Fragmentation Sous Impact Electronique de la Pyrrolidine et D'Isoindolines N-Nitrosees et N-Aminees

Mass spectral fragmentations of N-nitroso and N-amino derivatives of pyrrolidine, isoindoline and diphenyl isoindoline have been studied. Medium resolution and site specific deuterium labelling lead us to suggest fragmentation pathways.     

Kleine Gehalte an Mangan in Legierungen von Magnesium mit den Seltenen

Ohne Zusammenfassung     

Sulfur modification of polyethylene surfaces. II. Modification of polyethylene surfaces with fuming sulfuric acid

Previous work has shown that atomic sulfur irreversibility modifies polyethylene, presumably through an insertion reaction into carbon—hydrogen bonds with formation of surface thiol groups. The thiol groups were then oxidized to sulfonic acid surface groups, which were further reacted chemically as shown by wettability measurements. In this work the thiol group was bypassed and the surface sulfonic acid groups were obtained by exposing the polyethylene surface directly to fuming sulfuric acid. The sulfonic acid groups were reacted further. Critical surface tension values identical with those in the previous work with atomic sulfur were obtained, thus substantiating the previous work.     

Catalyseurs d′acylation supportes: Synthese et activite d′amino-4 pyridines fixees sur polymeres

New polystyrene-supported 4-amino pyridines are described. Some of them exhibit a good catalytic activity in acylation reactions.     

Etude par Résonance Magnétique Nucléaire de dioxaphosphorinanes-1,3,2 à liaison P?N extracyclique. Exemple de changement d'orientation de la liaison P?N

The ¹H NMR spectra of several 1,3,2-dioxaphosphorinanes bearing an extracyclic P? N bond have been analysed. The ³J(POCH) couplings are strongly dependent upon the orientation of the bond around the phosphorus atom. Depending upon the nature of the bonds attached to the nitrogen atom, the dioxaphosphorinane ring may adopt either a fixed chair conformation with the P? N bond in the axial or equatorial orientation, or it may be in equilibrium between two chair conformations where the P? N bond is alternately axial or equatorial. The equilibrium is fast on the NMR time scale.