a-Metallierte Isocyanide 1 reagieren rnit Schiff-Basen 5 uber die Zwischenstufen 6 und 7 zu 2-unsubstituierten 2-Imidazolinen 8. Die 2-metallierten Imidazoline vom Typ 7 kBnnen rnit Elektrophilen zu 2-substituierten 2-Imidazolinen (z. B. 9) umgesetzt werden. -2-Imidazolin-4-carbonsBureester 8fo erhalt man alternativ aus 2-IsocyanacrylsPureestern 11 a, b und primBren Aminen oder Ammoniak. -Die 2-Imidazoline 8 liefern bei der Hydrolyse 1,2-Diamine 13 oder 2,3-Diaminoalkansluren 14. S y n t h~ with a-Metalnted Isocyanides, xxxM1) -2-Imidazoliies from c+MetaIated Isocyanides and Schiff Bases; 1,2-D-s and l,%DiaminoaIkaooic acids a-Metalated isocyanides 1 react with Schiff bases 5 to give via the intermediates 6 and 7 2-unsubstituted 2-imidazolines 8. The intermediate 2-metalated 2-imidazolines 7 can be trapped with electrophiles to give 2-substituted 2-imidazolines (for instance 9). -Alkyl 2-imidazoline-4-carboxylates 8fo can be obtained alternatively from alkyl 2-isocyanoacrylates 11 a, b and primary amines or ammonia. -On acides hydrolysis 2-imidazolines 8 give 1,2-diamines 13 or 2.3-diaminoalkanoic acids 14.Die praparative Bedeutung der in unserem Arbeitskreis aufgefundenen a-metallierten Isocyanide 1 2 ) beruht unter anderem darauf, daR sie im metallierten, d. h. anionisierten Kohlenstoffatom ein nucleophiles Zentrum enthalten, das sie zur Addition (Schritt a) an polare Mehrfachbindungen (Typ 2) befahigt und im ,,zweibindigenc' Isocyanidkohlenstoffatom ein elektrophiles Zentrum besitzea, das Heterocyclisierung der Addukte 3 (Schritt b) zu den Heterocyclen 4 ermoglicht3.4).

Monolayers of bifunctional bolaamphiphiles were self-assembled on a polymeric substrate (spin-coated film of poly(allylamine hydrochloride)). Various features of the novel bifunctional, well-ordered, and relatively stiff monolayer and the subsequent reactions of the exposed benzoyl azide groups were investigated. The characterization of the monolayers and the kinetics of self-assembly was determined via reflection−absorption infrared spectroscopy and ellipsometry. Atomic force microscopy and ellipsometry were used to measure roughness and thickness, respectively. From molecular modeling and ellipsometry, the bolaaphiphiles in the monolayers were found to be inclined at an angle of about 68° to the normal. In addition, the monomolecular layers appeared to be fairly crystalline. Serial functionalization of the exposed benzoyl azide groups with dansyl-cadaverine in the liquid phase followed by propylamine in the gas phase illustrated a stable, dense, well-ordered, two-dimensional monomolecular layer of bolaamphiphiles. Photopatterning, via UV irradiation of exposed benzoyl azide groups, was also demonstrated. The novelty of the surface modification procedure described here is the extraordinary ease with which self-assembly took place and the stability of the resulting monolayers which formed a highly reactive new surface suitable for further modification. Arranging molecules in a tidy ordered array on a polymeric surface is a main result of this work.

The present state of knowledge of the mechanism of the allyl nickel complex catalysed stereoselective butadiene polymerization is outlined. On the basis of the reaction model, which has been worked out more thoroughly and comprehensively by our systematic experimental investigations during the last years, the thermodynamic and kinetic control of the catalytic activity and selectivity in dependence on the structure of the allylnickel complexes will be discussed. Finally, it will be shown how the structure of the technical nickel catalyst could be elucidated for the first time and how its catalytic properties can be explained in the framework of the derived structure‐activity relationships.

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