of dipropylene glycol, i.e. 2,4‐dimethyl‐3‐oxapentandiol‐1,5 (1) and 4‐oxaheptandiol‐2,6 (2) was studied. The maximum rate of oxidation of glycol1was ca. 20 times lower than that of glycol2. In the products of oxidation 15 different compounds were detected for the former glycol and 20 compounds for the latter. The products of decomposition were the mixtures of water and carboxy acid, acetal, alcohol, aldehyde, ketone, ester, unsaturated ether and hydroperoxy type of compounds of different structure. The mechanism of product formation i

ISSN:0021-8383    

DOI:10.1002/prac.19893310410

出版商:WILEY‐VCH Verlag GmbH    

年代:1989

数据来源: WILEY

摘要:

Abstract1‐(2′‐Hydroxy‐5′‐alkylphenyl)‐1‐ethanone oximes with a normal alkyl group containing 2 to 12 carbon atoms and 1‐(2′‐hydroxy‐5′‐methylphenyl)‐1‐alkanone oximes containing 1 to 11 carbon atoms in the hydrocarbon chain were synthesized. Spectral data (u.v., i.r., n.m.r. and13C) of oximes are reported. Four of these oximes were used for copper extraction from acidic solution. The results obtained indicate, that these oximes are better extractants than alkyl derivatives

ISSN:0021-8383    

DOI:10.1002/prac.19893310411

出版商:WILEY‐VCH Verlag GmbH    

年代:1989

数据来源: WILEY