Dünnschicht-Chromatographie der Methylolmelamine

Identification of the components in a methylolmelamine mixture by thin-layer chromatography was facilitated after obtaining each of the individual methylolmelamines (mono-, di-, tri-, tetra-, penta- and hexamethylolmelamine). By the use of two-dimensional thin-layer chromatography it was noted that no change in the composition of the mixture takes place during the time of Chromatographic development. Separation was achieved on cellulose layers using butanol/ethanol/water (4∶1∶2) as solvent and ammonia-alkaline AgNO₃ solution as detection reagent.     

On a proposed phenomenological determination of the strength of the dissipative forces in heavy ion reactions

We investigate a mechanism which shows that the experimental determination of the direction of the final spins of the nuclei in deep inelastic collisions yields distinct information on the strength of the radial dissipative forces since, in certain systems, the classical trajectories are accordingly scattered to positive or to negative deflection angles. The radial friction constant marking off both regions from each other amounts to c_r ≈ 2 × 10^?21 MeV fm sec for Ar + Th at E_lab^inc = 388 MeV and to c_r ≈ 1 × 10^?21 MeV fm sec for O + Pb at E_lab^inc = 315 MeV.     

Über die Struktur vernetzter Polymerisate aus Styrol,p-Jodstyrol und Divinylbenzol

Colloid and Polymer Science - Aus dem Copolymerisationsverhalten von Styrol und Divinylbenzol läßt sich ableiten, daß derartige Copolymere mit geringen Divinylbenzolgehalten eine...     

Über die Darstellung einiger p-substituierter Styrolderivate

Zusammenfassung Es wird die Darstellung von p-Isopropylstyrol und p-(-Bromäthyl)-styrol aus den entsprechenden Methylaryl-carbinolen beschrieben. Ausgehend von p-(-Bromäthyl)-styrol sind p-Äthinylstyrol und p-Divinylbenzol zugänglich. Ferner wird über einige Untersuchungen zur Dehydratisierung von Methylaryl-carbinolen berichtet, wobei verschiedene, z. T. bisher unbekannte Di--aryl-äthyl-äther isoliert wurden.Mit 2 AbbildungenTeil der DissertationH.-G. Keppler, Darmstadt 1962.     

Nachbargruppenbeteiligung bei der elektronen-stoßinduzierten Fragmentierung von elektronenarmen 2,2′-Biphenolbenzoaten

Electron deficient 2,2′-biphenyl benzoates decompose under electron impact conditions by loss of benzoic anhydride. Both stepwise and pericyclic mechanisms are observed as confirmed by the ‘direct analysis of daughter ions’ (DADI) technique.     

Tetrazoles from N-(4-dimethylaminophenyl)nitrones and hydrogen azide

The reaction of N-(4-dimethylaminophenyl)nitrones, 1 , with hydrogen azide proceeds via three distinct pathways to give a mixture of two tetrazoles, 5 and 9 , and a 2-azido-4-dimethyl-aminoaniline derivative, 6 . The proportions largely depend on the electron-withdrawing force resident in the function R attached to nitrone carbon. The formation of 5 constitutes a new synthetic approach to 1,5-disubstituted tetrazoles.