摘要:

AbstractThe present status of research on condensed vanadic, molybdic, and tungstic acids is reviewed. Information about the structure and formation of polyanions can be obtained by X‐ray analysis and from nuclear magnetic resonance, infrared, and Raman spectra, as well as from complex formation in aqueous solution. Salts of the polyacids can be prepared in organic solvents by hydrolysis of esters of the metal oxoacid

ISSN:0570-0833    

DOI:10.1002/anie.196606891

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

摘要:

AbstractDi‐ and triaryl‐Δ2‐pyrazolines and their derivatives can be used as optical brighteners for synthetic fibers and plastics. The heterocycles are readily obtainable by several methods, e.g. condensation of β‐halogeno‐ or β‐dialkylaminopropiophenones with phenylhydrazine. A number of relationships can be detected between substitution and opti

ISSN:0570-0833    

DOI:10.1002/anie.196606991

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

摘要:

AbstractThe reaction of 1,3‐disubstituted ureas and 1‐arylsulfonyl‐3‐alkylureas with phosgene permits the preparation of a number of isocyanates and sulfonyl isocyanates that had not previously been described, or that were difficult to prepare. 1,3‐Disubstituted thioureas and 1‐aryl‐(or alkyl)sulfonyl‐3‐alkylthioureas give carbodiimides. Thionyl chloride and phosphorus pentachloride react with the urea derivatives in the same way as phosgene. Oxalyl chloride reacts with ureas to form parabanic acid derivatives, whereas with thiourea it gives 2‐imino‐1,3‐thiazolidine‐4,5‐diones, which can isomerize to

ISSN:0570-0833    

DOI:10.1002/anie.196607041

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

摘要:

AbstractThe range of stability of transition metal oxocations in aqueous solution is discussed. Species with a metal‐oxygen bond of order higher than unity are particularly interesting. Bond orders can sometimes be determined from bond lengths and angles, but generally only by infrared spectroscopy. – The frequency range of the metal‐oxygen stretching vibration, previously assumed as about 900–1100 cm−1, must according to these investigations be extended at least to 780 cm−1if all multiple bonds, particularly those in trans‐dioxo complexes, are to be included. Broad bands down to 650 cm−1are ascribed to metal‐oxygen bridges. — The existence of cations such as ZrO2+and VO 2+, or of the “well‐known” titanyl ion, TiO2+, has never been proved. In many cases polynuclear, oxygen‐bridged oxo

ISSN:0570-0833    

DOI:10.1002/anie.196607121

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196607221

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196607232

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196607242

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196607252

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196607262

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196607272

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY