Struktur, Stereoelektronik und Synthesepotenzial von 1,2‐Bisonio‐1,2‐bis(dialkylamino)ethenen

Abstract

Mithilfe der selbstaktivierenden silylassistierten Polyoniosubstitution (SASAPOS) konnten erste Vertreter von 1,2‐Bisonio‐1,2‐bis(dialkylamino)ethenen synthetisiert und strukturell charakterisiert werden (siehe Bild; DMAP=4‐Dimethylaminopyridin). Dabei wurden – je nach Art der eingeführten Onioliganden – zwei grundlegende Strukturtypen gefunden, die sich hinsichtlich ihrer internen stereoelektronischen Stabilisierung unterscheiden.

4,5‐Bis(dialkylamino)‐Substituted Imidazolium Systems: Facile Access to N‐Heterocyclic Carbenes with Self‐Umpolung Option

“…The decisive building block for the synthesis of 9 turned out to be the bis(phosphonio)diaminoethene 8, which preparation we recently reported. [13] As an a 1 ,a 2 -biselectrophile that is easy to handle and dose, ethene 8 can be conveniently converted to the desired imidazolium system 9 by a novel [3+2] cyclodisubstitution reaction with formamidine anions as d 0 ,d 2 -bisnucleophiles (Scheme 3). The dicationic salt 8 serves as a reagent for the ethene-bis(dimethyliminium) synthon 10 and thus indirectly also for the elusive C 2 O 2 [14] (11).…”

From DMF to isatine: A novel and general one‐pot synthesis of isatine and its N‐unsubstituted derivatives vianucleophilic substitution reactions on 1,2‐bis(dimethylamino)‐1,2‐dichloro‐ethene

“…In the course of our investigations of nucleophilic substitution reactions on 1,2‐bis(dimethylamino)‐1,2‐bisonio‐ethenes [11], we have developed a new versatile one‐pot synthesis of N‐unsubstituted isatine derivatives, starting from the common solvent DMF and involving mostly customary chemicals, as described in more detail below.…”